To understand the Diesel principle let us begin by remembering that to the compression of a charge in a gas engine there is a moderate limit; if this be exceeded the heat of compression prematurely ignites the gases, so as to prevent due action. The air in a bicycle tire is compressed but moderately, and yet every man who has worked a bicycle air-pump with energy knows that soon its cylinder grows warm to the touch. On this very principle, that mechanical work is convertible into heat, our grandfathers had an ingenious mode of producing fire. In a syringe with a glass barrel they placed a piston fitting snugly. In a cavity of this piston they fastened a bit of cotton wool soaked in bisulphide of carbon. On forcing the piston suddenly into the cylinder, the air, quickly compressed, became hot enough to set the cotton wool on fire. The heat evolved in the compression of air is turned to account in the Diesel oil engine so as to make it the most economical converter of heat into work ever devised. First the mechanism compresses air alone to 500 pounds per square inch, then and then only the oil for combustion is injected, to take fire instantly from the heat of the compressed air. A governor regulates the period of burning; this is usually during one tenth part of the stroke, the expansion of the burned products completing the stroke. Because 500 pounds is a pressure out of the question for the compression of the mixed charge of air and combustible gas in an ordinary gas cylinder, the Diesel engine excels in economy any gas engine thus far built. At Ghent in 1903 a Diesel engine developed 165 brake horse-power from crude Texas oil with the extraordinary net efficiency of 32.3 per cent. At the St. Louis Exposition, 1904, three Diesel engines, using oil costing three cents per gallon, delivered for seven months, during eleven hours each day, at half-load, an average of 250 kilowatts at an expense for fuel of but three tenths of one cent per kilowatt hour on the switchboard, including all generator and line losses. Engineers of the first rank are convinced that the Diesel principle may be successfully embodied in gas engines. That done, with a success approaching the effectiveness of Diesel’s oil motor, we may expect steam engines and turbines to be largely dismissed from service.

Gasoline Engines.

Gasoline, although higher in price than petroleum, is commonly used in automobiles and launches. It can be atomized more quickly and fully, and without heat. To equalize motion, minimize jars, and reduce the weight of its fly-wheel, an automobile of high power has usually four cylinders with cranks set at an angle of 90 degrees with each other. The inlet valve is operated positively and, as a rule, is interchangeable with the exhaust valve. The ignition spark is furnished by a motor-driven magneto, or by a battery operating an induction coil; the lubricant is distributed by a sight-feed system, hand regulated. Cooling is effected by water circulated by a pump through jackets surrounding all cylinders and valves, each jacket having a surface of the utmost extent upon which a swiftly rotated fan drives a stream of air.

Alcohol Engines.

For some years France and Germany have used alcohol as a fuel in engines, no excise tax being imposed on alcohol employed for industrial purposes. On January 1, 1907, this will also be the case in the United States, so that we may expect alcohol to take a leading place as fuel in motors. “It has,” says Professor Elihu Thomson, “gallon for gallon less heating power than gasoline, but equal efficiency in an internal combustion engine, because it throws away less heat in waste gases and in the water jacket. A mixture of alcohol vapor with air stands a much higher compression than does a mixture of gasoline and air without premature explosion. . . . There is now beginning an application of the internal combustion engine for railroad cars on short lines which are feeders to main lines. The growth of this business may be hampered in the near future by the cost of gasoline. In this case alcohol, producible in unlimited amount, could be substituted.”

An important advantage in using alcohol is its comparative safety. In case of fire oils and gasolines float on the water intended to quench a blaze; alcohol blends with that water and the flame is subdued.

Whether oil, gasoline or alcohol be their fuel, internal combustion motors gain steadily in public acceptance. On the farm they are gradually displacing the horse. An engine, which costs nothing when it is idle, shells corn, saws wood, cuts fodder, grinds feed, separates and churns cream, drives a thrasher, turns a mill, lifts water, and performs a hundred other chores quickly, simply and cheaply.

Steam and Gas Motors United.

Mr. Henry G. Stott, chief engineer of the Interborough Rapid Transit Company, New York, has recently discussed power plant economies in so thorough and suggestive a manner as to elicit the interest of engineers the world over.[42] Basing his remarks on the records of the huge plant of his Company at 74th Street and the East River, New York, he presents this table of the average losses in converting the heat from one pound of coal into electricity:—

Carbon dioxide (CO²) is absorbed by a solution of caustic potash. The Ados recorder based upon this absorption has enabled Mr. Stott to learn the proportion of carbon dioxide in the gases passing to the stack, the higher that proportion, the more thorough the combustion. He finds first as an element of economy careful firing, so as to avoid “holes” or thin places in a fire, through which air wastefully pours, chilling the furnace. Next in importance is adapting draft to fuel: small anthracite requires a draft of 1.5 inches of water; with a draft of but .2 inch of water one pound of dry bituminous coal has evaporated 10.6 pounds of water, with a draft of 1 inch this fell to 8.7 pounds. Mr. Stott estimates that scientific methods of firing can reduce losses to the stack to 12.7 per cent., and possibly to 10 per cent.

Respecting the loss of 8 per cent. in boiler radiation and leakage, he maintains that this is largely due to the inefficient setting of brick which, besides permitting radiation, admits much air by infiltration. The remedy is to employ the best methods of boiler setting, such as an iron-plate air-tight case enclosing a carbonate of magnesia lining outside the brickwork.

Regarding the main loss, that of 60.1 per cent. to the condenser, Mr. Stott points out that superheating could reduce this by 6 per cent. He observes that in the higher pressures of a steam cycle a reciprocating engine has an advantage, while in the lower pressures a steam turbine is more efficient. Combine them, he remarks, and use each where it is the more profitable. But in his view for the utmost economy a new type of plant should unite both steam and gas driven units.

“Over a year ago,” he says, “while watching the effect of putting a large steam turbine having a sensitive governor in connection with reciprocating engine-driven units having sluggish governors, it occurred to me that here was the solution of the gas engine problem; for the turbine immediately proceeded to act like an ideal storage battery; that is, a storage battery whose potential will not fall at the moment of taking up load, for all the load fluctuations of the plant were taken up by the steam turbine, and the reciprocating engines went on carrying almost constant loads, whilst the turbine load fluctuated between nothing and 8,000 kilowatts in periods of less than ten seconds.

“The combination of gas engines and steam turbines in a single plant promises improved efficiency whilst removing the objection to the gas engine, namely, its inability to carry heavy overloads. A steam turbine can easily be designed to take care of 100 per cent. overload for a few seconds; and as the load fluctuation in any plant will probably not average more than 25 per cent. with a maximum of 50 per cent. for a few seconds, it would seem that if a plant were designed to operate normally with one half its capacity in gas engines and one half in steam turbines, any fluctuations of load likely to arise in practice could be taken care of.”

Discussing in detail the performance of such a plant, Mr. Stott concludes that its average total thermal efficiency would be 24.5 per cent., as against 10.3 per cent. in the plant whose record he had presented.

Heating and Power Production United.

In the bill of particulars drawn up by Mr. Stott it was shown that no less than 60.1 per cent. of the total heat from his fuel had gone into the condenser where, joined to the stream of the East River, it had been wasted. Had he used non-condensing motors the loss in exhausts would have been larger, and yet when a non-condensing motor is joined to a heating plant the whole investment may be much more profitable than where condensing motors throw away all the heat of their exhausts. Long ago some pioneer of unrecorded name, using a non-condensing steam engine, warmed his factory or mill with its exhaust steam. In summer that steam sped idly into the air, in winter it saved him so much coal that his motive power cost him almost nothing. By thus uniting the production of power and heat he showed, as few men have shown, how a great waste may be exchanged for a large profit. In the Northern States and in Canada the main use for fuel is for heating not only dwellings, but the furnaces that pour out iron and steel, the ovens that bake pottery, tiles, and so on. When but moderate temperatures are desired, as in warming a house, exhaust steam serves admirably, and so might the exhausts from gas engines. Indeed we here strike the key-note of modern fuel economy which is that wherever possible fuel should first deliver all the motive power that can be squeezed out of it, when and only when the remainder of its heat, much the larger part of the whole, should be used for warming.[43] This plan, already adopted in a good many cases, can be vastly extended with profit. In blast furnaces the first task of the fuel is performed at an extreme temperature; that work completed the gases of combustion may be purified and sent into gas engines to produce motive power at little cost.

Heating and Ventilating by Fans.

A word was said on page 380 regarding the method now growing in favor for heating machine-shops by sending warmed air where it is needed, and not allowing it to go where it would proceed of itself and be wasted. Two illustrations show a Sturtevant ventilating fan-wheel, without its casing, and a Monogram exhauster and solid base heater, as used in many modern installations. The net gain in sending warmed air just where it does most good is comparable with the profit in mechanical draft for a furnace as compared with natural draft. Either live or exhaust steam may be used in the heating coils through which the air is forced by the fan. See also illustration on page 380.

Steam plants which furnish both heat and electricity are being rapidly multiplied throughout America. In many cases these plants supply a single large hotel, or office building. The installation at the Mutual Life Building, New York, is of 2400 horse-power, vying in dimensions with many a central plant. In Fostoria and Springfield, Ohio, in Milwaukee, Atlanta and other large cities, a central station provides heat and light and motive power to a considerable district.

District Steam Heating.

At Lockport, New York, a city of about 20,000 population, more than 350 dwellings and business premises are heated by the American District Steam Company, a concern which has installed more than 250 similar plants throughout the Union. The advantages of this system are plain:—cleanliness is promoted; customers handle no coal or ashes, tend no fires or boilers; the heat is more steadily and equably supplied than if it came from individual boilers; heat is ready day or night during the heating season; the hazard from fire is lowered and the risk of boiler explosion is abolished; water may be heated for laundries, bath-rooms and kitchens. Cheap fuel may be used, and stoked by machinery. An individual boiler in a building has to be large enough for its heaviest duty; in many cases it is called upon for but one tenth to one fifth of its full power, with much incidental waste. At a central station only as many boilers of a group are employed at a time as may be worked to their full capacity, responding to the demands of the weather.

At Lockport the steam-pipes are of wrought iron covered with sheet asbestos and enclosed in a round tin-lined wood casing, having a shell 4 inches thick, with a dead air space of about one inch between the tin and the asbestos. In its largest size this pipe has shown a total loss by radiation and conduction of but one part in four hundred in one mile; for the same distance the smallest pipe has suffered a loss of six per cent. Live steam is used at Lockport, but as a rule heating plants are supplied with exhaust steam. When intensely cold weather prevails this may be supplemented by boilers in reserve which supply live steam.

It is worth while to remark the tendency to unify, on lines of the best economy, a service of both heat and electricity. In Atlanta there were recently in operation twenty-two isolated electric plants. The central station installed a steam heating system, and as a result in less than a year all but two of the isolated plants went out of business.

Isolated Plants.

The success of the central station at Atlanta is due to the moderate scale of its charges. In the past there has been some complaint of the rates levied by central stations. In the future this complaint is likely to diminish, because an isolated plant for the production of heat and electricity was never before so low in cost, so efficient in working, as to-day. Well managed central stations broaden their market by putting a premium upon the utmost possible use of electricity. In Brooklyn, for example, the Edison Electric Company charges 10 cents per horse-power hour to customers using 100 to 250 horse-power hours per month; as consumption increases so do discounts until the customer who buys 5,000 horse-power hours pays 4 cents. The demand for current in all its diverse applications is stimulated with energy and address. A house or apartment of seven rooms is wired for twelve lights, with all fixtures complete, for $95. Signs for advertising purposes are provided gratis, on condition that they be lighted by the Company. The economy of a small ice machine or a refrigerator is pointed out all summer long, while in winter the comfort and convenience of electric heat is as plainly kept before the public. Such a policy as this takes account of the irrepressible facts of present day competition. When gas was the sole illuminant, producible only on a vast scale, served by an elaborate scheme of piping that from the nature of the case fell into a single hand, there was a liability to extortion. To-day in towns and cities electricity, the chief source of light, can be ground out anywhere simply, cheaply and without offence, incidentally affording when desired almost as much heat as if the fuel had been burnt to produce nothing else. Among the gifts bestowed by the electrician not the least is this conferring at the lowest price two prime necessities of life. But however liberal the management of a central station, many a fat plum will remain outside its pudding. A huge hotel, an office-building, factory, or department store, is best served by a plant of its own designed to furnish both heat and electricity, in which case the electric current will cost much less than if bought from a central station.

On occasion an isolated plant supplies a neighborhood, and at prices lower than those of a large central station which may be at a considerable distance. At Newark in the New Jersey Freie Zeitung building a 400 kilowatt plant is installed which supplies the neighbors in two blocks with electricity at 6 to 8 cents per kilowatt hour, according to the extent of their consumption. A necessary conduit crosses Campbell Street in this service. It seems likely that small power-centres of this kind, requiring no franchise, may be common in the near future, especially if united with heating systems. An inviting field for such installations is in the new residential quarters of our cities and towns, where in many cases a whole block might be cheaply and effectively served from a single plant.

Gas for Heat, Light and Power.

Heat, light and motive power may be provided either by steam or by gas. Modern industry does not tie itself to any particular servant, but chooses in turn whichever, under the circumstances of a case, will serve it well at least cost. Where natural gas is to be had at a low price it holds the field. But the area thus favored is small, so that producer gas is employed on a much larger scale. We have already seen (page 461) how coal may be gasified, valuable by-products seized, and a cheap gas be piped for miles with no liability to the condensation which befalls steam, while available for heating and for motive power. When this gas burns at a fairly high temperature, as does Dowson gas, it gives with thorium mantles a good light, so as to be an all round rival of electricity. Producer gas is preferable to solid coal because perfectly clean; it banishes the smoke nuisance, and is regulated by a touch. Mr. F. W. Harbord in his work on Steel (see page 177), says:—

“The ease with which perfect combustion of a gas can be obtained by regulating the supply of gas and air, the readiness with which it can be conducted to any required point, superheated or burned under pressure, made to give an oxidizing or a reducing flame at pleasure, and the general control that can be exercised over the size and temperature of the flame, in most cases more than compensate for the reduction in heat units due to gasification. . . . The necessity for superheating the fuel, and for keeping solid fuel out of contact with the bath of metal, make gaseous fuel indispensable in the open hearth furnace, and until Siemens solved the problem of cheap gasification of coal, this process of steel-making was impossible.”

