CHAPTER I PUPILS

All great masters have been represented by pupils who have done honour to their teacher and have achieved personal success in a large measure. Mr. Curtiss is no exception to this rule, for he has taught more than a hundred pupils.

There have been representatives of all classes and all nationalities. The list includes all trades and professions, from horse trainers to bankers. And in all these have been pupils from thirteen nationalities including Russians, Germans, French, Canadians, Scotch, Irish, English, Japanese, Indians, Cubans, Mexican, Spaniards, and Greeks.

Instruction has been given in all languages, including the sign language. Some nationalities are naturally a little harder than others to instruct, largely because of national characteristics of thought, and also for the reason that in a southern climate those native to it are often unaccustomed to the rapid action necessary at times in flying.

Negroes have not yet as a class taken to aviation, but there is one Chinaman in California, Tom Gun, who has been successful as an aviator. But conspicuous among the list of pupils is the number of Army and Navy officers of our own, as well as of foreign countries, that have graduated from the Curtiss School.

Hydroaeroplane operation has also been taught to a number of pupils both at Hammondsport, N. Y., and at San Diego, California, where the training camps are located.

The life that the pupils lead at these schools is most interesting and healthful. The students get up early, sometimes at four in the morning, when it is just light enough to see and when the air is usually calm and the best conditions for learning to fly exist. Pupils are outdoors practically all day, flying, or working on the machines when any thing breaks or goes wrong. Many pupils have engaged in exhibition flying after completing their course of instruction, and among the large number of very excellent aviators that have followed in Mr. Curtiss' wing beats (for you can hardly say foot steps) have been some of the foremost aviators in the world and men whose fame and exploits are household words to-day.

A partial list of some of these men at present active in the field is here given:

Chas. F. Willard, Hugh Robinson, Chas. K. Hamilton, J. C. Mars, C. C. Witmer, E. C. St. Henry, Lincoln Beachey, Beckwith Havens, Lieut. T. G. Ellyson, U. S. N.; Capt. P. W. Beck, U. S. A.; Lieut. J. H. Towers, U. S. N.; William Hoff, J. B. McCalley, S. C. Lewis, C. W. Shoemaker, W. B. Atwater, Al. Mayo, Al. J. Engle, J. Lansing Callan, G. E. Underwood, Irah D. Spaulding, C. F. Walsh, Carl T. Sjolander, Fred Hoover, E. C. Malick, Ripley Bowman, T. T. Maroney, C. A. Berlin, H. Park, W. M. Stark, E. H. McMillan, F. J. Terrill, Francis Wildman, F. J. Southard, Lieut. P. A. Dumford, W. B. Hemstrought, Earl Sandt, E. B. Russell, Lieut. J. E. McClaskey, W. W. Vaughn, Barney Moran, M. Kondo, J. G. Kaminski, Mohan Singh, K. Takeishi.

Among those in this list who have done wonderful things, it might be interesting to mention some of the marvellous feats of daring as well as a few of the achievements of Lincoln Beachey, who is credited with being the greatest exhibition aviator in the world.

At the meet in Chicago in the summer of 1911, Beachey flew more miles than any other aviator. He flew all the time and was in the air during all the flying hours in one contest or another. He did all the special tricks in the air that were known, he carried passengers, won speed races, and established a new world's altitude record at 11,642 feet. After flying as high as he could, at Chicago, with a seven gallon tank full of gasoline, Beachey came down and said: "To-morrow I'll go higher." He had a ten gallon tank fitted to his machine, filled it full up to the top, and started right up from where his machine was standing on the ground, so as not to waste a drop of gasoline, and flew up and up until it was completely exhausted and his motor thus compelled to stop, but not until he had set the world's record at 11,642 feet. He deliberately started out on this trip to climb up as long as his fuel would last. He knew his motor would stop and he would have to glide down. It was not an unintended glide but it was the longest glide on record. He brought out all the points and possibilities of his machine; distance, speed, weight-carrying, and altitude. Wilbur Wright said: "Beachey is the most wonderful flyer I ever saw and the greatest aviator of all." Calbraith P. Bodgers said upon his arrival at Los Angeles after flying across the American continent, a distance of over four thousand miles, "Beachey's daring flight down the gorge of Niagara and through the spray of the falls was a greater achievement than mine." Beachey has been remarkably free from serious accidents even though now he pitches straight down from the sky, seeming to fall straight to the earth and just catching his machine up in time to avoid striking the earth.

