First, as to the instrument: a good substantial stand is desirable, one that will not readily vibrate. The microscope shown in Fig. 6 is a cheap and commendable form, and good work can be done by this instrument, which is made by Ross, London. The stand carries the body-tube, and at the lower end is placed the objective, so called, because the image of the object (which rests upon the stage as shown) under examination is first focussed by it and conveyed along the body-tube.

The top end of the said tube contains the eye-piece, so named because by its aid the eye is allowed to receive the image duly focussed and enlarged.

As a rule, beginners work with one objective only, generally a one inch.

A much higher power than this is necessary if the fibre in question is to be seen at its best, and for the purpose of this chapter a quarter inch objective will be used.

Underneath the stage, which is pierced by a circular aperture, is a diaphragm. This regulates the quantity of light which is to be transmitted by means of the silvered reflector shown in the illustration.

As a rule, two reflectors are fixed in the same holder; one a concave mirror, the other a plane one. The former brings the rays of light to a point or focus while the latter simply passes the beam of light along just as it received it, viz., as a parallel beam of light.

In examining fibres the concave mirror will be of most use. An ordinary lamp is usually good enough for the light required, the one figured being very suitable and having a tube-like arrangement of wick. Behind the body-tube are two forms of adjustment, coarse and fine. The latter is worked by means of the milled screw, conical in shape, which is found immediately behind the coarse adjustment. The operator is supposed to have had some slight experience in the manipulation of the microscope. The slide is now placed upon the stage. Fine Sea Islands cotton is mounted in Canada Balsam and protected by a small circular cover glass.

Now rack down the body-tube by means of the coarse adjustment until within ¹⁄16 of an inch of the cover-glass of the slide. Now see that the light from the lamp is fully on the cotton strands. Rack up or down, as the case may be, with the fine adjustment, and a wonderful sight meets the eye, for the cotton viewed through the microscope is altogether unlike what we should expect it to be.

Running completely across the field are a number of strands, varying in thickness, form and natural twist. What is meant by natural twist is very clearly shown in Fig. 7.

Most people have seen india-rubber tubing or piping such as is used in the chemical laboratory or that often found attached to feeding bottles. Take about a foot of this and hold one end firmly. Abstract the air by means of the mouth, and it will be found that immediately the air is taken out the tube collapses. Now if the rubber be variable in thickness, here and there along these lines of least resistance will be found certain twists, and it is the same kind of twists which can be so distinctly seen as the cotton fibre is viewed through the microscope. They are exceedingly irregular in number, on equal lengths of the same single fibre. When they run for some length, and are fairly regular, the edges appear like wavy lines or corrugations. It will now be seen by the reader why these twists are so invaluable in spinning: locking and intertwining with each other, they materially assist the spinner in building up a long and continuous thread.

As the slide containing the cotton is moved laterally, it will be seen that this twisting of the fibre is continued for almost the whole length, and as many as 300 twists have been counted on a single filament. In some, the fibre tapers slightly, becoming more and more cylindrical as the end most remote from the seed is approached, until it is quite solid. These stiff ends soon disappear after the cotton has been treated in the early processes of manufacture. Thus there may be found in almost every sample of cotton what are called ripe, half-ripe and unripe cotton. The last-named kind result from—

Then again in the same boll all fibres do not ripen together just as all apples on the same tree do not ripen together.

Immature or unripe cotton cannot be dyed, and when small white specks are seen in any dyed fabric they are often due to the fact that unripe cotton has been used in the manufacture of the cloth.

Measurement of the Cotton Fibre.—This is not at all a difficult matter, and the ordinary student may, by means of very simple and inexpensive apparatus, obtain fairly satisfactory results in the measurement of fibres.

There is a choice of one of three methods, viz.:—

This latter method is certainly the least expensive, and for all practical purposes can be safely recommended.