Gaseous fuels are employed not only in steel making but in the manufacture of glass, pottery, chemicals, and much else.

When gas is used in gas engines to produce motive power, the exhausts having high temperatures may be profitably applied to heating water, or raising steam, for warming purposes.

Whether central stations employ steam or gas, or unite both, it is certain that a unification of the service of heat, light, and motive power including that required for traction, would in all our towns and cities be attended by great economy, by the abolition of much discomfort and unnecessary drudgery. A large city, such as New York or Chicago, could be supplied with these three cardinal necessities from comparatively few centres.

Electric Traction.

Such centres may, before many years elapse, be found stretching out into the distant suburbs of cities, and linking town to town. This chiefly because electricity has become a formidable rival to steam in interurban locomotion. By the time this page is printed, the New York Central & Hudson River Railroad will have begun operating its suburban trains from New York by electricity. For this service locomotives built by the General Electric Company, Schenectady, New York, will be in commission. Each will develop 2,200 to 3,000 horse-power. In careful tests a locomotive of this kind reached a speed of fifty miles an hour in 127 seconds, whereas a “Pacific” steam locomotive required 203 seconds; an important difference, especially where stops are frequent. Each locomotive, with its train of cars, weighed 513 tons. The steam locomotive with its tender weighed 171 tons; its electric rival weighed but 100 tons. So much for the gain in leaving both furnace and boiler at home, while their power is received through a special rail at rest.

CHAPTER XXXII
A FEW SOCIAL ASPECTS OF INVENTION

Why cities gain at the expense of the country . . . The factory system . . . Small shops multiplied . . . Subdivided labor has passed due bounds and is being modified . . . Tendencies against centralization and monopoly . . . Dwellings united for new services . . . Self-contained houses warmed from a center . . . The literature of invention and discovery as purveyed in public libraries.

The Drift to Cities.

In the closing chapter of this book it may be permissible to glance for a moment at a few of the social and national consequences of invention. While, as we have seen in earlier chapters, the economic gains of ingenuity surpass computation, the work of the inventor has brought in its train evil as well as good, and this evil, with the further march of invention, is being plainly lessened year by year. A century ago about one tenth of the people in North America lived in cities and towns; to-day these centers of population hold nearly one half the families of the continent. Many observers regard this drift from country to city and town with dislike and alarm, without recognizing it to be inevitable. They paint pictures of country folk attracted by the superficial allurements of the city, a poor exchange for the wholesomeness and freedom of life in the country. They argue that with wise education the boys and girls reared on the farm will remain there, greatly to the gain of themselves and the nation. These critics leave out of view the feats of the inventor. Between 1870 and 1880 the self-binding harvester was perfected and introduced. Before its advent six or seven men followed every harvester to tie its shocks of grain. After the self-binder came into vogue, five of these men were no longer needed. Other inventions, planters, corn-shellers, and the like, as economical of labor, have been placed in the farmer’s hands within the past thirty years. The result being that to raise on farms the food for a million men, women and children, a greatly reduced staff in the field suffices to-day in comparison with the number required thirty or forty years ago. And what has become of the country population thus thrown out of work by thews of steel and brass? It has quietly betaken itself to towns and cities where, for the most part, it is manufacturing new comforts and luxuries for all the people, whether in town or country. In 1870 out of 100 wage-earners in the United States, 29 were engaged in manufactures, trade and transportation; in 1900 the corresponding figure had risen to 40. Enter this morning the house of a thrifty farmer or mechanic: you tread on a neat carpet, you see good furniture, a piano in the parlor, a bicycle in the barn. On the walls are attractive pictures, flanked by shelves of books and magazines. In not a few such houses one may find a telephone and electric lamps. As recently as 1870 some of these things did not exist at all, even for the rich. To-day they are enjoyed by millions. So with clothing: it is to-day better and cheaper than ever before. Food, too, is more varied and more wholesome than of yore, thanks to the express train, the quick steamer, the cold storage warehouse. All these agencies of betterment, and many more, are conducted in cities as the centers of capital, industry and population. While invention has, in the main, tended to make cities bigger than ever, it is now modifying that tendency by its rapid trolley lines to suburbs, its steamboat and railroad services constantly quickened in pace and lowered in fares. On the outskirts of Greater New York it is still possible for a wage-earner to buy land for a house and small garden, the burden of rent, liable to yearly increase, being escaped for good and all.

The Factory System and Checks Thereto.

It was in England toward the end of the eighteenth century that inventors first lifted the latch for an industrial revolution. When James Watt devised his steam engine, and its power was applied to spinning and weaving, these tasks were driven from the home to the factory, there to be more economically performed. Other industries followed, all the way from paint grinding to nail making, so that in a few years a profound change came over the field of labor. Under a scheme of subdivided toil the factory hand succeeded to the journeyman who, with a few mates, had split nails or drawn wire in a shop no bigger than some day he might own for himself. With the need to occupy large premises, to install engines and elaborate machinery, the capital of an employer has to be vastly more than of old, creating a new dependence on the part of the workman, and rendering it all but impossible that he should ever have a factory of his own. While the factory system of production is general in America, it is far from universal. Many leading manufactures, those of textiles, of boots and shoes, and so on, are usually conducted in factories, while some important industries, that of clothing, for example, are for the most part carried on at the homes of work people, or in small shops. Massachusetts in 1900, according to the U. S. census of that year, had 200,508 hands in 1078 textile mills and boot and shoe factories. Apart from these industries were 28,102 factories and shops, employing 291,418 hands, an average of but 10.57 each.[44] Taking the United States as a whole, the census for 1900 reports that the hand trades in small shops representing a product of $500 or less each, numbered 127,419. Presumably in all these cases the worker toiled by himself, usually as a repairer or a jobber rather than as a maker of new wares. All the other manufacturing concerns, 512,675 in number, employed on an average only 10.36 persons each. It is clear that the American factory is not as engulfing as many critics believe it to be. In larger measure than is commonly supposed workmen are to-day their own masters, or are busy in shops small enough to give scope to individual ingenuity and skill.

Let us grant that a shoemaker, say in St. Louis, at work in a stall of his own is a better and happier man than if in a nearby factory he fastened eyelets, or burnished heels, day in and day out for years together. While the harm to the toiler wrought by extreme subdivision of labor is plain, its evils are being abated in more ways than one. First of all the productiveness of the modern factory has so augmented the joint dividend of capital and labor that while the working day grows shorter, wages are increased, every earned dollar buying more manufactured wares than ever before. Secondly, in some large railroad and other shops the workmen are given a variety of tasks in succession, so as to be more versatile, more useful in emergencies, than if ever punching steel, or threading bolts. Even if the result of such a plan is to diminish the total output in the course of a year, it is worth while to lose some money that human nature may be redeemed from stupefying monotony of toil. High wages and large dividends cost too much when bought at the expense of hurt to muscle, nerve and brain.

Handicrafts Revived.

And a notable group of artisans, few in number but steadily increasing, with electric motors at their elbows, to-day enjoy complete emancipation from the factory bell. A woodcarver, bookbinder, leather stamper, forger of ornamental iron, rug weaver, potter, lens grinder, or printer, can have to-day a shop of his own and take pleasure in the chosen and constantly varied toil that gives him bread. In their simpler forms the modern lathe, loom, printing press, are cheap enough to be within the means of poor men, while their product when it displays taste and originality is sure of a market. In times past Palissy, Hargreaves, and many another master of a handicraft, has perfected a remarkable invention in a small shop. We may expect the arts to receive golden gifts in the future from the successors of these men, feeling as they do the stimulus of a broadening demand for work executed on new lines of excellence.

Tendencies Against Centralization.

Until within a few years past economic forces in America threatened soon to place its chief industries in the hands of a few men, so strong and unscrupulous as to be able to extort weighty and increasing tribute. For this danger remedies legislative and judicial are being sought, with the prospect of eventual success. In this place it may be allowable to remark how the progress of invention is working hand in hand with the aims of social justice. In the pages immediately preceding this chapter we have seen how cities and towns are working themselves loose from monopoly. A gas supply, on the old basis of manufacture at least, must be a unit, with a strong temptation to overcharge its customers. To-day the lighting field is shared with electricity, showing many isolated plants; when these purvey heat as well as light their rivalry with central stations may become formidable. In American villages and small towns the principal source of light is petroleum, largely controlled by the Standard Oil Company. From its exactions there opens escape as the farmer finds a source of cheap alcohol in his corn, potatoes and beets, even in his unmarketable fruit or damaged grain, ready to give him more light than petroleum ever did, and besides propel his machinery, or carry his crops to the nearest market town. The betterment of common roads throughout the Union proceeds in earnest. As that reform goes forward we may see motor-driven cars and wagons exerting a restraining influence on local railroad rates. Already the steam railroads are facing keen competition from interurban electric lines. Wherever these lines resist absorption, or control, by the steam carriers they serve the farmer so well and cheaply as to be one of the chief boons he has received at the inventor’s hands.

Take one instance chosen from many as striking. Dayton, Ohio, is a center of interurban lines which enfold in their sweep Urbana, Columbus, Hamilton and Cincinnati. Upon 220 miles of these lines the Southern Ohio Express Company picks up cans of milk, cases of eggs, crates of berries, packages of tobacco, from a thousand farmsteads. In the larger business of carrying grain and live stock the expansion is constant, so that the day seems near at hand when the company will find profit in placing a switch at every farm along its lines, sending cars there for everything the farmer has to sell. And the countryman finds Dayton as good a place to buy in as to sell in; its merchants offer better and cheaper wares than are to be had in the home village or the neighboring small town. To-day a farmer or market-gardener, a dairyman or stockbreeder, does not find the smallness of his capital the drawback it would have been ten years ago. With an interurban line passing near his home, or in front of his door, with a cheap telephone at hand, and enjoying a free rural mail delivery, he can sell his produce when he pleases and at the best market prices, paying but a light tax to the middleman, or completing a transaction with a directness that leaves the middleman out altogether.

Steam railroads seek large trainloads to be moved long distances; an electric freight and express service coins dimes into dollars by picking up market baskets, bundles for the seamstress and the laundress, a bunch or two of saplings for the orchard. The trunk lines of America, with their wide-spreading branches, enable merchants in the cities and the larger towns to replenish their counters and shelves every day. Stocks, therefore, need not be so large as of old, when, let us say, a whole winter’s goods were laid in by October. The change reduces the amount of capital required, the outlays for rent and insurance, the liability to shrinkage and deterioration of values. The interurban roads are extending these advantages to the village storekeeper who, in the morning telephones his wants to Toledo, Cleveland, or Detroit; and in the afternoon disposes the ordered wares on his shelves.[45]

New Domestic Architecture.

American dwelling houses, whether in city or country, have within forty years been much improved in plan and equipment. To speak only of dwellings in cities, we may note how designers and inventors have promoted comfort and convenience, healthfulness and cheer. At the close of the Civil War an ordinary house in Philadelphia, or Chicago, as it left the builder’s hands was little else than a bare box. Stoves for warming and cooking had to be brought into it, wardrobes heavy and clumsy were placed beside its walls, cupboards meant to be moved and not moved easily held the raiment and table linen. In rented houses the gas fixtures might belong to the tenant; when he took them away ugly breaks appeared in walls and ceilings. To-day all this is of the past: in important details the design of the mansion is embodied in dwellings comparatively small. Furnaces for heating, ranges for cooking, form part and parcel of the building; fixtures for gas and electricity, yielding both light and heat, are provided just as water faucets are; every bedroom has its clothes closet instead of the lumbering wardrobe. In the kitchen we find dressers and china closets built into the walls; the laundry has stationary washtubs and, in some cases, a drying room as well, so that the laundress does not care should it rain on washing day. The aim throughout is that the house and its equipment shall as far as possible make up a unit, that the labor of housekeeping be minimized to the utmost by a judicious outlay of capital when the house is built.

Electricity at Home.

Since 1900 the American householder, as well as the American business man, has fairly awakened to what the telephone can do for him. It is estimated that in 1905 the telephone in the United States earned four times as much as the telegraph. The day is at hand when every household but the poorest will enjoy the wonderful gift of Professor Bell. In somewhat the same fashion it is dawning upon the public that electricity stands ready to perform other services, each minor, but all, in the aggregate, going far to promote health and comfort at home.

At Schenectady, New York, Mr. H. W. Hillman, apart from heating in winter, has adopted electricity for many household tasks, with results described and illustrated in the Technical World, Chicago, July, 1906. His kitchen outfit for a family of five persons comprises an electric table, oven, griddle-cake cooker, meat broiler, cereal cooker, water heater, egg boiler, potato steamer, frying pan, coffee percolator, and a stove for ordinary cooking utensils. A three pound nickel plated electric iron is provided for the laundry. In the dining-room is an electric chafing dish and a percolator. On the verandah and in the den are electric cigar lighters. In the sewing-room the machine is driven by an electric motor. The bathroom has an electric mug which heats water for shaving in less than a minute; in chilly weather the luminous radiator yields just the slight heat which ensures comfort instead of discomfort. Of course, throughout the house electric lamps furnish light with the maximum of convenience and wholesomeness, the minimum of risk.