At Hammondsport on July 29th, 1912, Beachey was trying out a new model military type and he ascended six thousand five hundred feet in fifteen minutes, while he came down in one minute, making one of his perpendicular dives with the engine still. The whistling of the wind through the taut wires of the machine could be heard half a mile away. On this occasion one of the lady visitors to the testing grounds, who had never seen Beachey fly before, thinking that he was falling and would surely strike the ground and be dashed to pieces, fainted. Beachey said, "Flying did not come to me at first but it seemed to come all of a sudden and then it came big." [10]

Once Beachey had to land in a very small place surrounded with trees and the only way he could do it with the fast machine that he was driving was to kill its speed in the air by skimming over the trees, shutting off his motor, and gliding along to the place where he wanted to stop, and then pointing the machine up suddenly, very much as a bird comes to a stop, and then "pancaking" down, as it is called when you come down "kerflop" like a pancake.

Beachey broke a wheel by this performance and he has worried over that little breakage as much as another man would over smashing up a whole machine.

Beachey flew from New York to Philadelphia in company with Eugene Ely and Hugh Robinson in August, 1911, winning the first inter-city race to be held in the United States.

Among the skilled operators of hydroaeroplanes is Mr. Hugh Robinson who flew down the Mississippi River in the spring of 1912, carrying mail and covering the river course between Minneapolis, Minn., and Rock Island, Ill. Mr. Robinson also went to France in May of 1912, and competed in the first contests and races ever held in this new sport at Monte Carlo. Since his return to America, Mr. Robinson has been the instructor in hydroaeroplaning at Hammondsport.

CHAPTER II A DESCRIPTION OF THE CURTISS BIPLANE

No type of aeroplane is more familiar in America than the Curtiss biplane. By long experimentation, this machine has been developed for practical use; and is now used for military purposes in Russia, Japan, Italy, Germany, France, and the United States. The machine is of the general type known as "biplane," in which there are two sets of wings, or surfaces, one being directly above the other. This type of machine seems to be the most favoured by Americans, for it not only allows of a greater spread of lifting surface for a given width of plane than in the monoplane, or single-wing type, but also it is much stronger than other machines of the same weight, as its design permits of a system of bridge-trussing known as the "Pratt Truss." In the Curtiss machine this feature is especially pronounced, because of the greater safety which rigid planes have when compared with the flexible wings.

The woodwork of these aeroplanes is entirely of selected spruce and ash, all the posts, beams, and ribs being laminated. The propeller is a particularly difficult piece of laminated work, being built up of from twelve to eighteen layers of thinly cut wood, while the upright posts of the central section are made up of ash and spruce, the heavier and more flexible wood forming the core. A feature of strength is to be found in the double trussing which is placed in all of the vital parts of the aeroplane, where the greatest strength is required. All this trussing is made with a cable of galvanised steel wire tested to withstand a pulling strain of nearly half a ton.

Transportation and military use have been especially considered in the construction of the planes. The upper and lower planes are made up of interchangeable panels, which are so joined together that the machine is easily assembled and taken apart and may be transported compactly in two flat boxes which scarcely make one full wagon load, as indicated in an illustration in this book.

The wing-panels are made up with a light and strong wooden framework covered with cloth especially made and treated with a rubber coating for the purpose. The curved ribs are laminated also and the panels held together by a system of trussing which gives them great strength. These panels are covered both top and bottom.

Light and strong bamboo rods extend to the front of the main planes, supporting the elevator or forward horizontal surface, which acts as a rudder to steer upward and downward. Similar bamboo rods at the rear support the vertical rudder and rear elevators and stabilising plane. Front and rear elevators work in conjunction with each other so that as the front of the machine is directed up, the rear of the machine is depressed by the two rear elevators, called "flippers" from their resemblance to these appendages of a seal or a turtle, each of which is controlled by an individual set of cables, so that if one should break or get out of order the other may be used independently. The front or rear elevators are sufficient to maintain the fore and aft balance of the machine in flight, so if anything happens to one the other will enable a safe landing to be made. Some aviators take off the front elevating plane entirely, relying solely upon the two rear ones for horizontal control.