A stage micrometer consists of a slip of glass 3" × 1" on which are marked divisions of an inch, usually ¹⁄100ths and ¹⁄1000ths. As a rule these markings are protected by means of a small cover-glass.

Eye-piece micrometers vary much in form, size and value, but the one which is here described is of the simplest type. It consists of two circular pieces of glass carefully cemented together. On one of the inner surfaces are marked usually the ¹⁄100ths divisions of an inch. In some ¹⁄200ths are marked. If the top lense of the eye-piece be unscrewed, a diaphragm will be found on which the eye-piece micrometer will easily rest. Screw on the top lense again and, generally, the eye-piece will be ready for use. If the micrometer is not properly in focus after a few trials, it may easily be made right. In order, then, to measure the diameter of a single fibre of Sea Islands cotton, fit in the quarter inch objective and place the stage micrometer in position on the stage. First, focus the fine lines which are plainly to be seen, and remember the lines which are farthest apart are ¹⁄100th of an inch; the others ¹⁄1000th of an inch.

As a rule, these lines run from N. to S. of the field; in other words, from top to bottom across the circles of light. Now look at the divisions in the eye-piece micrometer, which are ¹⁄100th of an inch apart.

It will be found often that an exact number of these divisions fill up one of the ¹⁄100th divisions of the stage micrometer markings. If an exact number are not found, the draw-tube at the top end of the body-tube should be withdrawn until an exact number is found to lie within two lines of the lower micrometer.

Suppose twenty-two of the spaces on the eye-piece micrometer just cover one of the divisions (¹⁄100th of an inch) on the stage micrometer. Then it is clear that each division of the former represents ¹⁄100 × ¹⁄22 of an inch, or ¹⁄2200th of an inch. For every fresh objective used, a fresh estimation of eye-piece and stage micrometer ratio is necessary. Having now got in the eye-piece micrometer a unit of measurement, it becomes a comparatively easy matter to measure the fibre.

Remove the stage-micrometer and put a slide of Sea Islands cotton in its place. Focus the fibre and observe the number of divisions or parts of a division covered by any particular fibre, and its measurement is at once known. Thus if a single filament covers two of the divisions then it is ²⁄2200th of an inch in diameter, or ¹⁄1100th of an inch. Exactly the same method is adopted if it is desired to measure the diameters of sections of the same fibres.

The making of the drawing of a fibre, either transverse or horizontal section, is not at all a difficult matter.

All that is needed is what is known as a camera lucida. This consists of a brass fixing for the eye-piece end of the body-tube and a small reflecting prism. This prism receives the image of the objective, and reflects it in this case at right angles downward on to a sheet of paper, which is placed beneath for the purpose of tracing the said image.

Focus the object, first having the microscope in a horizontal position. This will not be a difficult matter. Now remove the cap which fits on the eye-piece, and fix on the camera lucida as shown in the illustration (see Fig. 6). Adjust this until the image of the fibre is seen. Usually one or two smoke-coloured glasses are fixed below the prism, and these are now brought into position so as to allow the image of the fibre to pass through them. Place a sheet of drawing paper directly under the camera lucida, sitting as shown in the illustration. After a few trials it will not be a difficult matter to follow the outline of the image by means of a black lead on the paper as is shown in the figure. In this way many useful working drawings can be made, and a little careful calculation will give the amplification of the drawing after it is made.

CHAPTER V.

Now the picking of cotton is not at all an easy operation, long continuous bending, a hot sun (for it is a rule scarcely ever broken that cotton must not be plucked unless the sun is shining upon it), a constantly increasing weight round the neck or on the arm, monotonous picking of the cotton from the bolls without bringing away any of the husk or leaf—all tend to make the work of the picker very trying and tiresome. The plantation hands must be early at work, and while the day is very young they are to be seen wending their way, ready to begin when the sun makes its appearance. Often the clothes of the workers are quite wet with the early morning dews. This is specially the case in September and October. By ten o'clock a hot blazing sun streams down upon the pickers as they diligently relieve the heavy-laden bushes of the white fleecy load of cotton. As each picker fills his or her bag, it is quickly emptied into a larger receptacle, and ultimately carried away to the gin house, where it is desirable the cotton should be housed before the night dews come on and consequently damage materially the cotton which the pickers have been careful to pick while the sun was on it.