How does this service compare in cost with the employment of coal and gas? With coal at $6.50 a ton, and gas at $1.30 per thousand cubic feet, the average monthly expense was formerly $6.00; with electricity the bills are but 69 cents more per month, a mere trifle in comparison with the gain in comfort, the saving of drudgery, the promotion of cleanliness. The rate for electricity used for lighting is 10 cents per kilowatt hour, for heating only half that rate.

Mr. Hillman does not use electric heat for ordinary warming: it would cost him too much. A good many people are puzzled by the fact that an electric current, which yields a perfect light at a reasonable price, should in the sister task of heating fail in rivalry with a common stove or furnace. To solve this puzzle let us place our hands above a cluster of 15 Edison incandescent lamps, each of 16 candle power, representing one horse power, yet emitting no more heat than if three ounces of coal were slowly burning away in the course of an hour. This electricity may cost us ten cents an hour, the coal costs but the fifteenth part of one cent. In producing mechanical motion at a power-house, the engines waste at least ninety per cent. of the applied heat. To this heavy tax must be added the expenses of distribution, administration and maintenance. Until, therefore, the electrician reaches a mode of creating his current from heat without the enormous losses of present practice, we cannot look to him for a system of general heating. A word has already been said in this book about methods of district heating by steam. Another plan is worthy of mention. In Brooklyn the Morris Building Company supplies from a central plant fifty-two dwellings with hot water which serves not only for heating, but for cooking and washing also. The water is heated in part by live steam, in part by exhausts from steam engines.

Suggested Exhibits.

Such an experiment as this, the appliances at work for Mr. Hillman, suggest exhibits which might form part of the premises of agricultural colleges and technical schools. These establishments usually require for their officers such dwellings as are not too large and costly for ordinary householders. These dwellings, carefully designed and equipped, might serve as examples of the best practice in building, planning and appointment; in sound methods of heating from a central plant. At suitable times they might be open to public inspection. They might range in cost from $1,000 to $5,000, the cheapest to be built of wood, others to be built in brick, stone, or concrete. All the furniture and fittings to be chosen with an eye to wholesomeness, durability, and maintenance with the least labor possible. Each house should contain in its main room a card telling the cost of the building, with estimates of cost if executed in other materials. On occasion this plan might be extended to the contents of houses, each item on show days to be duly labeled. A series of such houses would tend to bring ordinary house-planning and housekeeping to the level of the best. Many books and journals offer architectural diagrams which few can understand, but everybody can see how attractive a good plan is when realized in a house to which he pays a leisurely visit. At Expositions, such as those of Chicago and St. Louis, the appeal of the architect and the exhibitor is rather to wonder than to utility. He shows us schlosses from Germany, palaces from Italy, châteaux from France, all appointed with costly magnificence. But while the average American wage is eleven dollars a week these displays can do little good as models for imitation.

