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been made into a white pulp, some of this pulp is taken up upon the mould, which is a level frame with a wire bottom, through which the water drains off from the pulp. The pulp is kept on the mould by the deckle, a hollow wooden frame, which fits upon it. The mould is then shaken until the pulp becomes of sufficient consistency to be removed, when it is placed between two pieces of felt, and pressed. After this, the sheets are taken from between the felt, and pressed by themselves. They must then be separated and turned, and again put together and pressed; and this process repeated until the paper is sufficiently smooth. In this way much of the water is squeezed out; but the sheets must be further dried by being hung up separately in the drying-room for some days: they are then collected and pressed again before being folded into quires.
In the paper-machine the place of the mould is supplied by a cloth of fine wire,* doubled in the form of a jack-towel, and passing over rollers attached to a frame; the wire-cloth is usually about five feet wide and twenty-five feet long. Instead of the deckle, there are narrow strips of india-rubber, or gutta-percha, which form a raised edge on each side of the wirecloth: these are called deckle-straps. The pulp flows through a kind of trough from the vat to the wirecloth. By means of an arrangement of wheels, the frame is shaken quickly to and fro at the same time that the wire-cloth moves on round the rollers. The deckle-straps keep the pulp from flowing away, while the water drains through the wire, and the pulp being shaken together, acquires a certain degree of
* This wire contains about 3600 holes in the square inch.
consistency as it is carried along, and is rendered still firmer by the pressure of two rollers covered with felt, between which the wire-cloth passes with the paper upon it. When the wire-cloth turns back, the paper leaves it, and is taken up by an endless felt moving upon rollers. This felt conveys the paper to two iron cylinders,* where it receives a great pressure. From these it passes to a second pair of rollers, and is still more pressed. The paper, which is still very damp, is now carried by another roller to a large iron cylinder, heated within by steam; from this it passes to another cylinder still hotter, and once more to a third, which is the hottest of the three. All moisture and roughness of surface have now disappeared, and the paper is finally wound upon a reel, and when a certain regulated quantity is collected, is cut off from the machine, and a new reel placed to receive a fresh supply. From the moment when the liquid pulp is flowing from the vat, to the final completion of the beautifully-polished white paper upon the reel, scarcely two minutes elapse. This result in the ordinary state of the weather could not formerly have been obtained in less than seven or eight days. The machine moves at the rate of from 25 to 40 feet per minute. If the machine makes a length of web equal to ten yards per minute, it produces 600 in the hour, or 4 miles per day of 12 hours. It is reckoned that in Great Britain there are 300 machines at work every day; so that upwards 370,000 miles of paper, about five feet wide, are made every year. This quantity of paper would cover about 200,000 acres.
Cylinder means roller.
Paper-mills are generally worked by water, which is sufficient for this purpose, and involves less expense than steam; but steam is also made use of in papermills, as well as in other works where no other moving power would suffice.
THE USE OF MACHINERY.-PART II.
THE PRINTING MACHINE, AND SPINNING MACHINE. If we had not such a force as steam at our disposal, very little of our present machinery would have been invented; indeed, without steam it would be useless, for no other power would be strong enough to set it in motion.
Besides this, we could never produce with our hand the regularity of motion, which is one of the main requisites in machinery.
Again, since we can thus bring an enormous force to bear upon a particular point, machines can be worked with a speed perfectly marvellous, if we compare it to what can be done by hand. One of the most striking examples of this is the printing-machine. After the types have been set up in what is called the form, they must be inked, and then a sheet of paper being placed upon them, must be pressed down with great force. In the original press all this was done by hand. Various improvements were introduced to
*See Lesson 30.
lessen the labour of pressing and to make it more
In the printing-machine, steam is employed, and we have therefore no difficulty in obtaining any amount of pressure that we desire. By the aid of most ingenious contrivances, the same force which moves rollers to ink the types carries the sheet to the types, presses it upon them, and after one side has been printed, conveys it forward to other types to be printed upon the other side. So long as the machine is in good order, all that is required is the assistance of a workman to feed it by placing sheet after sheet of blank paper upon that part of the machine where it is taken in.
Before the printing-machine was employed, it required two presses and six men to print 350 copies of the Times newspaper in an hour. The paper was then only half its present size. The Times is now printed by a machine, which is capable of producing with ease 10,000 copies in an hour.
There is a still more important application of machinery than this. All the common materials of our dress are formed by weaving-that is, by twisting together in various ways threads of linen, cotton, or wool. The weavers' hand-loom is one of the most ancient of all machines. But before the loom can work, the threads must be prepared. Less than a hundred years ago the only way of preparing these threads was by the spinning-wheel, and with this wheel it was scarcely possible for one person with the greatest industry to produce a pound of thread a day. This thread, or yarn, as it is more properly called, was mostly spun in the cottages of the peasantry, and
gave abundant occupation to the female members of every poor family. But as there was more and more demand for woven goods, looms were often at a standstill for want of yarn, which the weaver found it difficult and sometimes impossible to procure. This want led ingenious men to devise Spinning Machines, which, after various inventions and improvements, have been brought to an astonishing degree of perfection. Besides all the different kinds of cloth, linen, and calico, and such substances used in our own country, we export every year an enormous quantity of these manufactures. Our spinning machines provide us with yarn for all such goods; and, besides, we are able to part with a very considerable amount of yarn itself. The quantity of cotton-yarn spun in England and Scotland in 1845 was 494,766,487 lbs., of which 131,937,935 lbs. were exported.
THE USE OF MACHINERY.-PART III.
COTTON-YARN-EFFECT UPON LABOUR.
We have mentioned only machines for spinning; but much must be done before the raw material is reduced to a fit state to be spun. Cotton, for instance, grows in a pod of a plant chiefly cultivated in America:-1, the pods must be gathered; 2, the wool must be separated from the husks and seeds. This is done before it is packed and sent to England. After its arrival in this country it must (after having been sorted) be-3, willowed, a process