Mr. Lyman, in his book on the Cotton Culture in the States, says: "It seems like very easy work to gather a material which shows itself in such abundance as fairly to whiten the field, but let the sceptic or the grumbler take a bag on his shoulders and start in between a couple of rows. He will find upon taking hold of the first boll that the fibres are quite firmly attached to the interior lining of the pod, and if he makes a quick snatch, thinking to gather the entire lock, he will only tear it in two, or leave considerable adhering to the pod. And yet he may notice that an experienced picker will gather the cotton and lay his fingers into the middle of the open pod with a certain expertness which only practice gives, the effect of which is to clear the whole pod with one movement of the hand."

Knowing how intensely monotonous and dreary the work of cotton picking is, Mr. Lyman advises the planters to allow a very fair amount of liberty so far as merrymaking is concerned, and he says on this point that "though too much talking and singing must interfere with labour, it is earnestly recommended to every cotton grower to take care to secure cheerfulness if not hilarity in the field. Remember that it is a very severe strain upon the patience and spirits of any one, to be urged to rapid labour of precisely the same description day by day, week by week, month by month. Let there be refreshments at the baskets, a dish of hot coffee in a cool morning, or a pail of buttermilk in a hot afternoon, or a tub of sweetened water, or a basket of apples."

As a rule the cotton gathered on one farm, which has, generally speaking, had something like uniformity in method of cultivation, will produce cotton varying very little in quality and weight.

Hence on large farms there will be something like uniform quality of cotton produced. It will, however, be clear to the general reader that on the small farms of India, say where sufficient cannot be gathered on one farm, or perhaps on a few farms, to make one bale, there will not be that uniformity which is desirable, hence Indian cotton, especially of the poorer types, varies a great deal more than the American varieties. When the hands have gathered sufficient to fill the carts drawn in America usually by mules, and in India by oxen, the cotton is taken to houses in which the seeds are separated from the fibre. This process is called "ginning."

It is astonishing to find how tenaciously the fibres cling to the seed when an attempt is made to separate them. At first much loss was occasioned because of the brutal methods employed, and now even with very much more perfect machinery a good deal of the cotton fibre is injured in the ginning process.

At present, most of the cotton produced in various parts of the world is ginned by machinery, though in India and China foot gins and other primitive types are still employed.

It should be stated that where a large production of cotton is desired the foot gin or even what is known as the "Churka gin" (which consists of a couple of rollers turned by hand) is never employed. Only a few pounds a day of cotton can be separated from the seeds when this method is adopted.

The following extract from a lecture by the late Sir Benjamin Dobson will be of interest here, as showing what is done at an American ginnery:

"The farmer brings the cotton to the mill in a waggon, with mules or oxen attached; the cotton is weighed, and then thrown out of the waggon into a hopper alongside. From this hopper it is taken by an elevator, or lift, either pneumatic or mechanical, and raised to the third story of the ginning factory. There it is delivered into another part of the room until required. When the cotton is to be ginned it is brought by rakes along the floor to an open sort of hopper or trunk, and from here conveyed to the gins below by travelling lattices.

"In the factory of which I am speaking there were six gins, all of them saw-gins. Each gin was provided with a hopper of its own, and the attendant, when any hopper was full, could either divert the feed to some other gin, as he required, or stop it altogether. The gins produced from 300 pounds to 350 pounds per hour. The cotton is dropped from the condenser, in front of the gin, upon the floor close to the baling press, into which it is raked by the attendant and baled loosely, but only temporarily. The seed falls into a travelling lattice, and is conducted to a straight cylindrical tube, in which works a screw. This takes it some one hundred yards to the oil mill. There the seed is dropped into what are known as 'linting' machines, and as much as possible of the lint or fibre left upon the seed is removed.