NOTE ON THE LITERATURE OF INVENTION AND DISCOVERY

INDEX

• Abbe, Ernst, portrait, facing 182; Jena glass, 181; at first ignorant of practical optics, 293.
• Aboriginal art, National Museum, Washington, 106; tools, 89.
• Abrasion, manganese steel resists, 171.
• Accident, Nobel profits by an, 411.
• Accidental observation, 289.
• Acheson, E. G., carborundum, 101.
• Achromatism, Newton on, 254.
• Acknowledgments, xxi.
• Actinium, four derivatives, 200.
• Adams, Frank D., proves marble plastic, 196.
• Adams, John Couch, discovers Neptune, 378.
• Aeronautics, 129.
• Air, compressed. See Compressed air; brake catechism, R. H. Blackall, 428; chamber of pumps, 252; churned in telescopic tube, 348; compressors, 424-427; and multiple cylinders for, 372; turbines, reversed as, 372; conducting when traversed by X-ray, 282; warm, and smoke protect from lightning, 294; hardening steel, 172; jet for machine tools, 173.
• Aladdin oven, 189, 190.
• Alchemy and radio-activity, 203.
• Alcohol, cheap, 452; engines, 468; for lighting, 157; lamp with hood, 158.
• Algonquin art, 115.
• Allan Line steamers driven by turbines, 455, 456.
• Allen, Leicester, on invention, 268.
• Allis-Chalmers steam engines, facing 448, facing 452; Francis vertical turbine, 446.
• Alloy for electro-magnets, 173.
• Alloys, influence of minute admixtures, 175; made by pressure, W. Spring, 201; Weston’s for electrical measurers, 232, 234; anti-friction, 174.
• Alternating currents used as produced, 346.
• Alum crystal broken and repaired, 193, 194.
• Aluminium discovered by Wohler, 143; properties, 143, 144, 145; separated from its compounds by C. M. Hall; uses, 144, 145; in lithography, 144; in producing great heat, 145; alloys, 145; as electrical conductor, 145; in iron manufacture, 145; mandolin pressed, 185.
• Alundum wheels, 101.
• American Library Association, aids to readers and students, 487.
• Ammeter, Weston’s, 233.
• Ammonia sulphate from Mond plant, 461.
• Analogy as a guide, 366-369.
• Anderson, Sir William, on formulae, 383.
• Andrews’ discovery of continuity in states of matter, 212.
• Angles replaced by curves, 48-51.
• Animal frame repeated in machinery, 250.
• Annealing steel, 168.
• Annular drills, 91-93.
• Anthony, W. A., on invention, 268.
• Anti-friction alloys, 174.
• Ants, Warrior, nest, 260.
• Aquarium, New York, 76.
• Arbor hollow, cooled, 88.
• Arc-lamp, 160; inverted, 75, 76.
• Arch, its structural advantage, 42; discussed by W. P. P. Longfellow, 43; as dam, 45; of skull, 250; Saracenic, 43; bridge, Niagara, 31.
• Arches inverted as gulleys, and anchorage, 45; pointed, 43; united as dome, 355.
• Architecture, Egyptian, 114; Japanese, Ralph Adams Cram, 114, foot-note; materials, 115; modern, Russell Sturgis on, 119; new domestic, 483.
• Areas, irregular, measured, 347.
• Argon discovered by Lord Rayleigh, 213.
• Arm holding ball, 256.
• Arrows, feathers in, 65.
• Articulated water-pipe, 259.
• Ashes, conveyors for, 447.
• Astatic needles, 149.
• Astronomy advanced by new instruments, 230; aided by Carnegie Institution, 277; co-operation in, E. C. Pickering, 278; measurements in, 229, 230.
• Atkinson, Edward, Aladdin oven, 189; on window glass, 72; “Science of nutrition,” 190; tendencies in manufacturing, 480, foot-note.
• Atmosphere, gases of, 213, 214.
• Atom, size, 130-32.
• Atwater, W. O., on foods, 243; on energy value of foods, 264; aided for researches on foods, 277.
• Austenite, 164.
• Automatic devices, 329-337; at Interborough Power-house, 447; stokers, 450.
• Automobile design, 117; gasoline driven, construction, 468; balanced cylinders, 464; racing, 66; radiator, 87.
• Axe tells story, Wm. Metcalf, 377.
• Axles, hollow, 40; cooled, 88.
• Baboons teach Hottentots and Bushmen, 136, 259.
• Bain, Alexander, on identifying faculty, 360; on passion for experiment, 304; on sound judgment, 385.
• Balance, beginnings, 208; ancient Egyptian, 219, 220; Lavoisier, 209; interferometer applied to, 217; measures irregular areas, 347; requirements for, 220; at its best, 221.
• Balance wheel in time-pieces, 222; Earnshaw’s compensated, 223.
• Balances, Bureau of Standards, 235.
• Bale, Geo. R., Modern Foundry practice, 176.
• Ball-and-socket joints, 251.
• Ball bearings, 47, 48.
• “Baltic,” steamer, 127.
• Baltimore truss, 25.
• Bamboo, its uses, 141; for walls and roofs, 39; for water carriage, 45; filament for electric lamp, 140.
• Bank-swallow, lesson from, 297.
• Bar of metal shaped by pressure, 326; for reinforcing concrete, 436, 437.
• Bark vessel and clay derivative, 115.
• Barnard, E. E., detects a double star, 285.
• Barrel pressed steel, 185.
• Barrett, W. F., experiments with iron alloys, 173.
• Basin, experimental, for ship models, 54, 55; U. S. Navy, facing 54.
• Baskerville, Charles, researches in thorium, 200.
• Basket, Bilhoola, 110, 111; Pomo, 109; bowl, Yokut, 112.
• Baskets imitated from fish traps, 116; materials for, 109; waterproof, 143.
• Basketry, materials for, 142; Indian, Otis T. Mason, 110, 142.
• Bates, W. H., explains protective resemblances, 289.
• Bearings, ball, 47, 48; roller, 47, 49.
• Beaufoy, Marc, on ship resistances, 52.
• Beauty through use, 104, 105.
• Beaver dams, ingenuity of, 265; tooth, 258.
• Becquerel, Henri, researches in phosphorescence, 199.
• Beethoven composing, 300.
• Begonia, tuberous, produced, 249.
• Bell, Alexander Graham, portrait frontispiece, facing 2, his Brantford homestead; transmission of sound by light, 393-400; telephone, 393, foot-note, 293.
• Bell, Sir I. L., manufacture iron and steel, 177.
• Bell, Louis, “Art of Illumination”, 229, foot-note.
• Bergman, Torbern, analyzes steel, 163.
• Bessemer, Henry, portrait facing 402; early tasks, makes bronze powders, 401; improves sugar-cane mill, 402; begins experiments with iron, 403; first converter, 404; illustrated, 406; pulverizes materials for glass, 407; on “a little knowledge,” 408; improves the drying of oils, 409; process, 164; steel rails, 14.
• Bicycle wheel, 382.
• Bi-focal spectacles, 85.
• Bilgram, Hugo, gearing, 67.
• Binding machinery, direct, 342.
• Binocular glasses, 81, 82.
• Biological observations, Karl Pearson on, 277; laboratories, 276.
• Birch-bark vessels, 115.
• Bird’s feet covered with dirt observed by Darwin, 280.
• Bilhoola basket, 110, 111.
• Birds and reptiles, a link discovered by E. S. Morse, 287; flight of, studied, 263.
• Bismuth pure and united with tellurium, 175.
• Blackall, R. H., air-brake catechism, 428.
• Blanchard lathe, 95-97.
• Blast furnaces curved, 50; gases for power, 462.
• Blasting, its utility, 411.
• Blenkinsop’s locomotive, 345.
• Bliss press work, 184-186; forming die, 184; gears, 67.
• Blocks, hollow concrete, 433-435.
• Blood, circulation of, 256; pressure, experiments on, 272.
• Blowing machinery, Homestead, Pa., 415.
• Boat, canal, diminishes in resistance when quickened, 283.
• Boiler corrugated, 88; economy, 450; outside furnace, 381; plate cut, 91; copper, how improved or worsened, 176.
• Boiling point water lowered as atmospheric pressure lessens, 375.
• Boivin burner for alcohol, 157.
• Bolometer, Langley’s, 225.
• Bookcases, sectional, 351.
• Book-shelves with camber, laden and unladen, 36, 37, 254.
• Books reproduced by photography, 324.
• Borderlands of knowledge, Lord Rayleigh on, 275.
• Bourne, George, on beauty of tools, 105.
• Bow-puller studied by E. S. Morse, 288.
• Bowstring bridge, 31; Philadelphia, 32; invented by Alex. Nasmyth, 308.
• Brace, ratchet bit, 90.
• Brachiopods studied by E. S. Morse, 288.
• Brahe, Tycho, observations, 229.
• Brain in co-ordination, 257; disease, localization, 378; disease treated, 272.
• Brakes, Westinghouse, 428.
• Bramah, planer, 98.
• Brashear, J. A., concave plates for Rowland, 237; optical surfaces produced, 83, 84; lenses and mirrors for interferometer, 217.
• Breakwaters curved, 51; concrete, 430.
• Breech-loader, 379.
• Bricks shaped by pressure, 325.
• Brick-work outlines, 112.
• Bridge, concrete, at St. Denis, 431; Forest Park, St. Louis, 444; Memorial, Washington, D. C., 444; continuous girder, 32, 34; deck, 24; pipe-arch, Rock Creek, 41; and at Saxonville, Mass., 41, 42; Plauen, Germany, 42, 43; rollers, 38; St. Louis, 31; strains studied, 25; through, 24; Victoria, Montreal, 26-28; Whipple, 25.
• Bridges, 18-38; cantilever, 26; near Quebec, 29, 30; Kentucky river, 30, 31; esthetic designs, 38; railroad, 23; suspension, 32.
• Bronze powders, Bessemer’s, 401.
• Browne, Addison, on original research, 273.
• Brush, Charles F., arc-lamp, 160.
• Bubbles rising in liquid, 127, 128; sharpen files, 147.
• Buchanan, William, plans famous engine, 15.
• Buffalo trails give hints to railroad engineers, 259.
• Buffon on invention, 271.
• Bullock cart with solid wheels, 47.
• Bulrush section, 251.
• Bureau of Ethnology reports, 107, foot-note.
• Bureau of Standards, Washington, 234-236.
• Burke, Charles G., telegraphic code, 352, 353; simplified signals, 354.
• Burner, Boivin, for alcohol, 157.
• Burroughs, John, on observation, 281.
• Bushmen learn from baboons, 136.
• Buttresses for arches, 43.
• Cabin, disadvantages of its size, 130.
• Cables, electric, X-rays examine, 327.
• Cactus adapts itself to environment, 248.
• Cadmium rays, 218.
• Caliper, micrometer, 236.
• Camber in book-shelves, 36, 37, 254; in bridges, 37.
• Campbell, H. H., Manufacture iron and steel, 177.
• Canada, roofs in, 118, 119.
• Canal and circulation blood, 256; boat diminishes in resistance when quickened, 282.
• Candles copied in gas-burners, 116; and in electric lamps, 117.
• Cantilever, 26; bridges, 26-31; where best, 35.
• Capital more necessary under factory system than before, 480.
• Carbon dioxide detected in flue gases, 470.
• Carbon in steel, 163, 164; filament graphitized, 158.
• Carborundum wheels, 101, 102.
• Carburetor, 466.
• Cards for catalogues, 349, for notes, 350.
• Carex root in basketry, 110, 143.
• Cargo steamer, 59, 61.
• Carnegie Institution for Original Research, 276-278; Library, Pittsburg, 486.
• Carpenter, Rolla C., “Heating and ventilating buildings,” 472.
• Cartilage in joints, 251.
• Carving chisels and gouges, 90; by air hammers, 418.
• Catenary curve, 43.
• Cathode rays, 198.
• Cattle-breeding, 249.
• Caves as store-houses, 137; Virginia and Kentucky, 123, 246.
• Cedar for basketry, 110, 142.
• Ceiling, heating coils on, 86; white, as reflector, 76.
• Cellulose filaments for lamps, 261.
• Celts lend forms to bronze, 116.
• Cement, natural, 430; Portland, 430; Roman, 429.
• Cementite, 164.
• Central stations, telephonic, 257; management, Edison Electric Co., Brooklyn, 474.
• Centralization, tendencies, 481.
• Cerium for gas mantle, 156.
• Chain suspended, 43, 44.
• Chaldean records of eclipses, 229.
• Channeling machine, Saunders, 342.
• Chanute, Octave, on invention, 268.
• Character in research, Tyndall on, 364.
• Charcoal, 125; produces vacuum, 328.
• Chemical synthesis, 374; theory enlarged by discovery of radio-activity, 203; triggers, 337.
• Chemistry of living bodies, 262.
• Chimneys, why shorter, 448; reinforced concrete, 440, 441.
• Chisel, carving, 90; cold, of two kinds steel, 167.
• Chittenden, L. E., lesson from bank-swallow, 297.
• Church, Duane H., inventor watch-making machines, 222.
• Church of St. Remy, 43; Notre Dame de Bonsecours, Montreal, 118.
• Cinders, large and small on hearth, 120.
• Cities, why they gain at expense of country, 478; sites for, 246.
• “Class in Geometry,” 122.
• Classification literature, Melvil Dewey, 352.
• Clay, molded, 102, 103; in the arts, 139.
• Cleveland Stone Co., compressed air plant, 427.
• Clifton suspension bridge, anchorage, 45.
• Clipper ships, 57.
• Cloaca Maxima, Rome, 45.
• Clocks, Riefler, 223, 224; self-winding, 330.
• Coal, glowing, broken into fragments, 120; cutter, Ingersoll, 418; testing plant, U. S. Geological Survey, foot-note, 241; washer, 151.
• Cobbett, William, on writing as an exciter of thought, 300.
• Coding in telegraphy, 352-354; in invention, 317.
• Coherer, origin of, 147.
• Coignet netting for concrete, 442.
• Coils, heating, 86.
• Collections, value of, 288.
• Collodion, Nobel utilizes, 411.
• Color dispersion, 180.
• Columns of bridge, 23; hollow, 39.
• Combinability of matter, 194.
• Compass deflected by electricity, 230, 231, 290.
• Compasses as truss model, 20; liquid, 149.
• Compensating devices, 148.
• Complexity in machine may be necessary, 341.
• Compressed air, 417-428; drives tools, 417; coal cutter, 418; for hammers, facing 418, 419; air tools first used by dentists, 419; drill used as hammer, wood-borer, 420; ramming, paving, tamping, 420; drives away chips, cools cutter, lifts water, 421; works pumps; for painting, 422, 423; for cleansing, 423; sandblast, 424, 425; air compressors, 424-427; inter- and outer-cooler, 426; heaters for, 426; in quarrying, 427; Westinghouse brakes and signals, 428; for transmitting power, 348.
• Compression in building, 8; members must be of rigid material, 19.
• Compressors, air, 424-427; Parsons‘, 372.
• Conch-shells as pitchers, 108.
• Concrete and its reinforcement, 429-445; vast uses concrete, 431; bridge at St. Denis; desirable qualities, 431; silos, 431, 432; residence, Fort Thomas, Ky., 432 and facing 432; for small, cheap dwellings, 432; blocks, general manufacture, 433, 434; reinforcement introduced by Monier, 435; bars for, 436, 437; Monier netting; expanded metal, 437, 438; molds, 438; Pugh Building, Cincinnati, grain elevators, bins, 439; chimneys, incorrodibility, 440, 441; tanks, reservoirs, 441, 442; Coignet netting, 442; conduit, water-pipes, 442; culvert, N. Y. Subway, 443; bridges, 443-445; strengthened by crushed stone, 240; “Concrete Construction about the Home and on the Farm,” 431, foot-note.
• Condensers, steam engines, 87; Weighton’s, 452.
• Conduit, reinforced concrete, 442.
• Cones, similar, vary in contents as cube of like dimensions, 376.
• Confectioners’ ornaments, 325.
• Contents, solid, ascertained, 343, 344.
