Raw Cotton

RAW COTTON Cotton-ginning or separation of the lint from the seed, which is the first process of manufacture, is performed practically in the field in order to save unnecessary transport of the seed, which forms about two-thirds of the weight of the harvested crop. The ginning outturn, as it is called, or proportion of lint to seed cotton, fluctuates round about 33% and varies considerably with different varieties. As a rule the finest cottons give a smaller percentage of lint, but many of the cheapest short staple varieties, e.g., native West African, are also as low as 25%. On the other hand many of the short staple varieties in -India are reported to have given as high as 5o%, and after the World War a number of such varieties were introduced into America, where they gave about 40% as against the normal 33% for Upland cotton.

Ginning.

The separation of the lint from the seed is accom plished in various ways. Hand-picking at a very early stage gave place to the almost equally primitive bow-string formerly used in America, hence the name "Bowed Georgias," which is still applied to Upland cotton from the Atlantic States. In India the primitive churka is still used. With this primitive machine, worked by hand, about 5 lb. of lint is the daily output. A modern 'form of this type of gin is the Macarthy roller gin. A hand Macarthy roller gin worked by two men will clean about 4 to 6 lb. of lint per hour. A similar, but larger machine, requiring power to run it, will turn out over 1 oo lb. of Egyptian or 6o to 8o lb. of Sea Island cleaned cotton per hour. In America the saw gin is employed for cotton even a little over an inch staple, the use of the roller gin being confined to the American-Egyptian districts in the West, to which many of them were transferred when the growing of Sea Island cotton in the Carolinas was abandoned. The modern ginneries in America are highly efficient and are almost automatic, the whole operation being carried out by pneumatic suction, so that the cotton is hardly touched by human hands at all.

Outside the ginnery the farmer's wagon, which contains about 1,500 lb. of seed cotton, is backed under a suction flue which carries the cotton into the ginnery and drops it straight into the cleaning machines attached to the gin stands. From the gin the lint is carried pneumatically along the lint flue into the condenser above the baling box, into which it falls and is slightly pressed down by a mechanical tramper from above. The baling boxes are in duplicate on a revolving platform, and when one is filled it is swung round over the ram of the press which comes up from below and presses the cotton into the farmer's bale of about 480 lb. net weight, measuring 54in. x 46in. x 27in. with a density of about 15 lb. per cu.ft. For fuller details see the section COTTON, COTTON MACHINERY.

Baling and Pressing.

Up to the stage at which the farmer's bale is thrown out on the gin platform the system is entirely satisfactory. The density of the farmer's bale is low because it is intended to be re-pressed before export, and in view of this it is not entirely covered by the bagging, a gap of I tin. being lef t along each side and the ends, so that when further pressure is applied in the compress and the depth or thickness of the bale is decreased to about 3oin., the top and bottom pieces of bagging will meet and cover the bale. In the meantime, however, the farmer's bale passes through a process of handling and sampling which quickly destroys its efficiency as a protection. The custom of the trade is that samples must be taken out of the round sides of the bale. To do otherwise would require the use of an auger and the result would not have the open flaky appearance, like the leaves of a book, which the dealers desire in a sample. Every sample hole involves a great cut in the bagging, and when the bale is finally sold for shipment to a northern mill or for export, there may be six or eight of these great gashes in the covering, from which loose cotton falls at every opportunity. Before shipment or export, therefore, the bale is re-pressed at the compress. In this process the bands are removed, but in stead of putting on two new pieces of bagging, the old pieces are left with the addition of a number of patches of similar bagging, or still heavier material, which are supposed to be for the purpose of covering up the sample holes, but the real result is to make sure that the tare of the bale is not less than the traditional 6% of its weight. At the same time the handling of the bale in the compresses is so badly rushed that no time is allowed to make the best of a bad job, e.g., by pulling up the side cloths to make them meet and sewing up the bagging over the ends of the bale which is supposed to be done, but is in fact done very ineffectively. The result is that of ter its further journey to the seaport and then to its ultimate destination, the American bale is, as it has been described in a standard American book on cotton, "the clumsiest, dirtiest, most expensive and most wasteful package, in which cot ton or any other commodity of like value is anywhere put up." The cost of this unsatisfactory system is colossal, both in the actual loss of cotton from the torn bales and also in unnecessary space taken up in trains, on board ship and in the warehouses, as well as in higher premiums of fire insurance.

Agitation for reform has been going on for many years on two lines. The one is the improvement of the presses so as to produce a higher density bale which would save freight space. Consider able advance was made in this direction during the World War owing to the scarcity of freight room and high charges. But this alone does not go to the root of the matter which lies in the proc ess of sampling between the ginnery and the compress. To meet this it has been proposed that a higher density bale should be made at the ginnery by the use of a gin compress, and that samples should be taken from the bale before gin compressing, so that it would not be necessary to cut the bale afterwards. This reform, however, would cut across the whole existing organization of the industry, and owing to the difficulty of changing the customs of the trade and the opposition of vested interests, especially in the compresses, practically no progress had been made up to 1927. Another line of reform was the introduction of the round bale in which the cotton is wound round a wooden core under high pres sure, but this had not reached the stage of anything like general adoption in 1927.

In Egypt the baling system is entirely different, the bale from the up-country ginneries being entirely remade with new bagging and ties at the compresses in Alexandria before shipment. The weight of the bale is about 75o lb. net and its density about 35 lb. per cu.ft. In India the baling system, especially for export, is also excellent. The bale weighs, as a rule, about 400 lb. though many for export are about 500 lb. and the density is about the same as the Egyptian. In practically all the British colonies the bale weight is 400 lb. and the whole system of handling the bale is thoroughly efficient.

all parts of the cotton-growing world transport is of the utmost importance, for the crop is both heavy and bulky and its movement from the field to the ginneries and thence to the port, and finally to the mills, involves in most cases a long and expensive series of different stages and means of transport. In the old-established countries such as America, India and Egypt, transport facilities, though sometimes primitive, are now on the whole adequate, great improvements having been made, especially in road and rail transport, during the last quarter of a century. The whole of the American cotton belt is well supplied with the ordi nary facilities of transport by river and rail, while the sea services both coastwise to the northern American ports and to all European ports leave nothing to be desired. In Egypt methods of transport are much more primitive, but the unpressed up-country bale of 400 lb., in which form most of the cotton is brought to the gin neries or other concentrating points up-country, is very easily handled, especially by camel. The Delta light railways are also very efficient. The transport system in Egypt is greatly facilitated by the fact that all the crop is finally concentrated at one point— Alexandria, to which such roads as now exist in the country gravi tate, as well as the western part of the irrigation canal system, the canals being in themselves one of the principal means of transport. From Alexandria shipping services both to America and Europe are thoroughly efficient, while East-bound traffic finds equally good facilities from Port Said. In India, the railway sys tem now covers the whole of the cotton country adequately, and the shipping services for export both eastwards and westwards are ample.

It is, however, in the new cotton-growing countries, such as East and West Africa, that the problem of transport becomes both most important and most difficult. All over Africa there are large areas where cotton growing could be rapidly extended if transport were available. The development of the Cape to Cairo route—a composite scheme of rail and water transport in alternate sections —has become the backbone of many similar systems working East and West. In addition to these means of communication by rail or steamer there has been considerable development in the construction of roads for wagon traffic by motor or animals in most of the cotton-growing centres. In some cases, however, e.g., Uganda, the question is complicated by the tsetse fly.