"These linting machines—practically another sort of gin—deliver the cotton or waste in a kind of roll, which is straightway put behind a carding engine. Coming out of the carding engine it is made into wadding by pasting it on cardboard paper, for filling in quilts, petticoats, and for other purposes. When the seed has passed the linting machine, it is taken, still by a lattice, to a hulling machine. This machine will take off the outside shell, which is passed to one side, while the green kernel of the seed goes down a shoot. The seed fills certain receptacles placed in the oil press, and is submitted to a hydraulic press. The result is a clear and sweet oil, which I am credibly informed is sold in England and other countries under the name of 'olive oil.' The remains of the green kernel are then pressed into what are termed cattle cakes, or oil cakes, for feeding cattle."

But the reader is probably asking, what is a gin like?

The illustration seen in Fig. 9 is a gin which goes by the name of the "single-acting Macarthy gin," so called because it has only one oscillating blade for removing the fibre from the seed. The back of the machine is shown in the figure. This process at the best is a brutal one, especially when certain gins are employed, but the one figured here is considered to do little damage to the fibre when extracting the seed.

The gin shown in Fig. 9 is of simple construction, consisting of a large leather roller about 40 inches in length and 5 in diameter. "The roller is built up by means of solid washers, or in strips fastened on to wood, against which is pressed a doctor knife.

"The cotton is thrown into a hopper, and, falling, is seized by the friction of the leather and drawn between the doctor knife and the leather surface. Whilst this is taking place, there is a beater knife which is reciprocated at a considerable speed and which strikes the seed attached to the cotton drawn away by the leather roller. The detached seed will then fall through a grid provided for the purpose. A single-action gin should produce about 30 pounds of cleaned cotton per hour."

Another gin which does considerable damage to fibre, especially if it be over-fed, is still in use in the States. This was the invention of an American named Eli Whitney, and has been named a "saw-gin."

If the reader can imagine a number of circular saws (such as are to be seen in a wood-sawing mill) placed nearly together on a shaft to form an almost continuous roller, he will have a good idea of what the chief part of a saw-gin is like.

As the cotton is fed to the machine, the saws seize it and strip the cotton from the seeds, which fall through grids placed below the saws. The cotton is afterward stripped from the saws themselves by means of a quickly revolving brush which turns in the opposite direction to the saws. This gin is best suited to short stapled cottons, especially such as are grown in the States. For the longer fibred cotton this gin is not well adapted, much injury resulting to the cotton treated by it.

After the cotton is ginned, it is gathered into bundles and roughly baled. When a sufficient quantity has been so treated, it is carried to the "compressors," where the cotton undergoes great reduction in bulk as a result of the enormous pressure to which it is subjected.

For the general reader it will scarcely be necessary or wise to describe a "cotton press" in detail. Let it suffice to say that by means of a series of levers—in the Morse Press seven are used—tremendous pressure can be obtained. Thus for every 1 pound pressure of steam generated there will be seven times that pressure, if seven levers are used. When 200 pounds pressure of steam is up, there will be 1400 pounds pressure per inch on the cotton. So great is the pressure exerted that a bundle of cotton coming to the press from the ginnery, 4 feet in depth, is reduced to 7 inches when drawn from the compressor. While in the press iron bands are put round the cotton, and readers will have frequently seen cotton on its way to the mills having these iron bands round it.

The following table shows the number of bands which are found on bales coming to England from cotton-growing countries:—

Within the last few years an entirely new industry has been started in some of the Southern States of America.

Up to recently the bales sent to European countries from America were all of the same type as shown by the centre bale in Fig. 10.