The elevators and the vertical rudder are manipulated by a single steering post at the top of which is the steering wheel. Turning the wheel to the right or left steers the aeroplane to the left or to the right as a boat or an automobile is steered, while pushing the wheel forward directs the machine downward and pulling the wheel causes it to rise, a system of control in accord with the natural impulse of the operator.

To maintain the lateral balance of the aeroplane, there are small movable planes, or "ailerons," attached at the ends of the main framework, midway between the upper and lower planes, at the rear. These ailerons are so arranged that the front edge remains in the same position; while one swings upward, the other swings downward, at the back, thus giving an upward pressure of air on the under side of the one, while the other is depressed by the air which strikes it on top. This movement is controlled by a movable back to the aviator's seat or a frame or yoke which fits around the shoulders of the aviator in such a way that he moves the ailerons to the proper position when he leans to the high side of the aeroplane as it tilts and is thus able automatically to correct its balance.

The motors with which the military and cross-country models are equipped are of the eight-cylinder "V-shaped" type, developing sixty and eighty horse-power. The propeller is attached directly to the motor shaft, thus doing away with any necessity of gearing, which consumes power, increases the risk of breakage, and decreases reliability. The speed of the motor is controlled by a throttle opened and closed by a movement of the left foot.

The seat for the aviator is placed well forward of the main planes, giving him a clear view not only ahead, but also straight downward. On the military model, a passenger-seat is provided immediately beside that of the aviator, and a dual system of control makes it possible for either passenger to operate the machine independently of the other.

The aeroplane is mounted upon a three-wheeled chassis with one skid extending from front to rear, the whole landing gear being built strong and rigid to withstand the shock of landing, the most dangerous part of flying.

Elaborate tests are made of the different parts of the machine; the panels forming the surfaces are tested by loading them with gravel until they break and weighing the amount of gravel heaped upon them before they give way. These tests have shown a factor of safety in excess of any strain that could be put on the machine in the air.

The strain on the various wires and cables is also measured, with a special instrument made for that purpose, as seen in an illustration. Every conceivable test has been tried which could give information that would lead to any improvement in strength to withstand strains, in addition to the complete knowledge that has come from actual tests under all conditions in the air, and on the ground itself, by expert flyers who have done almost everything that it is possible to do with the machine as far as trying to find its weak point is concerned. Dives almost straight down with abrupt turns at the end of the drop put many times the ordinary strain on every part. Rough landings also show up any lack of strength or fault in the design of the running gear or frame of the machine, especially since this machine is not provided with any springs or other device for taking up the shock of a bad landing.

CURTISS AEROPLANE PARTS–A COMPLETE LIST [11]

1, Engine Section Panel; 2, Wing Panel; 3, Wing Panel, Sparred Beam; 4-5, Aileron, Right & Left; 6, Tail; 7-8, Flipper, Right and Left; 9, Rudder; 10, Front Control, Elevator only; 11, Hydro Front Control, Elevator only; 12-13, Fin, Top & Bottom; 14-15, Non Skid Surface, Headless & Large.

BAMBOOS

16-17, Front, Upper, Right & Left; 18-19, Front, Lower, Right & Left; 20, Front Cross Tie, Headless; 21-22, Front Bamboo Brace, Right & Left; 23-24, Rear, Upper, Right & Left; 25-26, Rear, Lower, Right & Left; 27, Push Rod Bamboo, 45"; 28-29, Bamboo Post, Short & Long.

30, Full Set Rear Bamboos, Wired Complete; 31, Full Tail Equipment, consisting of Rear Bamboos, Posts, Tail, Rudder and Flippers.

POSTS

32, Wing Panel, 3/8" x 2 3/4" x 54 1/2"; 33, Wing Panel, 3/8" x 2 3/4" x 60"; 34, Engine Section, 1 1/2" x 2 3/4" x 54 1/2"; 35, Engine Section, 1 1/2" x 2 3/4" x 60”.