• Continuous girder bridge, 32, 34.
• Contours as decided by material, 111.
• Contraction withstood, 88.
• Contraries, profit in, 379.
• Convenience in machines, 106.
• Converse inventions, 70.
• Conveyors, 69.
• Cook, O. F., on interest as prime factor in discovery, 306.
• Cooking box, Norwegian, 189.
• Co-ordination, brain, 257; machinery, research, in armies, 194.
• Copernicus as discoverer, 270, 359.
• Copper in electric bath, 103; reduced in electrical conductivity by admixtures, 175; for boilers, affected by union with antimony, arsenic, bismuth, 176.
• Corals fed, 123.
• Corona observed, 293.
• Corrodibility, slight, of Jena glass, 183; of steel reduced, 167; of steel in concrete, 441.
• Corrugated boiler, fire-boxes, 88.
• Cotton seed utilized, 149.
• Counterbalance, hydraulic pressure, 371.
• Cowpox prevents smallpox, 295.
• Cram, Ralph Adams, on Japanese wood-work, 113; “Japanese Architecture,” 114, foot-note.
• Craver, Harrison W., Carnegie Library, Pittsburg, 486.
• Crookes, Sir W., on precise measurement, 214; tube, 198; radiometer modified by Nichols, 226.
• Cross-fertilization of sciences, Maxwell, 275.
• Cross-ties introduced on railroads, 13; steel, Pittsburg, 17.
• Croton Dam, concrete, 431.
• Crow gets at clam, 369.
• Crystal, alum, broken and repaired, 193, 194, 357.
• Crystallization iron and steel, J. W. Mellor, 177.
• Cube subdivided, 121, 122; root extractor, 375, 376.
• Cubit, origin, 209.
• Culvert, reinforced concrete, 443.
• Cunard steamers, new, 128; driven by turbines, 456.
• Curie, Pierre, and wife, discover radium, 199.
• Curves replace angles, 48-51.
• Cushing, F. H., on Zuni water vessels, 108.
• Cutters, lathe, 90; milling, 98, 100, 101.
• Cylinder, hollow, for piping, 45; for boilers, 46; strength of, in organic forms, 250, 251.
• Cypress, deciduous, 247, 248.
• Dacotah fire-drill, 94.
• Daguerre’s discovery of photography, 304, 305.
• Dam in arched form, 45; across Bear Valley, 44.
• Darwin, Charles, as observer, 280; as questioner, 356; facts and arguments, 359; on directive worth of theory, 356.
• Davenport, C. B., experimental evolution, 276.
• Da Vinci, Leonardo, artist and inventor, 308; suspended wheel, 382.
• Dawson, Bernard, open hearth furnace, 164, 165.
• Dayton, Ohio, as center interurban electric lines, 482.
• Deck bridge, 24.
• De Laval, steam turbine, 452, 453.
• Delta metal, Alex. Dick, 325.
• Dentists first to use air tools, 419.
• De Rochas, Beau, gas engine, 462.
• Detachable parts of tools and so on, 239.
• De Vries, Hugo, discovers evolution by leaps, 276.
• Dewar, James, non-conducting glass vessels, 375; produces vacuum, 327.
• Dewey, Melvil, decimal classification literature, 352.
• Dexter feeding mechanism, 331.
• Diamond, combustibility of, 357; artificial, H. Moissan, 265; drills, 92; separated from other stones, 150.
• Dick, Alex., inventor Delta metal, 325.
• Dies, steel, 175.
• Diesel oil engine, 466.
• Diffusion of constituents air, 262.
• Digestion, impaired, treated with lining of ostrich stomach, 295.
• Digit as measure, 209.
• Directive paths, 332.
• Directness as an aim in design, 342.
• Directory iron and steel works, J. M. Swank, 178.
• Discovery, character in, 364; chief impulse to, 306; method of, 300; Faraday on, 363, 364; Jevons on, 364.
• Discursiveness, Thomas Young, 365.
• Disease, functional, 378; skin, treated with Uviol lamp, 183; brain, localization, 378.
• Dispersion of color, 180.
• Distribution motive power, direct, 342.
• District heating by steam, 448; Lockport, N. Y., advantages, 473; by water, 485.
• Division of labor modified, 480.
• Dodge & Day effect economies, 244.
• Dogmatism, Tyndall, 363.
• Dollond lenses, 254, 255.
• Dome built of arches, 355; of ants’ nest, 260.
• Domestic architecture, new, 483.
• Douglas, James, on automatic machinery in metallurgy, 332.
• Downdraft furnace, 381.
• Dowson producer gas for lightning, 157.
• Draft, mechanical, 380, 448, 472.
• Drama, nature as, 356.
• Drawing, James Nasmyth on, 308.
• Dredges, hydraulic, 259.
• Drill, diamond, 92; fire, Dacotah, 94; steels, 418; air, used as hammer, 420.
• Drills in rifle-making, 282; multiple, 290; ring, 91-93; twist, 93.
• Drilling in lathe, two methods, 370.
• Drucklieb, C., sandblast, 424, 425.
• Drummond, Thomas, lime-light, 155.
• Dry blast process, Gayley, 165.
• Dudley, C. B., anti-friction alloys, 175.
• Dudley, Plimmon H., portrait, facing 14; forms of rails, 14; on steel for rails, 169.
• Dulong and Petit, non-conducting glass vessels, 375.
• Duncan, R. K., “The New Knowledge,” 204, foot-note.
• Dundonald, Lord, gas flame, 280; down-draft furnace, 381.
• Durand, W. F., on ships varying in size, 128.
• Dust, 125; combustible, 125.
• Dvorak sound-mill, 132.
• Dwellings, suggested exhibits, 485.
• Dyes tested with Uviol lamp, 183.
• Dynamite invented by Nobel, 410.
• Eads, J. B., Mississippi jetties, 283; St. Louis bridge, 31, 41, 127.
• Ear structure, 257.
• Earnshaw’s compensated balance wheel, 223.
• Earth, age of, 356; sculpture, 122.
• Eclipses, Chaldeans observed, 229.
• Economizer, steam engine, 449.
• Economy, aim in invention, 341; tested by experience, 383.
• Edison, portrait, facing 374; as an organizer, 414; bamboo filament, 140; incandescent lamp, 158; on concrete for cheap dwellings, 432; separates iron from sand, 150; storage cell, 374; store-house, 153; tells how he invented phonograph, 310; latest phonograph, 312.
• Education of eyes, ears and hands, 300.
• Eel, electric, 257.
• Egyptian architecture, 114.
• Elasticity explained, 358.
• Electric cables, X-rays examine, 327; conductors and non-conductors, 202; dynamo and its converse, the motor, 373; eel, 257; heat for cooking, 188; heat, why too dear for ordinary warming, 484; heater, Gold’s, 87; lamps in candle shapes, 117; lighting, 158-162; lighting, General Electric Co.‘s researches, 416; lighting current economized by uniform voltage, 243; locomotive, General Electric Co., 128, 129, 415, 476, facing 476; motor aids handicraftsmen, 481; traction, 476; interurban, 482.
• Electrical advances, Lord Rayleigh on, 274; conductor, copper as, affected by admixtures, 175; conductor, iron as, 173; contact, imperfect, leads to invention of microphone and coherer, 146; experiments, Faraday’s simple, 391; reversibility, 373; sparks useful, 147; Testing Laboratories, N. Y., 242; thermometry, 225, 226; units adopted, 239.
• Electricity for all possible services, 474; in the household, 484; for power transmission, 348; may be produced by food, 264; measured, 230-234; measures heat, 373; modifies properties, 140; brings new properties into view, 197; used as produced, 346.
• Electrolysis and its converse, 373, 374.
• Electro-magnetism discovered by Oersted, 230, 290, 373.
• Electro-magnets curved, 50; alloy for, 173.
• Electro-plating and its converse, 374.
• Electrons, Joseph J. Thomson on, 132; form cathode rays, and parts of atoms, 198.
• Elements of chemist probably a single substance, 357.
• Elevator cages, 40; grain, 68; reinforced concrete, 439.
• Elliptical hand-hole plates, 46.
• Embossing machines curved, 50.
• Embroidery machine, 319.
• Emery testing apparatus, 242.
• Emery wheels, 101, 102.
• Energy, molecule as reservoir of, 131; potential, 358.
• Engineering problems, Osborne Reynolds on, 274; principles in vegetation, 247.
• Entrance of ships, 53.
• Ericsson, John, inventive from childhood, 303; Life, 98; Monitor, 97, 98.
• Erie City boiler, 46.
• Eskimo ingenuity, 106; pelts and bird-skins, 138; skin scraper, 91.
• Esthetic design of bridges, D. A. Molitor, 38.
• Ether may give birth to matter, 358.
• Ethnology, Bureau of, reports, 107, foot-note.
• Everett, Harold A., acknowledgment to, 64.
• Evolution proved by Darwin and Wallace, 267; chemical elements, and of stars, 204; the master key, 357; experimental, 276.
• Ewart detachable link belting, 69.
• Exhibits of dwellings suggested, 485.
• Expanded steel, 437, 438.
• Expansion withstood, 88.
• Experiment, 299-328; passion for, Bain on, 304.
• Experimental evolution, 276.
• Explanation, the longing for, 355.
• Explosions, retarded effects, 195.
• Explosives, utility of, 409, 411.
• Eye structure, 257; and Dollond lenses, 254, 255.
• Faber talking machine, 343.
• Factory system, rise of, 479; checks to, 480.
• Faculty, identifying, 360; knitting, 359.
• Fan blower, converse of windmill, 371; for furnaces, 372; for pneumatic tubes, 373; for heating and ventilating, 380, 472; screw form, 69.
• Fanning mill, 150.
• Fansler, Percival E., acknowledgment to, xxi.
• Fant, Thomas E., acknowledgment, xxi.
• Faraday as an observer, 279; discovery magneto-electricity, 373; discovery specific inductive capacity, 212; magnetic researches, 201; on discovery, 363, 364; on observations of untrained men, 294; on radiant matter, 204-206; method of working, 389; on experiment, 390; simple apparatus for experiment, 390; orderliness, 391; imagines lines of force, 392.
• Farm implements should be simple, 340.
• Fathom, origin, 209.
• Feathers have advanced birds in scale of life, 250; in arrows, 65.
• Feeding mechanism, Dexter, 331.
• Fellows gear shaper, 67.
• Ferguson, Mephan, water-pipe, 45.
• Ferrite, 164.
• Ferro-titanium arc-lamp, 161.
• Fibre, indurated, 322.
• Filaments for incandescent lamps, 261.
• Files sharpened by bubbles, 147.
• Fire kindling, 125; modifies properties, 140; brings properties into view, 197.
• Fire-arms rifled, 65.
• Fire-boxes, Morison corrugated, 88.
• Fire-drill, Dacotah, 94.
• Fire-fly, Cuban, 263.
• Fire-lighter, spiral, 41, 42.
• Fire-syringe, 467.
• Fischer, L. A., acknowledgment to, xxi.
• Fishing-rod, in steel tubing, 41.
• Flaming arc-lamp, 160.
• Flesh frozen for slicing, 326.
• Flight, mechanical, 262.
• Flint, aboriginal, 89; for tools and weapons, 137; polished by sand, 424; burnt for white ware, 290.
• Flour milling, Hungarian, 150.
• Flywheel encased to lessen air resistance, 67.
• Folk observation, 294-297.
• Food, how chosen, 135, 136; energy value of, 264; investigated by W. O. Atwater, 243; with aid from Carnegie Institution, 277.
• Foot measure, origin, 209; skeleton, 250.
• Foresight in invention, 265.
• Form, 5-119; conferred, 103, 104; in plastic arts, 103; to lessen resistance to motion, 65-71.
• Fortifications, curves in, 51.
• Foster, Sir Michael, on original research in medicine, 269.
• Foundries, iron, list, last paragraph, 178.
• Foundry practice, modern, Geo. R. Bale, 176; compressed air in, 420.
• Francis vertical turbine, 446.
• Franklin, Benjamin, bi-focal spectacles, 85; stove, 85; proves lightning to be electricity, 360.
• Fraunhofer invents spectroscope, 284.
• Freeman-Mitford, “Bamboo Garden,” quoted, 141.
• Freezing earth to stop leak, 326; water expands, 375.
• Friction, Beauchamp Towers’ researches, 274; alloys for minimizing, 174.
• Frost wedges off stone, 123.
• Froude, Edmund, on ship resistances, 53.
• Fuels which serve gas engines better than steam engines, 466.
• Furnace inside boiler, 381; downdraft, 381.
• Furniture embodied with house, 483; lumber for, bent and seasoned at once, 343.
• Galileo invents pendulum, 222.
• Gallows-pipe, 86.
• Galton, Francis, on sharp sight and visual memory, 281.
• Galvanometer, Maxwell’s, Kelvin’s, 231.
• Gang saws, 290.
• Garden squirt, 371.
• Gas exploded by electric spark, 147; from a candle, 457, 458; engines, 458, 462-466; producer, 459-461; Mond gas, 461; blast furnace, 462; for heat, light and power, 475; grates imitate maple or charcoal, 117; lighting, 154, 155, 280, 457; mantle, 155-59; producer, Loomis, 382; Taylor, 460; turbine projected, 415.
• Gases, kinetic theory of, 357; of the atmosphere, Sir W. Ramsay, 214, foot-note.
• Gasoline engines, 468.
• Gayley dry blast process, 165.
• Gearing, 67.
• Geissler tubes, 198.
• General Electric Co., locomotive, 415, 476, facing 476; researches in lighting, 416.
• Generalization in discovery, 306; Simon Newcomb on need of, 277.
• Geological studies aided by Carnegie Institution, 277; Survey, U. S., coal testing plant, 241, foot-note.
• Geology, elementary, 122, 123; records of, 377; study of, 356.
• Geometry, Class in, 122.
• Germany leads in original research, 275.
• Germs destroyed with Uviol lamps, 183.
• Giffard injector, 347.
• Gill, Sir David, on double star discovery and measurement, 286.
• Girders, 10-12; box, 39; Hennebique concrete, 437.
• Glacial action observed, 294; Darwin fails to observe, 280.
• Glanz-stoff, artificial silk, 261.
• Glass, binocular, 81, 82; Jena, see Jena; nickel steel of equal expansibility with, when heated, 170; prismatic and ribbed, 73, 74; rough, for windows, 72; total reflection, 77-82; making, Bessemer pulverizes materials for, 407.
• Gledhill, J. M., on high-speed tool steels, 172.
• Globes, Holophane, 78-81.
• Gluttony, Indian, a cause, 137.
• Glycerine utilized, 149.
• Gold betokened by a bush, 296; extraction of, 332; solid, diffuses in solid lead, 201; alloyed with bismuth has no tenacity, 175.
• Gold’s electric heater, 87.
• Goldschmidt, Dr., produces great heat from iron oxide and aluminium, 145.
• Goodyear, C., discovers vulcanization of rubber, 289.
• Gothic cathedrals, 43.
• Gouges, carving, 90.
• Gourd as pitcher, 108; derived pottery forms, 109.
• Graham, Thomas, on states of matter, 201.
• Grain dried for keeping, 137; elevator, 68; separated from chaff, 150.
• Graphitized carbon filament, 158.
• Gravitation, law of, Newton’s discovery, 387.
• Gravity as motor in mills and post-offices, 321, 322; balanced, 148; brings rain to valley, 245; specific, learned, 344.
• Gray, Elisha, telautograph, 315.
• Greek sculpture, 114.
• Gribeauval, Gen., interchangeability, 238.
• Griffin, Charles, on convenience in machines, 106.
• Grinding lenses, 83, 84.
• Guesses precede theories, 358.
• Guillaume, C. E., invents invar, 169; his unit of measurement, 213.
• Gun, built-up, 252, 253; breech-loading, 379; curved, 50; drilled, 93.
• Gunpowder cakes, 125.
• Guthe, K. E., steatite fibres, 235.
