The Story of the Cotton Plant - Part 7
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Part 7

"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 pa.s.sed the linting machine, it is taken, still by a lattice, to a hulling machine. This machine will take off the outside sh.e.l.l, which is pa.s.sed 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 ill.u.s.tration 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."

Image: FIG. 9.--Single-acting Macarthy gin.

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 quant.i.ty 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:--

No. of bands. Weight in lbs.

American bale 6 or 7 500 Egyptian " 11 700 Indian " 13 390 Turkish " 4 250-325 American Cylindrical bale -- 420-430 Brazilian -- 175-220

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.

Image: FIG. 10.--Bales from various cotton-growing countries.

Now a vast quant.i.ty 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 ill.u.s.tration. 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.

Image: FIG. 11.--Cylindrical rolls of cotton.

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 ill.u.s.tration 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 ill.u.s.tration.

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.

MANIPULATION OF COTTON IN OPENING, SCUTCHING, CARDING, DRAWING, AND FLY-FRAME MACHINES.

Before attempting to give the readers of this story an insight into the various operations through which cotton is made to pa.s.s, it may be advisable to briefly enumerate them first.

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 quant.i.ties 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 ma.s.ses of cotton fibres are to a great extent opened out, and a large percentage of the heavy impurities, such as sand, sh.e.l.l, 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 pa.s.s 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, ga.s.sing, 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."