DIAGONAL ASH BRACES, FROM FRONT WHEEL TO ENGINE BED

36-37, Diagonal Ash Brace, Tinned, Right & Left; 38-39, Diagonal Ash Brace, Left & Right; 40-41, Diagonal Ash Brace, Tinned & Ironed, Left & Right.

DIAGONAL SPRUCE BRACE, FROM FRONT WHEEL TO WING PANEL

42-43, Diagonal Spruce Brace, Left & Right; 44-45, Diagonal Spruce Brace, Ironed, Left and Right; 46, Skid; 47-48, Engine Bed, not Tinned, Right & Left; 49-50, Engine Bed, Tinned, Right & Left.

ENGINE BED POSTS. BRACES AND TUBING BRACES ABOVE LOWER PLANE

51-52, Engine Bed Post, Front, Right & Left; 53-54, Engine Bed Post, Rear, Right & Left; 55-56, Engine Bed Brace, Front, Lower, Right & Left; 57-58, Engine Bed Brace, Rear, Lower, Right & Left; 59-60, Engine Bed Brace, Rear, Upper, Right & Left; 61-62, Engine Bed to Surface, Rear, Upper, Right & Left; 63, A Brace to Surface, Front, Upper; 64, Cross Tie Brace under Upper Surface; 65-66, Aileron Brace, Upper, Right & Left; 67-68, Aileron Brace, Lower, Right & Left; 69-70, Seat Post, Right & Left; 71-72, Carburetor Brace, Right & Left.

CHASSIS BRACES. FORKS AND TUBING UNDER LOWER PLANE

73, Cross Tie Rod, Lower, Under Lower Surface; 74, Long Span Brace, Rear Wheel to Rear Wheel; 75-76, Skid Fork, Right & Left; 77-79, Vertical Fork, Front & Rear, Right & Left; 80-81, Leader Fork, Rear, Right & Left; 82-83, M Brace, Right & Left; 84, Y Brace; 85, V Brace, Front, Skid to Diagonal; 86, V Brace Spreader and Bolt, Front; 87, Brace, Center, Skid to Diagonal; 88, V Brace, Center, Skid to Double Seat; 89, V Brace, Rear, Skid to Diagonal; 90-91, Combination Foot Throttle & Brake, Single & Dual.

92, Brake Shoe; 93, Brake Shoe Hinge; 94, Brake Shoe Lug; 95, Brake Shoe Spring; 96, Steering Column, Single; 97, Steering Wheel, Spider, Fork and Bolt; 98, Steering Wheel, Spider, Fork & Column, Assembled & Wired; 99, Steering Column, Dual; 100, Steering Wheel, Spider, Fork & Bolt, Dual; 101, Steering Wheel, Spider, Fork, Bolt & Column, Assembled & Wired, Dual; 102, Foot Rest; 103, Push Rod, Metal, with Swivel End, Dual.

104, Seat, Single; 105, Seat with Fittings for Shoulder Yoke, Single; 106, Seat, Complete with Shoulder Yoke, Whiffle-tree Case and Whiffle-tree, Single; 107, Seat, Double; 108, Seat with Fittings for Shoulder Yoke, Double; 109, Seat, Complete with Shoulder Yoke, Whiffle-tree Cases and Whiffletree, Double; 110, Seat, Passenger; 111, Seat Supporting Brace, Passenger; 112, Rear Beam Reinforcing Plates.

113, Cable, 1/32"; 114, Cable, 1/16"; 115, Cable, 3/32"; 116, Cable Casing; 117, Short Circuiting Switch; 118, Snaps, 3"; 119, Main Plane Socket; 120, Main Plane Socket, Wired Complete; 121, Main Plane Plate; 122, Aileron End Wire Connection; 123–124, Aileron Cross Wire Clamp & Clip; 125, Aileron L; 126, Aileron Post Lug; 127, Aileron Brace Wire Connection; 128, Aileron Corner Wire Guide; 129, Aileron Corner Pulley, 3"; 129, Aileron Pulley, 3".