• Hadfield, R. A., alloy for electro-magnets, 173; manganese steel, 171.
• Haida squaw mats, 116.
• Haitinger, Ludwig, discovers cerium in gas-mantle, 156.
• Hall, Asaph, discovers two satellites of Mars, 286.
• Hall, Charles M., produces aluminium, 143.
• Hall, F. W., mechanical treatment steel (see under Harbord), 177.
• Halsey, T. S., on premium plans for wages, 244, foot-note.
• Hammer, air, 419; drill used as, 420; wasp using pebble as, 260.
• Hand-breadth as measure, 209.
• Hand-hole plates, Erie City boiler, 46.
• Handicrafts revived, 481.
• Handwork should not be directly imitated in machine design, 342.
• Harbord, F. W., Metallurgy of steel, 177.
• Harcourt lamp, using pentane, 226.
• Harcourt, Rev. Vernon, makes new glass, 181.
• Hargreaves, James, invents spinning jenny, 290.
• Harris compressed-air pump, 422.
• Harris rotary press, 48.
• Harrow simple, 340.
• Harvester, self-binding, 478.
• Harvey, discovery movements heart and blood, 267, 272, 359.
• Haymaking and law of size, 130.
• Heart and built-up gun, 252, 253.
• Heat, as motion, 358; conservation of, 250; converted into work, 263; economy, 85, 86; electric, for cooking, 188; light and motive power from central stations, 473-474, 481; measured by electricity, 373; non-conductors, 186-188, 190; treatment of steel, 167; withstood by Jena glass, 183.
• Heater, Gold’s electric, 87.
• Heating and power production united, 471; ventilating, and Sturtevant methods, 380, 472; coils, 86; district, by steam, 448; by water, Morris Building Co., Brooklyn, 485.
• Hefner unit of illumination, 226.
• Helium, density, 213; in sun, in minerals, may be a constituent of chemical elements, 202.
• Helmholtz ophthalmoscope, 321.
• Herkomer, Hubert, direct reproduction, 342.
• Herschel, resources of, 305.
• Heusler, F., magnetic alloys of non-magnetic elements, 173.
• Hewitt mercury-vapor lamp, 161; Jena glass for, 183.
• Hides prepared for use, 138.
• Hillman, H. W., household uses electricity, 484.
• Hip joint section, 252.
• Holloway, J. F., supports turbine by upward pressure water, 371.
• Holmes, W. H., Art in shell of the Ancient Americans, 116; form and ornament in ceramic art, 111, 115; Pottery of the Ancient Pueblos, 108, 109.
• Holophane globes, 78-81, 229.
• Homestead blowing machinery, 415.
• Hood, ventilating, for alcohol lamp, 158.
• Hooke’s universal joint, 256.
• “Hopes and fears for art,” Wm. Morris, quoted, 114.
• Hopkinson, J., on limits to rules, 383; on mathematical analysis, 384.
• Hornet and moth, resemblances, 288.
• Horse, evolution of, 249.
• Hottentots learn from baboons, 136; antidotes for snake venoms, 296.
• Hough, Walter, acknowledgment to, xxi.
• Houses numbered, 351, 352.
• Howe, truss, 24, 25.
• Howe, H. M., “Iron, steel and other alloys”; “Metallurgy of steel,” 177.
• Howell, Wilson S., maintains uniform voltage, 243.
• Howells, W. D., “Hazard of new fortunes” quoted, 306.
• Hudson, W. H., on folk medicine, 295.
• Hughes, David E., microphone, 147.
• Hull, Gordon F., on pressure of light, 133.
• “Human body,” H. N. Martin, 252.
• Hungarian milling, 321.
• Hussey, Obed, mower, 320.
• Hutton, F. R., on gas engine, 464.
• Huygens employs pendulum, 222.
• Hyatt bearing, 47, 49.
• Hyde, E. P., Bureau of Standards, photometer, 235.
• Hydraulic presses curved, 50; pressure as counterbalance, 371.
• Hydrogen in thermometry, 225.
• I-beam developed from joist, 10.
• Ice-lens focusses solar rays, 5.
• Identifying faculty, 360.
• Idiom of material, 111.
• Ignorance and discovery, 294; Bessemer’s golden, 403.
• Illumination, Art of, Louis Bell, 229, foot-note.
• Imagination in invention, 309; Faraday’s powers of, 392; Tyndall on, 361.
• Imitation of Nature, 249.
• Indian gluttony, a cause of, 137.
• Indicative plants, 296.
• Individuality of matter, 358.
• Indurated fibre, 322.
• Ingalls Building, Cincinnati, concrete, 438, 440.
• Ingersoll coal cutter, 418.
• Ingersoll, Ernest, acknowledgment to, xxi; on debt of birds to feathers, 250.
• Initiation in chemistry, 337; in photography, 338.
• Injector, Giffard, 347.
• Inking rollers, 40.
• Inks tested with Uviol lamp, 183.
• Insanity, its revelations, 379.
• Insects trapped by sundew, 281.
• Instruments aiding observation, 356; advance astronomy, 230.
• Interborough power-house, roof truss, 21; tests coal, 241; exterior facing 450; interior facing 452; automatic machinery, 447.
• Interchangeability old and new, 238, 230.
• Interest as prime factor in discovery, 306.
• Interference water-waves, 214; light, 215, 216; discovered by Thomas Young, 366.
• Interferometer, 214-217.
• Introductory, 1.
• Invar, 169; used for time-pieces, 223.
• Invention at first slow, 115; Bessemer on nursing and tending an, 407; organized in America, 414, in Germany, 275; prerequisites, 271; social aspects of, 478; literature of, 486.
• Inventions, origin of, O. T. Mason, 107.
• Inventors improve their work in act of construction, 300.
• Inverted arc-light, 75, 76, 381.
• Iron, inflammable variety of, 151; crystallization, J. W. Mellor, 177; as electrical conductor, as affected by admixtures, 173; its three forms, 151; foundries, list, foot 178; history manufacture, J. M. Swank, 178; metallurgy, A. H. Sexton, 178; T. Turner, 179; works, directory, J. M. Swank, 178; steel and other alloys, H. M. Howe, 177; strength of wrought, 20, 21; and steel manufacture, H. H. Campbell, 177; Sir I. L. Bell, 177; Institute Journal, 179.
• Isolated plants, 473-74; serving neighborhood, 475, 481.
• Jackson, Robert T., observation leaves, 281.
• James, William, on discovery, 359; on limits to rules, 382.
• Japanese architecture, Ralph Adams Cram, 114, foot-note; pottery, 113, 288; wood-work, 113.
• Jena glass, 180; first experiments, 181; refraction and dispersion, 181; transparent, 182; in photography, 182, 183; in microscopy, 182; annealing, 182; in thermometry, 182, 225; resists heat and corrosion, 183; transmits ultra-violet rays, 183; lenses, 255.
• Jenner, Dr., vaccination, 295.
• Jetties, Mississippi, J. B. Eads, 283.
• Jevons, W. S., “Principles of Science,” 229; on discovery, 364.
• Joint, Hooke’s universal, 256.
• Joist, more rigid than plank, 7; and plank bent double, 7.
• Joule, J. P., discovery of thermo-dynamic law, 212.
• Journal Iron and Steel Institute, 179.
• Journals, hollow, 40.
• Judgment, William James on, 382; Alex. Bain on, 385; moves to new fields, 385; in ship design, 63.
• Jupiter, size of, 121; fifth satellite discovered by E. E. Barnard, 285.
• Justifying wedges, 323-325.
• Kaiser Wilhelm II., steamer, 59, 60.
• Kelp absorbs from sea iodine and bromine, 296.
• Kelvin, Lord, estimates size molecule, 131; defines entrance and run of ships, 53; on measurement, 211.
• Kennedy, A. B. W., on simplification, 341; on economy in machines, 383.
• Kepler as discoverer, 270, 305; his law, 388.
• Kersten, Frederick, separates diamonds from other stones, 150.
• Kidneys, disease of, affects vision, 379.
• Kingpost truss, 18.
• Kites improved by perforation, 292.
• Knitting faculty, 359.
• Knives, 90.
• Knowledge necessary to inventor and discoverer, 267; Bessemer’s view, 408.
• Koebele, Albert, saves orange groves, 282.
• Krakatoa volcano, 125.
• Krypton, 213.
• Kuzel, Hans, tungsten electric lamp, 160.
• Labor, division of, modified, 480; saving devices in farming, 478.
• Lachine bridge, 32.
• Lalance & Grosjean, pressed ware, 185.
• Lamp and reflector a unit, 75; giving heat and light, 343; arc, 160; incandescent, as standard, 227.
• Langley, S. P., bolometer, 225; churns air in telescope, 348; mechanical flight, 262; on Cuban firefly, 263.
• Larned, J. N., editor “Literature of American History,” xxii.
• Lathe, 95-98; cutters, 90; rotary mandrel, 48; tool, 93, 94.
• Lattice trusses, where best, 35; showing rivets, 36.
• Lavoisier balance, 209.
• Law as binding thread, 134.
• Lead, solid, dissolves solid gold, 201; pipe made by pressure, 325.
• Leaves observed by R. T. Jackson, 281.
• Le Chatelier, electrical thermometer, 226.
• Lenard, Philipp, cathode rays, 198.
• Lenoir gas engine, 458.
• Lens, Dollond, 254, 255; Fresnel, 72, 74; grinding, 83, 84.
• Le Vaillant on food eaten by monkeys, 259.
• Leverrier, Urbain, discovers Neptune, 378.
• Levers and limbs, 256.
• Libraries, public, technological departments, 486-87.
• Light causes sound, 393; 398-400; colors investigated by spectrometer, 228; deflects dust, 133; explodes a compound, 337; interference of, 215, 216; discovered by Young, 366; measurement of, 226, 228; polarized, reveals strains, rock structure, measures sugar, 327; pressure of, 133; reflection, 229, total, 76-82; sources of, 154; ultra-violet, Jena glass utilizes, 182; violet and yellow, photographic effects, 338; well transmitted by Jena glass, 182; what it should cost in mechanical energy, 158; arc, inverted, 75, 76, 381; Drummond lime, 155; wave as unit of length, 217.
• Lighthouse, curves for base, 51; has form of tree, 250.
• Lighting, electric, 158-162; General Electric Co.‘s researches, 416.
• Lightning paths, 245; protection through warm air and smoke, 294.
• Lime-light, Drummond, 155.
• Limits to rules, 382.
• Link Belt Machinery Co.‘s Shop, Chicago, 380.
• Link belting, 69.
• Linotype, Mergenthaler, 323.
• Literature of invention and discovery, 486.
• Lithography, aluminium for, 144.
• Liver as sugar-maker, 262.
• Lobster’s tail, hint from, 259.
• Lock-woven wire fabric, 439.
• Locking bar water-pipe, Ferguson, 45.
• Lockyer, Sir Norman, on stellar evolution, 204.
• Locomotive with cog wheels, 345, 346; gas engine for, 466; high pressure steam for, studied with aid from Carnegie Institution, 277; increased in weight, 15; tests, Pennsylvania R. R. Co., 241, foot-note; with and without superheaters, 451; General Electric Co., 128, 129, 415, 476, facing 476.
• Lodge, Sir Oliver J., on bad electrical contact, 146.
• Looms, Northrup, 330.
• Lubricating oil reservoirs, 447.
• Lumber, how dried, 130; for furniture bent and seasoned at once, 343.
• Lungs, separation of oxygen from air by, 261.
• “Lusitania,” steamer, 128.
• Luxfer prism, 74.
• Mach, Ernst, on accidental discovery, 291.
• Machine tools, 94-101.
• Machines code their operations, 317.
• Madison Square Garden curve, 50.
• Magazine-rifle tubes, 40.
• Magnet in steel-making, 168; curved, 50.
• Magnets in astatic needle, 149.
• Magnetism measured, Bureau of Standards, 235.
• Magnetite arc-lamp, 161.
• Magnetization leaves traces, 192; J. Hopkinson on, 384.
• Magneto-electricity discovered by Faraday, 373.
• Malaria and mosquitos, 295.
• Mandolin pressed in aluminium, 185.
• Manganese steel, non-magnetic and tough, 171.
• Manganin, Weston’s, 234.
• Mangle rolls, 40.
• Mangling and drying at once, 343.
• Mann, C. R., acknowledgment to, xxi.
• Mantle, gas, Welsbach, 155-59.
• Manual training, 309, 310.
• Manufacturing, tendencies in, E. Atkinson, 480, foot-note.
• Marble is plastic, 152; deformed by pressure, 195, 196.
• Mars satellites discovered by Asaph Hall, 286.
• Martin, H. N., “Human Body,” 252.
• Mason, Otis T., “Basket work of N. A. aborigines,” 112; “Indian Basketry,” foot-note, 110, 142; on British Columbian basketry, 110; on Pai Utes’ water-bottles, 111; “Origin of inventions,” “Woman’s share in primitive culture,” 107.
• Material, idiom of, 111.
• Mathematical analysis, J. Hopkinson on, 384.
• Matter, constitution of, 358; impressed by its history, 190.
• Maudslay as a mechanic, 299; as a trainer of other inventors, 300; sense of form, 308; slide-rest, 94, 96.
• “Mauretania,” steamer, 128.
• Maxwell, James Clerk, on Faraday’s lines of force, 392; on cross-fertilization of sciences, 275.
• Mayer, A. M., magnetic experiments, 192, 193.
• Measurement, 208-244; discussed by A. B. W. Kennedy, 383; its beginnings, 208; irregular areas, 347; light-wave as unit of, 217; refraction, 344; standards sought, 210.
• Mechanical draft, 380, 448, 472.
• Medicine, original research in, 269, 272, 273.
• Mellor, J. W., “Crystallization iron and steel,” 178.
• Memorial Bridge, Washington, D. C., 444.
• Memory for observations, 293.
• Mendenhall, T. C., designs pendulum, 224.
• Mercer, John, and mercerization, 138.
• Mercury thermometer, 225; vapor lamp, Hewitt, 161.
• Mergenthaler linotype, 323.
• Metal pressing, Bliss, 184-186.
• Metallography, study of, J. W. Mellor, 177.
• Metallurgical machinery, automatic, 332.
• Metallurgie, Revue de, 179.
• Metcalf, Wm., axe and its story, 377.
• Meteorology, 338, 339.
• Metre, origin, 210.
• Metric system, 210, 211.
• Michelson, A. A., portrait, facing 214; interferometer, 214-217.
• Micrometer caliper, 236.
• Microphone, origin of, 147.
• Microscopy, Jena glass for, 182.
• Mile, nautical, 211.
• Mill, John Stuart, four methods experimental inquiry, 360; on sound observation, 279.
• Miller, Hugh, “My schools and schoolmasters” quoted, 307.
• Milling cutters, 48, 98, 100, 101; tell story, 377; machine, 98, 100, likely to gain on planer, 173, cuts gears, 67.
• Mining in Hartz mountains, 411; placer, 124; separations in, 126.
• Mississippi mud, 123; jetties, J. B. Eads, 283.
• Mitchell, Walter A., acknowledgment to, xxi.
• Models and law of size, 126, 127.
• Modernizing a plant, 243.
• Moissan, Henri, artificial diamonds, 265.
• Moisture necessary for combustion in oxygen, 338, 374.
• Molding clay, 102, 103.
• Molds, reinforced concrete, 438, 440.
• Molecule, size, 130; as reservoir energy, 131.
• Molitor, D. A., esthetic design of bridges, 38, foot-note.
• Molybdenum in high-speed tool steel, 172.
• Mond gas, 461.
• Monier, Joseph, reinforces concrete, 435; netting, 437.
• Monitor, Ericsson’s, 97, 98.
• Montreal, Notre Dame de Bonsecours, 118.
• Moon, size of, 121; motions observed by Chaldeans, 293.
• Moor grass, section, 251.
• Morris Building Co., Brooklyn, hot-water service, 485.
• Morris, William, “Hopes and fears for art” quoted, 114.
• Morse, Edward S., naturalist, archaeological observer, 287, 288; on Japanese pottery, 113.
• Morse signals on Burke system, 354.
• Mortar, Roman, 139.
• Mosquitos and malaria, 295.
