The line shaft is carried directly under the gins where all of its journals are in sight; it can be easily oiled and hot-boxes instantly de tected. At the end of the row of gins a higher platform is built to surround the press. Bales are taken out on this platform and can be thrown into the wagons thence without further expenditure of labor. After the mechanical processes of by the exhaust fan and dropping the cotton into each gin, blowing it from the gins to the presses and its packing there by a steam tramper, the operation of put ting on the bagging and tying the hoops is the first manual labor necessary after the feeding from the wagon into the telescope.
The principal machines used in a modern cotton ginning establishment, in the order in which they are used, are the telescope, the elevator, the exhaust fan, the feeder, the gin, the seed conveyer, the flue, the condenser and the press.
The telescope is an extensible tube which hangs from the inlet cotton pipe; it is counter balanced and so arranged that its tube can be pulled down and kept close to the pile of cotton as it decreases in size. A pneumatic elevator is the apparatus generally used to distribute cotton to the gins. In a system using four gins each valve is open a fourth of the time and closed three-fourths. When the first air valve in the first chute is open a vacuum is formed in the chute, the outside air, carrying with it the cotton, rushes in from the telescope. The air is drawn through the screen into the fan, while the cotton strikes against the screen with enough force to take out a large part of dirt and dust, no cotton being ever allowed to get into the blades of the fan on account of the danger of fire. By shifting the valves another chute is opened and the stream of cotton and air is deflected to the second chute, and the cotton in the first dropped from the screen and into the feeder below.
The feeder, which is over the gin, has for its object the cleaning of the seed cotton, break ing up the lumps and then feeding the locks evenly and regularly into the gin. A slowly moving apron receives the cotton from the elevator and carries it to the picker wheel. This wheel, revolving with great rapidity, picks up the locks of cotton and throws them against the screen. The particles of dirt and trash go through this screen and are carried away by a helical conveyer. The cotton is rubbed over the screen and thrown on an inclined apron, which carries it into the roll boxes of the gins.
The flue which conducts the cotton from the gins is made of sheet metal and shaped like a long funnel with the larger end near the con denser, which is located at the end of a flue and acts as a collector of the bunches of cotton that fly through the flue like snow and makes them into a bat or sheet of cotton. This bat
of cotton drops down an incline into the press.
The press used in the square bale system of gins consists of two boxes mounted together on a turntable. Cotton from the condenser is allowed to drop into the first box and when enough cotton has been forced into it by the steam tramper, the turntable is revolved and the other box comes in its place. The loaded box comes into position over a ram where it receives the final pressure. This ram is oper ated by a large direct-acting steam cylinder, a hydraulic ram, or a screw which is raised and lowered by a revolving nut. The bales turned out by this square press usually weigh 500 pounds gross, and average 28 x 56 x 42 inches in size and thus have a density per cubic foot of about 14 pounds. They are usually shipped from the gin house to some concentrating point where they are assorted and compressed, and their size is reduced to 28 x 56 x 18 inches, giv ing them a density of 30 or more pounds per cubic foot. They are then ready to be shipped to the cotton mills.
The large compressers which do this pressing are enormous machines weighing in some cases as much as 200,000 pounds, and are operated either by direct-acting steam cylinders coupled to the jaws of the press by multiplying levers, or the jaws of the press are brought together by a large link moved by hydraulic rams sitting directly over the press. The capacity of this press ranges from 800 to 1,200 bales in 10 hours. The bales while in the press are recovered and their bands are shortened to suit the reduced bulk.
Early in the present century the American Cotton Company developed a cylindrical bale, which permitted the cotton to be compressed more tightly and therefore to occupy less space in a freight car. A bat or layer of cotton is formed, rolled down very hard and wound up on itself, or rolled together under pressure and tension so that it forms a cylinder and tends to hold itself together. The square bale when compressed to more than 60 pounds to the foot required heavier bands or else it was apt to burst; but the cylindrical bale makes use of the cotton itself to hold it in place. It is simply wound up very tightly and tied, taking very readily a pressure of 35 to 40 pounds to the cubic foot. This bale is made in a bat-forming and condensing machine, and is usually made smaller and hence considerably lighter than the so-called square bale. This cylindrical bale has the advantage that it arrives at the cotton mill conveniently protected by bagging hav ing neither wires nor hoops, and there is less tear and waste; it is also cheaper to manufacture.