131, Bamboo Curved Rudder Wire Guide; 132, Skid Safety Wire Connection; 133, Copper Sleeve; 134, Tin Thimbles; 135, Diagonal Ash Brace Iron; 136, Diagonal Spruce Brace Iron; 137-138, Engine Bed Post Plate & Wire Connection; 139, Engine Bed Bolt; 140, Fin L Irons; 141, Fin Hinge; 142-143, Front Control Bracket & L Iron; 144, Hydro Front Control, Brace Lug; 145-146, Hydro Front Control Supporting Post, L & R; 147-148, Hydro Front Control, Supporting Post Lug, Left & Right; 149-150, Hydro Front Control Push Rod & Bracket; 151-152, Hydro Front Control Post & Diagonal Brace; 153, Hydro Splash Boards.

154-155, Flipper Post & Wedge; 156, Flipper Hinge; 157, Flipper Wire Guide, Straight; 158, Rudder Swivel; 159, Curved Corner Wire Guide; 160, Rudder Lever Clip; 161, Rudder Wire Connection; 162, Rudder Wire Guide, Curved; 163-164, Terminals, Short & Long; 165, Turnbuckles; 166, Wheel, 20" x 4", Complete; 167, Wheel, 20" x 4", Less Tire; 168-169, Wheel, 20" x 2 1/2", Complete & Less Tire; 170, Inner Tube, 20" x 4"; 171, Casing, 20" x 4"; 172, Tire, 20" x 2 1/2"; 173, Axle.

174, Gas Tank, to Attach to Engine Bed; 175, Bamboo Brace Clip; 176, Flexible Gasoline Pipe; 177, Radiator; 178, Radiator Brace; 179-180, Propeller, Bolt & Tinned; 181, Propeller, Complete Not Tinned; 182, Cap Screw, Nickel Steel, 5/16-24 x 1 3/4; 183, Cap Screw, Nickel Steel, 5/16-24 x 2 1/4; 184-185, Spring Washer, 1/4 x 3/16 & 5/16 x 3/8; 186, Wing Pontoon, Complete; 187, Pontoon Paddles; 188, Hydro Drain Plug; 189, Hydro Braces; 190-191, Hydro Spacing Tube & Bolt, Short & Long.

CHAPTER III THE CURTISS MOTOR AND FACTORY

The history of the Curtiss motor goes back to the early days at Hammondsport; it was the keynote of the development of the motorcycle, the airship, the aeroplane, and the hydro. From a crude single-cylinder engine used on an experimental bicycle, the motor has developed to an eight-cylinder engine giving over eighty horsepower, on which the reliability of the Curtiss aeroplane is dependent. Indeed, flight itself, in the history of the world, was delayed until the development of the gas engine made it possible to get a power that was applicable for this purpose, and one that was, at the same time, light enough.

To describe the motor intelligibly to one who has had no acquaintanceship whatever with gas engines would require many chapters, but to those who have ever examined automobile, marine, or other motors, the following technical data will give an idea of the distinctive feature of this aeroplane motor.

MOTOR DESIGN AND MATERIAL.

Crankshaft:

The crankshaft is supported in five bearings of more than ample size. It is extremely difficult, if not impossible, to design a shaft which will be light enough for aeronautical purposes, and still be sufficiently rigid without a special support. The propeller end of the shaft is supported in two places eleven and three-eighth inches apart, at one end in a plain bearing two and seven-sixteenth inches long and at the other in a combined radial and thrust ball bearing of ample size. This construction is stronger than is the case where the propeller is mounted immediately behind the last main bearing proper or even in some cases carried at a distance of several inches from the bearing without support. Any lack of mechanical or thrust balance is multiplied and transmitted directly to the last crank throw, the tremendous racking and twisting strain thus occasioned causing ultimate failure.

The crankshaft is made of imported Chrome-Nickel steel, properly heat treated. This steel, particularly after heat treatment, has an enormous tensile strength combined with a very high elastic limit and great resistance to fatigue and crystallisation.

Connecting Rods:

The connecting rods are machined from a solid Chrome-Nickel steel forging, heat treated. The body of the rod is tubular, which cross section gives a maximum strength with minimum weight. Rough forging weighs five pounds; finished weight one pound eight ounces.