Now a vast quantity of cotton is being baled in the form as shown in Fig. 11, and what are known as cylindrical bales are being exported in large numbers. In the "Round Bale" Circular of the American Cotton Company, it is stated that from the 21st November, 1896, to January 2nd, 1897, no less than 1443 round bales were turned out of the factory at Waco in Texas. The total weight of these bales was 614,832 pounds, giving an average of 426 pounds per bale.

By means of a press the cotton is rolled into the form as shown in the illustration. The press makes a bale 4 feet long and 2 feet in diameter and weighs over 35 pounds per cubic foot or 50 per cent. denser than the bale made under the system as shown in Fig. 10.

It is claimed for this new system that the regularity of the size of the bale, 4 x 2 feet, makes it pack much closer than the irregular turtle-backed bales as usually made on the old system.

Under the new style the cotton is pressed gradually and not all at once. For this reason it is claimed that the fibre is not injured and the cotton arrives at the mill with the fibre in as good condition as when it left the gins.

"Bagging and ties are entirely dispensed with, as the air is pressed out of the cotton and it has no tendency to expand again, and the covering needed is only sufficient to keep the cotton clean."

From a number of experiments it is proved that the "round bale" is both fireproof and water proof.

From the illustration of the round bale shown in Fig. 11, it will be seen how readily this new form of bale lends itself to greatly aiding the operatives in the opening processes in the mill. The roll which lies on the floor like a roll of carpet could be so fixed that the cotton could be fed to the opener by being unrolled as shown in the illustration.

At present the round bale system is not popular and it remains to be seen whether it will commend itself to cotton spinners.

CHAPTER VI.

On the field there are the operations of collecting and ginning, that is, separating the raw cotton from the seeds. To the stranger it is very astonishing that as many as 66 to 75 pounds of seed are got from every 100 pounds of seed cotton gathered. Then in or near the cotton field the process of baling is carried out. Thus there are collecting, ginning and baling, as preliminary processes.

When the cotton arrives in bales at the mill (see Fig. 10), in which it is to be cleaned, opened and spun, it is first weighed and a record kept.

In the mill the first real operation is the taking of quantities of cotton from different bales of cotton from various countries, or different grades from the same country, and "mixing" so as to secure a greater uniformity in the quality of the yarn produced. In this process it is now the common practice to use a machine termed the "Bale Breaker," or "Cotton Puller."

The second important process carried out in the mill is "opening." By this the matted masses of cotton fibres are to a great extent opened out, and a large percentage of the heavy impurities, such as sand, shell, and leaf, fall out by their own weight. It is now also usual at this stage to form the cotton into a large roll or sheet called the "lap."

Immediately following the "opening" comes "scutching," which is merely a continuation of the work performed by the "opener," but done in such a way that greater attention is bestowed upon the production of an even sheet or "lap" of cotton.

The cotton at this stage is practically in the same condition as it was when first gathered from the tree in the plantation.

Carding comes next in order, and it should be observed that this is one of the most beautiful and instructive operations carried on in the mill.

The process of opening out the cotton is continued in this operation to such an extent that the fibres are practically individually separated, and while in this condition very fine impurities are removed, and many of the short and unripe fibres which are always more or less present are removed. Before leaving the machine the fibres are gathered together again in a most wonderful manner and converted into a "sliver," which for all the world looks like a rope of cotton, a little less than an inch in diameter.

In most mills "drawing" succeeds "carding," this operation having for its object (1) the doubling together of four to eight slivers from the card and attenuating them to the dimension of one so as to secure greater uniformity in diameter. (2) The reduction of the crossed and entangled fibres from the card into parallel or side by side order.

After "drawing," the cotton is brought to and sent through a series of machines termed "Bobbin and Fly Frames." There are usually three of these machines for the cotton to pass through, to which are given the names of "Slubbing," "Intermediate," and "Roving" Frames.