• Moth and hornet, resemblances, 288.
• Motion may explain properties, 207.
• Motive power produced with new economy, 446-477; of human body, 250.
• Moulton, Sir John Fletcher, on coding in invention, 317.
• Mower, Obed Hussey, 320.
• Multiple drills, saws, punches, 290.
• Murdock, Wm., introduces gas-lighting, 154, 280.
• Murphy machine shears timber, 322.
• Muscles, fibrils of, 258.
• Mushet, R. F., high-speed tool steel, 171.
• Musical instruments and their prototypes, 257.
• Narwhal tusk, 259.
• Nasmyth, Alexander, invented bow string bridge, 308.
• Nasmyth, James, trained by Maudslay, 300; on drawing, 308.
• National Museum, Washington, aboriginal art, 106.
• Nature a drama, not a tableau, 355; as teacher, 245-266; unity of, 357.
• Nebular theory illustrated, 149.
• Needle for sewing-machine, 379.
• Neon, 213.
• Neptune, discovery of, 214, 378.
• Newark Public Library, 487.
• Newcomb, Simon, on original research, 269; on analysis and generalization, 277.
• Newton as a boy tireless in construction, 301; makes a sundial and a telescope, measures force of storm, 302; corpuscular theory of light, 203; discovery of law of gravitation, 211, 387; fails to observe black lines of solar spectrum, 284; on achromatism, 254; rings, 237, 238.
• New Amsterdam Theater, New York, 119, facing 118.
• New York Central R. R. Line, its course, 246.
• New York Subway, reinforced concrete, 443.
• Niagara Falls retiring, 123; turbines at, 70, 371.
• Nichols, Ernest F., on pressure of light, 133; sensitive thermometer, 226.
• Nickel, how made malleable, 176.
• Nickel-steel, 166, 167; of like expansibility with glass when heated, 170; which shrinks when heated, 170.
• Nickelin, Weston’s, 234.
• Nicolaysen, N., on Viking ship, 57.
• Nitro-glycerine, 409, 410.
• Nobel, Alfred, improves nitro-glycerine, 410; invents dynamite, 410; profits by accidental use of collodion, 411; invents smokeless powder, 412; character and benefactions, 413.
• Noise desirable as warning, 148.
• Non-conductors heat, 186-188, 190, 374, 473.
• Northrop looms, 330.
• Norton, Prof. C. L., on window glass, 73; on corrosion steel in concrete, 441.
• Notre Dame de Bonsecours, Montreal, 118.
• Norwegian cooking box, 189, 374.
• Notes, cards for, 350.
• Numbering houses and rooms, 351, 352.
• Observation, 279-298; a matter of mind as well as of eye, 279; now fuller than formerly, 152; Kersten’s leads to mechanical separation of diamonds from other stones, 150; Mercer’s, leads to mercerization, 138.
• Odor, distressing, is useful, 146.
• Oersted’s discovery of electro-magnetism, 230, 290, 373.
• Office-buildings, New York, 115.
• Oil engines, 466.
• Oils, Bessemer improves drying of, 409.
• Omission gainful, 345, 346.
• Open hearth process, 164.
• Ophthalmoscope, Helmholtz, 321, 379.
• Orange groves saved from fluted scale insect, 281.
• Ordway, J. M., on non-conductors heat, 187.
• Ore stamps, Edwin Reynolds, 344.
• Organic and inorganic series united, 357.
• Organized invention, 414.
• Origin of inventions, O. T. Mason, 107.
• Original research, 267-278.
• Osmium electric lamp, 160.
• Ostwald, W., on original research in Germany, 275.
• Otto gas engine, 463.
• Oven and its converse, the safe, 374.
• Oxygen, dry does not support combustion, 374; from air, 261.
• Pace as measure, 209.
• Packages and wrappings, 130.
• Pai Utes’ water bottles, 111.
• Painting by immersion, 348; compressed air for, 422, 423.
• Paley on proof, 359.
• Palladio trusses, 22.
• Panel of bridge, 23.
• Paper in continuous rolls, 346; from wood suggested by wasp nest, 261; making, 322; steam cylinders in, 343; toughened, 139; white, as reflector, 76.
• Paraffine is plastic, 195.
• Parchment, vegetable, 139.
• Parsons, Charles A., air compressor, 372; steam turbine, 453-456, performances, 455, on “Turbinia” and other vessels, 455, 456.
• Pascal, powers of, 270.
• Pasteur’s researches, 273.
• Paths of least resistance, 245; directive, 332.
• Paunch copied in pottery, 115, 116.
• Pavements, concrete, 430.
• Peabody, Cecil H., on ship models, 54.
• Pearlite, 164, facing 164.
• Pearson, Karl, on original research, 277.
• Pease, Edson L., acknowledgment to, xxi.
• Peck, Ashley P., acknowledgment to, xxi.
• Peckham, G. W. and E. G., “Wasps solitary and social,” 260.
• Pelton wheel, 71, 332.
• Pendulum, 222; invar for, 170; compensating, 148; measures gravity, 224.
• Pennsylvania R. R. Co., testing laboratory; “Locomotive tests and exhibits,” 241.
• Pentane in thermometry, 225; in Harcourt lamp, 226.
• Pepsine, 295.
• Perch, Sacramento, totally reflected in tank, 77.
• Perforated sails for ships, 291.
• Phonograph, how Edison invented, 310; its latest form, 312; its directness, 343; sapphire for stylus, 153.
• Phosphorescence, 152; a phase of radio-activity, 199.
• Photographic action of radio-active substances, 199.
• Photography, Wollaston on threshold of, 284; discovery of, Daguerre, 304, 305; aids astronomer, 356; effects violet and yellow rays, 338; Jena glass in, 182, 183; reproduces books, 324; silver compounds, 152.
• Photometer, Bunsen’s, 227; Matthews‘, 228; Hyde’s, 235; Faraday’s simple, 391.
• Phrenology absurd, 359.
• Pianola, 333-335.
• Pianos shipped in refrigerator cars, 349.
• Picard measures the earth, 388.
• Pickering, E. C., on astronomical co-operation, 278.
• Picturing power, 307, 309.
• Piling, reinforced concrete, 438.
• Pin-connected trusses, where best, 35; bridges, 36, 37.
• Pine tree growing by itself, 248.
• Pipe, gallows, 86; grass, section, 251.
• Pitchblende, a source of radium, 199.
• Pitcher, pressed seamless, 185.
• Placer mining, 124.
• Planers, 97, 98, 99.
• Planets differ in size, 120.
• Planimeter, 347.
• Plants, indicative, 296.
• Plaster ornaments, how made, 325.
• Plastic arts, form in, 103.
• Plate girders, where best, 35.
• Plateau’s experiment, 148.
• Platinum as lamp filament, 158.
• Plauen, Germany, bridge, 42, 43.
• Plow, its beginnings, 380; works well because simple, 340.
• Plowshare improved, 91; of two kinds of steel, 167; self-sharpening, 258; removable, 239.
• Plucker tubes, 198.
• Plug and ring, 237.
• Pneumatic hammer, in steel tubing, 41; tools, 40, 41; tube cleared, 321.
• Poetsch, H., freezes sand to stop influx water, 326.
• Polarized light reveals strains, rock structure, measures sugar, 327.
• Pomo basket, 109.
• Porro prisms, 81, 82.
• Portland cement, 430.
• Post of bridge, 23.
• Post office and branches, 256; Chicago, gravity as motor in, 322.
• Potential energy, 358.
• Potter, Humphrey, invents self-acting valve-motion, 329.
• Pottery forms, 112; Japanese, 113, 288; of the Ancient Pueblos, W. H. Holmes, 108, 109; origin of white ware, 290.
• Poulsen, Valdemar, telegraphone, 313.
• Powder, Nobel’s smokeless, 412.
• Pratt Institute Library, Brooklyn, 487.
• Pratt truss, 24, 25.
• Premium plans of wages, 244.
• Press, perfecting, 48; Bliss, work, 184-186; forming die, 184.
• Pressing, 103, 184-186.
• Pressure, extreme, its effects, 152; shaping plaster, soap, clay, lead, 325.
• Priestley on observation, 293.
• Primrose, mutations of, 276.
• “Principles of Science.” W. S. Jevons, 229.
• Prism, Porro, 81, 82; total reflection, 77, 78, 81, 82.
• Prismatic glass, 73, 74.
• Producer gas, 459; advantageous, F. W. Harbord, 476; Dowson, for lighting, 157.
• Projectiles, forms, 65.
• Proof of theories, 358.
• Propeller, 69; improved by accidental break, 291.
• Properties, 135-207; all, probably exist in all matter, 152, 190, 202, 393; may be due to motion, 207, 357; modified, 137; produced as needed, 152; family ties, 188; Faraday on changes in, 206; may change in time, 195; vary in effect with rapid or slow action, 195.
• Protective resemblances, 288.
• Providence Public Library, 487.
• Prowse, Geo. R., acknowledgment to, xxi.
• Ptolemy, observations, 229; astrolabe, 230.
• Public libraries, technological departments, 486.
• Pugh Power Building, Cincinnati, concrete, 439.
• Pump resembles garden squirt, 371; screw, Edwin Reynolds, 70; compressed air for, 421, 422; Worthington, 70, 371.
• Punches, multiple, 290.
• Pupin, Michael I., telephonic researches, 366-369.
• Puzzuoli ashes for hydraulic cement, 429.
• Pye-Smith, Dr., on knowledge, 267; on disinterested quests, 272; on verification, 358.
• Quantitative inquiry, 209.
• Quarrying, compressed air in, 427.
• Queen-post truss, 21; two, trusses form a bridge, 22.
• Radiation may be material or ethereal, 203.
• Radiator tubing, 87.
• Radio-activity, 197-207; and alchemy, 203; may explain heat of earth and sun, evolution of chemical elements, 204; compared with common evaporation, 200.
• Radium discovered by Pierre Curie and wife, 199; investigated by Ernest Rutherford, 199; where found, 200; heat of, probable life, fund of energy, 202; warmer than surroundings, 132.
• Railroad, best lines for, 246; bridges, 23; carriages, European, 118, 342; crossings, frogs, switches of manganese steel, 171; economies due to improved rails, 15; engineers observe buffalo trails, 259; Russian, 247; track cleared by steam, 124, dipping downward, 66, 67; trains, fast, Zossen, 66.
• Rails for railroads, 13; Dudley’s forms, 16; steel for, 169.
• Raiment, how chosen, 135.
• Rammer, compressed air for, 420.
• Ramsay, Sir William, “Gases of the atmosphere,” 214, foot-note.
• Range, steel, pressed, 185, 186.
• Ransome, E. L., designer in reinforced concrete, 436, 439.
• Ratchet bit brace, 90.
• Rayleigh, Lord, discovers argon, 213; on electrical advances, 274; theory of sound, 366.
• Raymond, R. W., on indicative plants, 296.
• Reaping machine, Obed Hussey, 320; must be carefully used, 341.
• Reeds, Egyptian, as drills, 93.
• Reflection, 75, 76; total, 76-82.
• Refraction measured, 344.
• Refrigerator cars for shipping pianos, 349.
• Reinforced concrete. See Concrete.
• Removable parts of tools, 239.
• Research, original, 267-278.
• Resemblances, protective, 288.
• Reservoir, reinforced concrete, 442.
• Residual phenomena, 214.
• Resistance ships, 52, 53, 277; canal boat, 282.
• Resources, material, as affecting invention, 106.
• Responsiveness in plants, 248.
• Reuleaux, F., on seamless boilers, 46; on minimum number parts in machine, 341.
• Reversibility, electrical, 373.
• Revue de Metallurgie, 179.
• Reymond, Dubois, investigates muscle and nerve, 272.
• Reynolds, Edwin, screw pump, 70; ore-stamps, 344.
• Reynolds, Osborne, on engineering problems, 274.
• Rheostat, 316.
• Ribbed glass, 73, 74.
• Rice, H. H., on concrete blocks, 433-435.
• Rifle-making, tendency of drills, 282.
• Rifling of fire-arms, 65.
• Rigidity due to motion, 358.
• Riley, C. V., saves orange groves, 281.
• Ring drills, 91-93.
• Riveting in bridges, 36, 37; machine, Fairbairn, 370.
• Roads, best lines for, 246; Roman, 410.
• Roberts-Austen, experiments with alloys, preparing steel dies, 175; interpenetration of metals, 201.
• Robins conveying belt, 68.
• Rock structure, polarized light reveals, 327; dissolved with acid, 347.
• Roller bearings, 47, 49; for bridges, 38.
• Rolls for steel, 104.
• Roman cement, 429; mortar, 139; roads, 410.
• Röntgen, C. W., X-rays, 108.
• Roof truss, Interborough Co., N. Y., 21.
• Roofs in France and Canada, 118, 119.
• “Roosevelt,” Arctic ship, 19, 20.
• Rope for transmission power, 347.
• Rose, Joshua, on lathe tools, 94.
• Ross, Dr. Donald, proves malaria due to mosquitos, 295.
• Rowland, H. A., fond of experiment from childhood, 303.
• Royal Bank of Canada, Havana, facing 438.
• Royal Institution, London, founded by Count Rumford, 365.
• Rubber may rebound from a wall or pierce it, 196; cylinders, hollow and solid, 40; vulcanization, C. Goodyear, 289.
• Rudders, Chinese, with apertures, 292.
• Rules have limits, 382; that work both ways, 369-379.
• Rumford, Count, founds Royal Institution, 365; proves heat to be motion, 206.
• Run of ships, 53.
• Rupture of metal, how avoidable, 333.
• Rutherford, Ernest, portrait facing 202; researches in radium, 199; in thorium; opinion with regard to helium, 202; spontaneous transformation of matter, 203. “Radio-activity,” 203.
• Sacramento perch totally reflected in tank, 77.
• Safe and its converse, the oven, 374.
• Sailing vessel forms, 55.
• Sails perforated, 291.
• St. Louis bridge, 31, 41; why in three spans, 127; recent architecture, 112.
• St. Remy, Church of, 43.
• Salt preserves food, 138.
• Sampler, 114, 115.
• San Francisco fire, reinforced concrete in, 440.
• Sand blast, 124, 424, 425; polishes flints, 424; sifter, compressed air for, 420; wind blown, 124.
• Sandstone for buildings, 139.
• Sapphire for phonographic stylus, 153.
• Saunders channeling machine, 342.
• Saunders, W. L., on introduction air tools, 419.
• Saw carriage directly attached, 342; circular, strengthened, 254; gang, 290.
• Saws, multiple, 290.
• Saxonville, Mass., Pipe-arch bridge, 41, 42.
• Schmidt superheater, 451.
• Schott, Otto, Jena glass, 181.
• Schuckers, J. W., justifying wedges, 324, 325.
• Schumann’s Traumerei, 333.
• Screw as derived from narwhal tusk, 259; production of, 236; Rowland’s, 237; propeller, 69; with gimlet point, 90.
• Scroll, free-hand, and development, 111.
• Sculpture, earth, 122; Greek, 114.
• Seamless tubes, 46.
• Sectional bookcases, 351.
• Sedgwick, Adam, fails in observation, 280.
• Selenium, discovery, properties, conducts electricity better in light than in darkness, 394; special treatment, 397; cylinder of, 398.
• Self-hardening steel, 172.
• Separation, how effected, 150.
• Seppings first uses trusses in ships, 19.
• Sewing machine analyzed, 318.
• Sexton, A. Humboldt, Metallurgy iron and steel, 178.
• Shades for light, 229.
• Shaper, 98, 99.
• Shearing stresses, 6.
• Shears for metal and timber, 322.
• Shell, Art in, W. H. Holmes, 116; vessel and clay derivative, 115, 116; making, Bliss, 184.
• Ship, 52-61; big, advantages, 127, 128; Clipper, 57; cross-sections, 63; design, judgment in, 63; gas engines for, 465; perforated sails for, 291; resistances, 52, 53; studies resistance and propulsion, Carnegie Institution, 277; Viking, 55, 56; planning ship-yard, 322.