Piston:

The piston is long enough to give sufficient bearing surface to sustain the side thrust from the connecting rod and at the same time weighs but two and one-half pounds. The domed head, with properly placed ribs, assures strength. The piston pin bearing is seven-eighth inches diameter by two and three-fourth inches long. Reversing common practice, the pin turns in the piston instead of the rod end, as considerable gain in bearing surface is thus made.

Engineers will appreciate that with a combined piston and rod weight of four and one-half pounds, the strains from twenty-two hundred reversals of motion per minute at normal speed are very slight.

It has three rings together with fourteen oil grooves aiding the rings in retaining compression and assisting the oiling. All pistons are rough turned and then thoroughly annealed before grinding, to insure against warping in service.

The piston rings are of clean springy iron, ground all over. As a ring must be tight on the sides as well as where it comes in contact with the cylinder, there must not be a variation in width of over a quarter thousandth of an inch.

Cylinder:

The cylinder is symmetrical in design, insuring even expansion without distortion.

Valve-in-the-head construction gives an efficient shape of combustion chamber; the compact charge fired in the centre giving quick, complete combustion, and the large valves give free ingress and egress for the gases.

The water jacket is brazed to the cylinder-casting autogenously, the metal being a composition of nickel and copper known as "Monel" metal, which is proof against corrosion.

Cylinders are bored, ground and finished by lapping, to get a glass smooth surface.

Water Circulation:

The water circulation is so carried out that all cylinders are cooled equally, the water pump being divided by a partition which passes water in equal quantities to each set of four, thus avoiding any possibility of a steam-trap on one side causing all the water to pass through the other side. The pump is driven from the crankshaft by a floating joint. The pump shaft is made of a carbon spindle steel.

A portion of the hot water is returned through the carburetor water jacket, which is essential with present day gasoline, particularly in cold weather or high altitudes.

Lubrication:

The lubrication is a combined circulating and splash oiling system. A gear driven oil pump submerged in the oil pan forces a constant stream of filtered oil through the hollow cam shaft bearing, thence to each individual cam shaft bearing, thence to the main crankshaft bearings whence it is forced through the hollow crankshaft and cheeks to the crank pins, the surplus replenishing the oil pan into which the rods dip, thus oiling the cylinder walls by splash and also filling oil pockets on each main bearing, as an additional insurance against their running dry.

The pump is driven off a bevel gear integral with the crankshaft and is of the gear type, being without valves or moving parts other than two simple spur gears. It is entirely enclosed in a fine mesh screen through which the oil must pass to reach the pump.

Valves:

The valves have cast-iron heads reinforced with a perforated steel disc embedded in the cast iron, the whole being electrically welded to a carbon steel stem. The cam shaft is hardened and ground and cams formed integral with the shaft. The cam contour is also ground, the valve timing being exactly the same in each cylinder.

Castings:

The majority of non-moving parts, including the crank case, are cast of special aluminum alloys. Recent laboratory tests have shown tensile strengths of as high as fifty thousand, five hundred pounds per square inch.

Weight:

The weight of model "A" motor alone is two hundred eighty-five pounds–three and eight-tenth pounds per horse-power. The weight of power plant including propeller, radiator, and necessary connections is three hundred forty-seven pounds.

Note that the forty horse-power cylinder motor weighs one hundred seventy-five pounds and gives a thrust of three hundred ten pounds when equipped with a seven foot diameter by six foot pitch propeller turning at nine hundred revolutions per minute. The pitch speed of the propeller at this rate is in excess of a mile a minute.

Gas-Consumption:

The consumption of gas is three-fourths pint per horse-power per hour. The engine can be throttled and consumption reduced in nearly direct ratio to the horse-power developed.

Consumption on full throttle per hour is seven and one-fourth gallons gasoline and one gallon of oil. The oil capacity of the small pan is four gallons; of the large pan, six gallons.

Testing and Power:

Each engine is given an extended run with propeller load. After giving the required standing thrust at the proper speed, the engine is completely torn down for inspection and carbon removed. After assembling, it is given a second test on a water dynamometer, which gives the horse-power developed.