Their duties are to carry on the operation of making the sliver of cotton finer or thinner until it is ready for the final process of spinning, and incidentally to add to the uniformity and cleanliness of the thread of cotton.

The final process of spinning is chiefly performed on one of two machines, the "Mule" and the "Ring Frame," either of which makes a thread largely used without further treatment in a spinning mill.

Sometimes, however, the thread is further treated by such operations as doubling, reeling, gassing, etc. It should be added that in the production of the finest and best yarns an important process is gone through, named "combing."

This may be defined as a continuation of the carding process already named before to a much more perfect degree. The chief object is to extract all fibres below a certain required length, and reject them as waste. There is as much of this latter made at this stage of manufacture as that made by all the other machines put together, that is, about 17 per cent. Of course it will be readily seen that this is a costly operation and is limited entirely to the production of the very best and finest yarns.

This process necessitates the employment of a machine called a "Sliver Lap" and sometimes a "Ribbon Lap Machine" in order to put the slivers from the carding engine into a small lap suitable for the "creel" of the "Combing Machine."

Cotton Mixing and the Bale Breaker.—As before stated, the first operation in the mill is the opening out of bales of raw material and making a "mixing." Of course the weight of the bale is ascertained before it is opened.

All varieties of cotton vary in their commercial properties, this variation being due to a number of causes. From a commercial value point of view, there is an enormous difference between the very best and the very worst cottons; so much so, indeed, that they are never blended together. Between these two extremes there is a well-graded number of varieties and classifications of cotton, and some approximate so closely to others in quality, that they are often blended together in the "mixing."

Further than this, the same class of cotton often varies in spinning qualities from a number of circumstances that need not here be named. This is, however, an additional reason why cotton from various bales should be blended together in order to secure uniformity.

A cotton "mixing" may be described as a kind of "stack," resembling somewhat the haystack of the farm yards.

The method usually pursued in making this mixing is somewhat as follows:—A portion of cotton from a certain bale is taken off and spread over a given area of floor space. Then a similar portion from another bale is placed over the first layer already lying on the floor.

The same operation is followed with a third and fourth layer from different bales, and so on with as many bales as the management consider there are variations in quality, the larger the mixing the better for securing uniformity of yarn.

When it is desired to use the cotton, it should be pulled down vertically from the face of the "mixing," so as to secure a fair portion from each bale composing the mixture. Before spreading the cotton out it is usually pulled into pieces of moderate size by the hands of the operative.

During recent years it has become the very general practice to use a small machine called the "Bale Breaker" or "Cotton Puller," and to have also working in conjunction with this machine long travelling "lattices" called "mixing lattices." These perform the operation of "pulling" and "mixing" the cotton much more quickly and effectively than by hand labour.

The "Cotton Puller" or "Bale Breaker" (see Fig. 12) simply consists, in its most useful form, of four pairs of coarsely fluted or spiked rollers of about 6 inches diameter with a feed apron or lattice such as is shown in the illustration.

The method adopted with the "Bale Breaker" and "mixing lattices" in use is as follows:—

The various bales of cotton intended for "mixing" are placed very near to the feed apron of the Bale Breaker, and a layer from each bale in succession is placed on the apron. The latter feeds the cotton at a slow rate to the revolving rollers of the machine, and as each pair of top and bottom rollers that the cotton meets is revolving more rapidly than the preceding pair, the result is a pulling asunder of the cotton by the rollers, into much smaller pieces, quite suitable for the next machine. The Bale Breaker delivers the cotton upon long travelling aprons of lattice work, which carry the cotton away and deposit it upon any desired portion of the floor to form the "mixing."

Opening.—The name of the next process, viz., "opening," has been given it because its primary function is "to open" out the cotton to such an extent that the greater bulk of the seed, leaf, sand, and dust is readily extracted. The details of this machine and indeed practically of all machines used in cotton spinning, vary so much with different makers, that it would be utterly out of place to deal with them here, so that it may be said at once, that all such points are entirely omitted from this treatment of the subject.

