Page:The American Cyclopædia (1879) Volume V.djvu/410

406 appearance of frost. The height of the picking season is in October. The picking is by hand. Lines of pickers, generally negroes, male and female, with wide-mouthed sacks suspended from their shoulders or waists, pass between the rows of plants, and gather the fleecy cotton from the open pods, which is carried in sacks and deposited in baskets at the ends of the rows. Each person will pick an average of from 200 to 300 lbs. per day. Successive pickings are made as the bolls ripen. The cotton is brought from the field in wagons to the gin house, generally a plain wooden structure two stories high. If damp it is dried in the sun. The next step is the process of ginning, or the separation of the fibre from the seed. This process was at first performed by hand, which was a very tedious operation owing to the tenacity with which the cotton clings to the seed; but since the great invention of the cotton gin by Eli Whitney, in 1793, it has been done by that machine with the most beneficial results. So great was the effect of this invention upon the cultivation and manufacture of cotton, that its production and consumption increased with marvellous rapidity.



The principle and mechanism of the cotton gin are both simple. The main features consist of a cylinder, generally about 4 ft. long and 5 in. in diameter, upon which is set a series of circular saws, about half an inch apart, and projecting about two inches above the surface of the revolving cylinder. A mass of cotton in the seed, separated from the cylinder by steel bars or grating, is brought into contact with the numerous teeth on the cylinder. These teeth catch the cotton while playing between the bars, which allow the lint but not the seed to pass. Underneath the saws is a set of stiff brushes on another cylinder revolving in the opposite direction, which brush off from the saw teeth the lint which they have just pulled from the seed. The remaining feature is a revolving fan for producing a current of air to throw the light and downy lint thus liberated to a convenient distance from the revolving saws and brushes. These are the essential principles of the cotton gin as invented by Whitney, and as still used; but in various details and workmanship, it has been the subject of many improvements, the object

of which is to pick the cotton more perfectly from the seed, to prevent the teeth from cutting the staple, and to give greater regularity to the operations of the machine.



The ordinary gin, however, cannot be successfully used in separating the lint of sea island cotton from the seed. The machinery generally used for this purpose consists of two fluted rollers, commonly made of wood, but sometimes of vulcanized rubber or steel, about ⅝ in. in diameter and from 9 to 16 in. long, placed parallel in a frame which keeps them almost in contact. These rollers, revolving in opposite directions, draw the cotton between them, while the seeds are prevented from passing by the want of sufficient space. This machine is worked by the foot of the operator acting upon a treadle, while the cotton is fed between the rollers by hand. From 30 to 40 lbs. a day can be cleaned by one of these machines, while the average daily capacity of an ordinary Whitney gin is about 3,200 lbs. Horse power is commonly used in ginning cotton; but on large plantations steam is used.



The next process is that of packing the cotton into bales. This is