Miscellaneous:

Few people realise that the aeronautical motor is subjected to usage equalled by few internal combustion engines. The average car engine is seldom run on full throttle for extended periods. The marine engine is ordinarily a very heavy, slow speed machine. The aeronautical motor, to run at the high speeds under full load demanded to-day, must of necessity be designed with this fact in mind, and particular attention paid to numerous weaknesses apt to develop under this treatment.

Adding to the above the necessity for minimum weight while still retaining a sufficient factor of safety in all parts, it is evident that an aeronautical motor must be designed as such and not be a modified edition of an automobile engine with a few pounds removed here and there.

PARTS OF CURTISS MOTOR–A COMPLETE LIST.

1-5, Breather Pipe Cap Screw & Flange, Collar, Cap & Clip; 6, Ball Bearing (Radial); 7-8, Crank Case, Upper Half & Lower Half; 9-10, Crank Case Bolt, Small & Large; 11, Crank Shaft.

12, Cam Shaft; 13-15, Cam Shaft Bearing, Front, Centre, & Rear; 16, Cam Shaft Bearing Sleeve, Rear; 17-18, Cam Shaft Gear & Retaining Screw; 19-20, Cam Shaft Bearing Clamping Screw, Centre, & Retaining Screw; 21, Cam Follower Guide Stud; 22, Cam Follower Guide Screw; 23, Cam Follower; 24-25, Cam Follower Guide & Plug.

26, Cylinder; 27, Cylinder Tie Down Yoke; 28-29, Cylinder Stud, Long & Short; 30, Cylinder Stud Nut; 31-32, Connecting Rod & Bolt; 33, Connecting Rod Bolt Nut; 34, Compression Tee for Oil Pipe; 35, Compression Coupling Sleeve; 36-37, Cable Holder & Screw; 38-39, Cable Tube & End; 40-41, Cable Tube Clip & Screw; 42, Carburetor Water Pipe Clip.

43, Exhaust & Inlet Valve; 44, Exhaust Valve Spring; 45, Felt Oil Retainer for Rear Thrust Bearing; 46, Felt Oil Retainer for Magneto Gear; 47, Gasket for Intake Manifold; 48-49, Gear Case Cover & Screw; 50, Gear Cover Packing Nut; 51, Half Time Gear; 52, Intake Pipe Elbow; 53, Intake Pipe with 2 Union Nuts; 54-56, Intake Pipe Y & Support Base & Cap; 57-62, Intake Manifold, & Bolt, Bolt Nut, Cap Screw, Union Nut, & Elbow Cap Screw; 63, Intake Valve Spring; 64, Magneto Bracket; 65, Magneto Gear; 66-67, Magneto Bracket Cap Screw, Large & Small; 68, Magneto Base Cap Screw.

69, Main Bearing Stud Nut; 70, Main Bearing Stud, New; 71-73, Main Bearing Cap, Front, Centre & Rear; 74-75, Main Bearing Babbitt, Front, Upper, & Lower; 76-77, Main Bearing Babbitt, Centre, Upper & Lower; 78-79, Main Bearing Babbitt, Rear, Upper, & Lower; 80, Main Bearing Babbitt Clamping Screw; 81, Main Bearing Liner, Front & Rear; 82, Main Bearing Liner Centre; 83, Main Bearing Liners.

84, Nipple for Oil Pump; 85-86, Oil Pump & Leader Gear Shaft; 87-94, Oil Pump Follower Gear, Cover, Drive Pinion, Screen, Support Bolt, Cover Screw, Follower Gear Bushing, & Shaft Bushing; 95, Oil Pipe for Pump; 96-97, Oil Pump Compression Coupling & Nut; 98-99, Oil Sight, Base & Glass; 100-101, Oil Sight Glass Guard & Cap; 102, Oil Splash Pan; 103, Oil Bleeder Pipe; 104, Oil Bleeder Pet Cock.

105-107, Piston, Pin & Ring; 108-109, Pump Packing Nut, Large & Small; 110-114, Push Rod, End Bearing Pin Lock Screw, Spring, Spring Support, Forked End, & End Bearing Pin; 115, Propeller Bolt; 116-121, Rocker Arm, Support, Bearing Pin Set Screw, Tappet Screw, Support Cap Screw, & Bearing Pin; 122-124, Spark Plug (Herz) Gasket,--& Wrench; 125-129, Thrust Bearing, End Clamp, Lock Ring, End Clamp Screw, End Clamp Bolt, End Thread Bolt Nut; 130, Valve Push Rod; 131, Valve Stem Washer; 132, Valve Stem Lock Washer.