The essential and principal portions of the machines are practically identical for all makers, and it is with these only that it is proposed to deal, taking in all cases the best present-day practice.

The opener, then, is a very powerful machine, being in fact the most powerful used in cotton spinning, and the most important feature of the machine is the employment of a strong beater, to which is fitted a large number of iron or steel knives or spikes. These beat down the cotton and open it at a terrific rate, the beater having a surface speed of perhaps 4000 feet a minute. Various fans, rollers, and other parts are employed to feed the cotton to the beater, and to take it away again after treatment. It will perhaps best serve the purpose of our readers if the passage of the cotton be described through an opener of the most modern and approved construction, dealing with the subject in non-technical terms.

With this object in view, take for example what is termed "The Double Cotton Opener" with "Hopper Feed Attachment." This machine is shown in Fig. 13.

The Hopper Feed is about the most recent improvement of any magnitude generally adopted in cotton spinning mills. It is an attachment to the initial or feed end of an opener with the object of feeding the cotton more cheaply and effectively than it can be done by hand.

It may be said to consist of a large iron feed box, into which the cotton is passed in considerable quantities at one time. At the bottom of the feed box, or hopper, is a travelling apron which carries the cotton forward, so as to be brought within the action of steel pins in an inclined travelling apron or lattice. This latter carries the cotton upwards, and special mechanism is provided in the shape of what is termed an "Evener roller," to prevent too much cotton going forward at once.

The cotton that passes over the top of the inclined lattice or apron is stripped off by what is denominated the stripping roller, and is then deposited on the feed apron of the opener, where formerly it was placed by hand.

It may be said that one man can feed two machines with Hopper Feeds as against one without them, and in the best makes the work is done more effectively.

The feed lattice of the opener carries the cotton along to the feed rollers, which project it forward into the path of the large beater. It is here that the opening and cleaning actions are chiefly performed.

The strong knives or spikes of the beater break the cotton into very small portions indeed, and dash it against "cleaning bars" or "grate bars" specially arranged and constructed. Through the interstices of these bars much of the now loosened seed and dirt present in the cotton passes into a suitable receptacle, which is afterward cleaned out at regular intervals.

The opened and cleaned cotton is taken away from the action of the beater by an air current produced by a powerful fan. This latter creates a partial vacuum in the beater chamber by blowing the air out of certain air exit trunks specially provided. To supply this partial vacuum afresh, air can only be obtained from the beater chamber, and the air current thus induced, takes the cotton along with it, and deposits it in the form of a sheet upon what are termed "cages" or "sieve cylinders."

These are hollow cylinders of iron or zinc perforated with a very large number of small holes through which the air rushes, leaving the cotton, as it were, plastered on the outer surfaces of the cages.

It is usual to have a pair of these cages, working one over the other like the pair of rollers in a wringing machine.

The cotton now passes between two pairs of small guide rollers, and is fed by the second pair to a second beater, but of very different construction from the first one.

This consists of two or three iron or steel blades extending the full width of the machine and carried by specially constructed arms from a strong central shaft.

The edges of these beater blades are made somewhat sharp, and they strike down the cotton from the feed roller at the rate of 2000 or more blows per minute.

This of course carries the opening work of the cotton of the first beater to a still further degree, and as in this case the cotton is also struck down upon "beater bars" or cleaning bars, a further quantity of loosened impurities passes through the bars. As before, another powerful fan creates an air current by which the cotton is carried away from the beater and placed upon a pair of "Cages." From this point the cotton is conducted in the form of a sheet between four heavy calender or compression rollers, the rollers being superimposed over each other, and the cotton receiving three compressions in its passage.

This makes a much more solid and tractable sheet of cotton, and it is now simply wound upon an iron roller in the form of a roll of cotton termed a "lap," being now ready for the subsequent process, as shown in the illustration (Fig. 14).