• Shops, small, 480.
• Siemens, Sir William, open hearth process, 164.
• Signals, Westinghouse, 428.
• Silk, artificial, 261.
• Silo, concrete, 430, 431.
• Silt removed in stream, 124.
• Silver compounds sensitive to light, 152.
• Simplification, 340-354; undue, 383.
• Size, 120-134; in glass-making: materials should be pulverized, 407.
• Skill, manual, passes from old tasks to new, 386.
• Skin scraper, Eskimo, 91.
• Skins prepared for use, 138.
• Slags utilized, 150.
• Slide for timber, cycloidal, 341.
• Slide-rest, 94, 96.
• Smallpox prevented by cowpox, 295.
• Smeaton, James, discovers natural cement, 430.
• Smillie, Geo. F. C., acknowledgment to, xxi.
• Smith, Francis P., propeller, 291.
• Smith, Oberlin, on machine design, 172.
• Smoke abated or not produced, 450; preserves food, 137; protects vegetation, 146.
• Smoke-jack, 449.
• Smokeless powder, Nobel’s, 412.
• Smyth, William H., on invention, 271.
• Snails, land, observed by E. S. Morse, 287.
• Snake venoms, antidotes for, 296; studied Carnegie Institution, 277.
• Snow, Walter B., “Steam boiler practice,” 450.
• Soap, shaping by pressure, 325.
• Social aspects of invention, 478.
• Sociological observations, Karl Pearson on, 277.
• Soda formerly wasted now used, 150.
• Soil tillage, 124.
• Solenoid, 316.
• Solid contents ascertained, 343, 344.
• Solids and surfaces, law of, 122.
• Sound caused by light, 393, 398-400; enables a pneumatic tube to be cleared, 321; interference of, 366; mill, Dvorak, 132.
• Sparks, electrical, useful, 147.
• Sparrows feeding, 136.
• Specialization, Thomas Young on, 365; and group attack, 416.
• Specific gravity learned, 344.
• Spectacles, bi-focal, 85.
• Spectrometer investigates colors of light, 228.
• Spectroscope, Fraunhofer invents, 284; utilized, 218.
• Spinning, 126; jenny, Hargreaves invents, 290.
• Spiral grooves in fire-arms, 65; steel tube, 42.
• Spring, W., makes alloys by pressure, 201.
• Square root extractor, 376, 377.
• Squirt, garden, 371.
• Staircases, curved joints for, 49.
• Stamping, 103; machines curved, 50.
• Standard sizes in manufacturing, 239; in power plant, 385; of measurement sought, 210; electrical measurement, 239; Bureau of, 234-236; two varying yards, 195.
• Stars, fixed, observation of, 213; double, measurements, Sir David Gill, 286; observed by E. E. Barnard and S. W. Burnham, 285, 286.
• Stas, elimination of sodium, 364.
• Steam, Watt’s study of, 361; and gas engines compared, 466; engine, automatic auxiliaries, 329; condensers, 87; Weighton’s, 452; losses, H. G. Stott, 469-71; performances, 448, 451; resembles garden squirt, 372; multiple cylinders, 372; Watt’s first, 101; Allis-Chalmers, facing 448, facing 452; hammer directly attached, 342; high-pressure, for locomotives, studied Carnegie Institution, 277; turbine, 452-456, Westinghouse-Parsons, facing 454, costly experiments, 414, should be joined to steam engine, H. G. Stott, 470; and both to gas engines, 471.
• Steamer forms, 55; for cargo-carrying, 59, 61.
• Steatite fibres, 235.
• Steel, 163-179; annealing, 168, J. V. Woodworth, 179; barrel pressed, 185; Bessemer’s story of his process, 403-407; corrodibility reduced, 167; crystallization, J. W. Mellor, 178; dies, 175, effects of use, 358; drills, 418; electric and magnetic qualities, 151; examined microscopically, 163; expanded, 437, 438; for biggest structures, 128; for mechanical flight, 129; forging, J. V. Woodworth, 179; hardening, J. V. Woodworth, 179; heat treatment, 167, study aided by Carnegie Institution, 277; high-speed tool, 171; in architecture, 119; invar, 169; iron and other alloys, H. M. Howe, 177; manganese, non-magnetic and tough, 171; manufacture of, H. H. Campbell, 177; manufacture iron and, Sir I. L. Bell, 177; mechanical treatment, F. W. Hall (See under Harbord), 177; Metallurgy, F. W. Harbord, H. M. Howe, 177, A. H. Sexton, 178, T. Turner, 179; pressed, car, 186; rails, 169, wear at Crewe, 406; range pressed, 185, 186; rolls, 104; strength of, 20, J. Hopkinson on, 384; tempering, 168, J. V. Woodworth on, 179; to order, 166; tube, spiral, 42; tubing, uses for, 40, 41; under microscope, facing 164; J. W. Mellor, 178; used unduly thick, 117; wire, strength, 32; works directory, J. M. Swank, 178.
• Steinheil’s ground wire in telegraphy, 346.
• Stephenson, George, as a mechanic, 299; railroad lines, 246.
• Stewart, Balfour, on meteorology, 338.
• Stoker, automatic, 330, 450; underfeed, 380.
• Stolp radiator, 87.
• Stone outlines, 112; as chosen by Indians, 143; broken by frost, 123.
• Stop motion, 330.
• Storage cell, Edison, 374.
• Stott, Henry G., acknowledgment to, xxi; on power plant economies, 469-71.
• Stoughton, Bradley, acknowledgment to, 173; list of books on iron and steel chosen and annotated by, 176.
• Stoves for heating, 86; Canadian box and dumb, 86.
• Strains in bridges studied, 25; revealed by polarized light, 327.
• Strap rail and stringer, 13.
• Stream, model, by James Thomson, 283.
• Stresses tested, 192; recurrent, 191.
• Strowger, Almon, inventor automatic telephone, 337.
• Strut of bridge, 23.
• Sturgis, Russell, on modern architecture, 119.
• Sturtevant ventilating and heating apparatus, 380, 472.
• Sugar, polarized light measures, 327.
• Sugar-cane mill, Bessemer’s, 402.
• Sulky in steel tubing, 41.
• Sulphate of ammonia from Mond plant, 461.
• Sun, size of, 121.
• Sundew traps insects, 281.
• Superheaters, 450, 451.
• Surfaces and solids, law of, 122.
• Surveying, invar wires for, 170.
• Suspension bridges, 32; where best, 35.
• Swallow, bank, lesson from, 297.
• Swank, J. M., Directory Iron and steel works; History manufacture iron, 178.
• Tainter, Sumner, aids Professor A. G. Bell in perfecting photophone, 393.
• Talking Machine, Faber, 343.
• Tamarac copper mine, stamp, 344, 345.
• Tamping, compressed air for, 420.
• Tanks, experimental, for ship models, 54, 55; U. S. Navy, facing 54; reinforced concrete, 441.
• Tantalum electric lamp, 159, 160.
• Taylor gas producer, 460.
• Team work in research and invention, 415.
• Telautograph, Gray, 313, facing 318.
• Telegraphic registers, Edison’s, 310.
• Telegraphone, Poulsen, 313, facing 314.
• Telegraphy, ground wire in, 346; codes in, 352-354.
• Telephone, Professor Bell’s narrative of invention, 393, foot-note; earnings, 484; as part of photophone, 395; two conductors for, 149; automatic, 335-337; central station, 257; researches, M. I. Pupin, 367-369.
• Telescope, aid from, 356; air churned in, 348.
• Tellurium added to bismuth, 175.
• Tempering steel, 168.
• Tension, 8; members need not be of rigid material, 19.
• Terra cotta, 323.
• Testing apparatus, Emery, 242; Laboratories, Electrical, N. Y., 242; materials, American Society for, 241; International Association for, 241; industrial, increasing in demand, 243.
• Thacher, Edwin, bar, 436; on reinforced concrete bridges, 436, 444.
• Thawing ice by electric heat, 347.
• Theater, New Amsterdam, New York, 119, facing 118.
• Theories, how reached and used, 355-386.
• Thermo-electricity and its converse, 373.
• Thermometer, mercury, 225; Jena glass for, 182.
• Thermometry, interferometer in, 216.
• Thomas, Carl C., “Steam turbines,” 456.
• Thomas, J. J., “Farm Implements” quoted, 340.
• Thompson, Benjamin, founds Royal Institution, 365; proves heat to be motion, 206.
• Thomson, James, models stream, 283.
• Thomson, Joseph J., on electrons, 132; on cathode rays, 198.
• Thorium radio-active, 199; Ernest Rutherford’s researches in, 200; two substances separated from, by Charles Baskerville, 200; in gas mantle, 156, 157.
• Through bridge, 24.
• Thurston, R. H., on inventors of the past, 265; on planning investigation, 270.
• Tie of railroad, 13; bridge, 23.
• Tiffany, George S., improves telautograph, 317.
• Tiles, roofing, studied by E. S. Morse, 288.
• Tilghman, B. C., sandblast, 124, 424.
• Tillage soil, 124.
• Timber, Murphy machine shears, 327; slide, cycloidal, 341.
• Time modifies properties, 138; measurement, 221, 222; service, W. U. Telegraph Co., 330.
• Tool design, 89; materials for, 136; machine, 94-101.
• Tooth of beaver, 258.
• Torpedo-boat destroyer, 62, 64.
• Total reflection, 76-82.
• Towers, Beauchamp, researches on friction, 274.
• Track indicator, Dudley’s, 14.
• Trade, how it began, 219.
• Training, manual, 309, 310.
• Transmission motive power, 347.
• Traumerei, Schumann’s, 333.
• Tray, wooden, and clay derivative, 115, 116.
• Triangle as stable form, 18, 19.
• Triggers, chemical, 337.
• Truss, model of simple, 19; Baltimore, 25; Howe, 24, 25; kingpost, 18; Pratt, 24, 25; queen-post, 21; Palladio, 22.
• Tubes, Mannesmann, 46; for radiators, 87.
• Tungsten in high-speed tool steel, 172; electric lamp, 160.
• Tunnel, bank swallow gives hint for, 297; bored through frozen ground, 326; concrete, 430.
• Turbine wheels, 69, 70; Francis vertical, 446; reversed as pump, 371; supported by upward pressure water, 371; steam, reversed as air compressor, 372. (For other entries see under Steam-turbine.)
• Turner, Thomas, Metallurgy iron and steel, 179.
• Turret lathe, 97.
• Twist drills, 93.
• Tyndall, John, on dogmatism, 363; on imagination, 361; on original research, 273; on scientific co-operation, 274; on verification, 362.
• U-bend in pipe, 88.
• Ultra-violet rays, Jena glass utilizes, 182.
• Umstead, C. H., strengthens concrete with crushed stone, 240.
• Uniform voltage economizes lighting current, 243.
• Unit systems, 350, 351.
• United States Geological Survey, coal testing plant, 241, foot-note; Steel Co., as carriers, 415.
• Unity of nature, 357.
• Uranium, radio-active, 199.
• Use creates beauty, 104, 105.
• Uviol lamps, 183.
• Vacuum, James Dewar produces, 327; cleaning method, 423, facing 164.
• Valve-motion, Humphrey Potter’s, 329.
• Valves of veins, 251, 252.
• Van Vleck, John, acknowledgment to, xxi.
• Variations seized, 249.
• Vase from tumulus, 116.
• Vegetation, engineering principles in, 247; smoke protects, 146.
• Vehicles, forms, 65.
• Veneer as wall covering, 342.
• Ventilating and heating, Sturtevant methods, 380, 472.
• Verification, Tyndall, 362.
• Vial and bubbles, 127, 128.
• Victoria Bridge, Montreal, 26-28.
• “Victorian” driven by steam turbines, 455.
• Viking ship, 55, 56.
• Vines saved from phylloxera, 289.
• Violet, zinc, 296.
• Violins improve with use, 192.
• Volcanic outbreaks, 245; Krakatoa, 125.
• Voltmeter, Weston’s, 232.
• Volutes in turbines, 69.
• Vulcanite somewhat transparent, 338.
• Wachusett Dam, concrete, 431.
• Wadsworth, F. L. O., improves interferometer, 217.
• Wage-earners, more in manufacturing than formerly, 479.
• Wages, premiums in, 244; American, average in 1900, 486.
• Waidner, Dr., Bureau of Standards, 235.
• Wallace, A. R., facts and arguments, 359.
• Warship curves, 51.
• Wasp nest suggests paper from wood, 261; using pebble as hammer, 260.
• Wastes prevented, 149.
• Watches and watch-making machines, 222.
• Water, angle total reflection, 77, 78; boiling point lowered as atmospheric pressure lessens, 375; courses deepened, 123; current, two modes of measuring, 370; expands in freezing, pressure lowers freezing point, 375; gas, 459; moving, as source of power, 360; pipes gradually joined, 50, reinforced concrete, 442; supply indicated by vegetation, 297; tight basketry, 142, 143; under pressure for power transmission, 348.
• Watson, Egbert P., suggests steel tubing for bridges, 41, 42.
• Watt, James, a mechanic from boyhood, 299, 302; articulated water-pipe, 258; study of steam, 361; first steam engines, 101; on omissions, 346; suggests metric system, 211.
• Wax, shoemaker’s, is plastic, 195.
• Weapons, materials for, 136.
• Weather predictions, 338, 339.
• Weaving, its beginnings, 138; materials, 110.
• Wedge extracts square root, 376-77; justifying, 323-25; front automobile, 66.
• Weighton, R. L., steam condensers, 452.
• Welsbach, Dr. Auer von, portrait, facing 156; gas mantle, 155-59, and Holophane globe, 81; osmium electric lamp, 160.
• Western Union Telegraph Co., time service, 330.
• Westinghouse brakes and signals, 428.
• Weston ammeter, 233; voltmeter, 232; factory, 234, foot-note.
• Wheel, balance, in time-pieces, 222; Earnshaw’s compensated, 223; bicycle, 382; carborundum, 101, 102; emery, 101, 102; flange on, instead of on track, 370; Pelton, 71; spokeless, 66; toothed, 67.
• Whetham, W. C. D., “Recent Development of Physical Science,” 204.
• Whipple bridge, 25.
• White, J. G. & Co., effect economies, 244.
• White ware, origin, 290.
• Whitney, Eli, interchangeability, 239.
• Williamsburg suspension bridge, 32, 33.
• Wind, work of, 124.
• Windmill vanes, 70; and fan blower, 371.
• Wire fabric, lock-woven, 439; shaped by hydraulic pressure, 326; shortened, 81; tempered as drawn, 343.
• Wollaston, observes black lines in spectra, 284; on threshold of photography, 284.
• Wolvin, Augustin B., ore carrier, 69.
• Woman’s share in primitive culture, O. T. Mason, 107.
• Wood, strength of, 21; compressed, 152; borer, compressed air for, 420.
• Wood, Dr. Casey A., on diseases of the eye, 379.
• Wood, R. D. & Co., gas producer, 460, 466.
• Wooden tray and clay derivative, 115, 116.
• Woodward, C. M., on manual training, 309, 310.
• Woodward, R. S., Carnegie Institution for Original Research, 276; portrait, facing 276.
• Wood-work, Japanese, 113.
• Woodworth, J. V., Hardening, tempering, annealing and forging steel, 179; on milling cutters, 377.
• Work from fuel in human body, 263, 264.
• Worthington pump, 70.
• Wrappings of merchandise, 129.
• Writing appliances, 114.
• Wyer, Samuel S., Producer-gas and gas-producers, 462.
• Xenon, 213.
• X-rays examine electric cables, 327; make air electric conductor, 282.
• Yokut basket bowl, 112.
• Young America, clipper ship, 57, 58.
• Young, Thomas, discovers interference light, 366; on discursiveness, 365.
• Zahm, A. F., mechanical flight, 262.
• Zeiss binocular glasses, 81, 82.
• Zinc violet, 296.
• Zirconium for gas mantle, 156.
• Zuni water vessels, 108.