133-135, Water Jacket, Inlet Nut, & Inlet; 136, Water Pump; 137-140, Water Pump Shaft, Support Stud, Impeller, & Driver; 141, Water Pump Friction Sleeve; 142-143, Water Pump Friction Washer, Front & Rear; 144-145, Water Pump Bushing, Front & Rear; 146, Water Pump Gasket; 147-149, Water Pump Universal Joint Member, Male, Female, & Spring; 150-151, Water Pipe, Right Hand, Bottom, & Left Hand, Bottom; 152, Water Pipe Outlet Elbow; 153-156, Water Outlet Top Pipes for Cylinders.

A VISIT TO THE FACTORY

A visit to the Curtiss factory is of interest to any one interested in machinery and there you will see the latest machines of all types, from powerful milling machines to a delicate modern "Printograph" that is almost human in its manner of getting out letters and printing, for it is a cross between a printing press and a typewriter. Another unique machine is one that carves out propellers from a laminated block of wood. One arm of this machine runs over a model, and the other, about two feet away, arranged to move exactly with it, and provided with a tool of cutting edge, forms the propeller blade with absolute accuracy, out of a block of wood placed parallel to the model. The cutting tool follows all the complex changes in the surface of the wooden propeller with the greatest ease and rapidity.

The brazing room, where the oxy-hydrogen torch is used to braze metal parts together, and the room where they weld the water jackets on to the cylinders, are places of special interest; the nickel plating room, japanning room, and the room where painting and drying are done, almost complete the tour of the various departments, but there still remain the wood-working shop, boat shop, assembling rooms, where the aeroplanes are put together and completely set up, and the motor testing room, where motors are run for whole days, ten hours at a time, driving an air propeller and showing on scales the amount of thrust given at all times.

Here you may also see a machine to make "brake tests" of the motors, by which is told how much horse-power the motors give. This machine consists of a large drum with a brake fixed against it and cooled by water so it will not get too hot. This brake absorbs the energy of the motor, which is measured by an arrangement of scales and lever arms.

There is a tremendous racket when the big motors are running at full speed in this small room, and the hillside rings with the roar of their fiery exhaust.

In the laboratory of the factory, where the designs and drawings are made, there is one of the most interesting pieces of apparatus in the whole plant. This is a "wind tunnel," where models of aeroplanes are tested and where experiments are tried to see what occurs in the stream of air. Here tests are made which assist in determining what the best form and shape of objects such as upright posts and exposed parts shall be and where a measure of their relative resistances may be made. The tunnel itself consists of a square box with a propeller or fan mounted at one end to create a draft or current of air which passes through a screen to cause it to assume uniform motion. There is a window in the tunnel through which the observer can see the action of the objects to be tested. Varying the speed of the fan varies the speed of the air current and its pressure, and in this manner the stream-lines of air under the varying conditions and the effect upon models of different forms and shapes may be studied to enable refinements to be made in the aeroplane's construction.

Down on the shore of Lake Keuka, about a half mile from the factory, are the aeroplane sheds and the flying field. Here is where the aviation school is situated, and where flyers are made. Over the smooth field, the pupils start with the four-cylinder "grass cutters," or machines hobbled so they cannot get but a little way off the ground. They hop, hop, hop, almost all day long, one after the other taking regular turns, and now and again varying the monotony by being called away by the flying instructor to take a real flight in the hydroaeroplane out over the lake to get accustomed to the upper air, and to the high speed of the big machine.

Later in his course of instruction, the student takes out an eight-cylinder machine and flies around in circles over the field until he is able to take the test for his Aero Club of America License, which requires him to make two series of figure eights around two pylons fifteen hundred feet apart, landing each time within one hundred and fifty feet of a mark and rising to an altitude greater than two hundred feet.

This is the goal of the novice, and after his test, the student is ready to fly as far and as fast as he likes. He has become the complete airman.