he paper is now !male, and only requires finishing. The greater number of the finishing processes are only required for writing-paper : common printing-paper and wrapping-papers being ready for packing imp when dried. 1Vnting-paper is dipped, fire or six sheets together, into a tub of size, and afterwards pressed to force out the superfluity. It is then hung up again in the drying-room. Printing-paper is sized In the stuff. Every sheet is examined, imperfections are removed, and had sheets takeu out. A largo pile of paper is then made, and pressed with great force to render the sheets quite flat and antooth. The pile is next taken down sheet by sheet, and another made, by which new surfaces are brought Into contact with each other ; and the pile is again pressed strongly. This operation, which is called parting, is done two or three times for the best papers. The paper is now counted into quires, folded, and packed up into reams. The size is made from skins and other animal substances, and is required to prevent the ink from spreading among the fibres by capillary attraction. Blotting-paper is not sized.
Wo now proceed to notice the machine-method of making paper— without which, the extension of cheap literature, and the wonderful development of the newspaper system, would have been almost hnpos Able; printing-machines would possess insufficient material to print upon, had not paper-making machines kept pace with them. The history of these last-named machines is briefly as follows. Just at the close of the last century, M. Robert, a workman in the employ of M. Francois Didot, at a paper-mill at ESSOIICA, in France, invented a machine for making continuous paper ; Didot set the apparatus to work ; and Robert obtained 8000 francs from the government, and a patent for fifteen years. This was in 1799. In 1801 Didot came over to England, accompanied by Mr. John Gamble, who had resided some time in France. After sundry negotiations, and the obtaining of two English patents, these patents were sold to Messrs. Fourdrinicr. Messrs. Hall's establishment at Dartford, in Kent., was selected as the place for making the machines, under the special care of Mr. Bryan Donkin. It was in 1803 that the model of the first self-acting machine was set up at Frogmore, in Hertfordshire; and in 1804 that the system came successfully into work at a paper-mill at Two Waters. Since that year, a succession of beautiful additions and improvements have been made; although it is only just to mention that the main principles of the machine have all along remained nearly the same. Messni. Bryan Donkin & Co. have devoted such special attention to this sub ject., that they have throughout been the chief makers of the machines: in the first ten years they set up 13 paper-machines ; in the next ten, 25; by the year 1851 they had set tip 191 ; and the number has since steadily increased. So far from these having all been intended for home use, more than half were made for foreign manufacturers : Germany being the best customer on the continent. of Europe. It is proper to state that some of the matters connected with the early history of the paper-machine, both as to honour and profit, are still in dispute; and that so late as 1857, Mr. John Gamble, in a communica
tion to the Society of Arts, protested against the way in which his name is generally omitted from among those who deserve credit or fame as introducers of the paper-machine. It is not often that an inventor, or the fosterer of an invention, lives to put in such a claim fifty-six years after the occurrences to which the claim relates.
We shall now briefly describe the operation of the paper-machine. The machine is constructed in such a manner as to imitate, and in sonic. respects to improve, the processes used in, making paper by hand ; but its chief advantages are, that paper can be made of any size that can practically be required, and with a degree of rapidity which leaves the other mode of making it at an immeasurable distance. The pulp is first made to flow from the vat upon a wire frame, or sifter, which moves rapidly up and down so as to force the fine filaments of the pulp through the wire, whilst it retains any knots or other unsuitable matter. Having passed through the sifter, the pulp flows over a ledge iu a regular and even stream, and is received upon an endless web of wire-gauze, which presents an uninterrupted surface several feet long. The wire-web moves forward with a motion so regulated as, taken iu connection with the quantity of pulp allowed to flow upon it, to determine the thickness of the paper. At the same time a shaking motion is given from side to side, to the wire Web, which assists in spread ing the pulp evenly, and also in facilitating the separation of time water, which passes through the wire ; by this means the pulp solidifies as it advances, and is at the same time prevented from flowing over the sides by straps which regulate the width of the paper. Before the pulp, now no longer fluid, quits the plane of wire, it is pressed by a roller covered with felt. It is next taken up by an endless web of felt, which forms an inclined plane, and gradually moving forward absorbs a further portion of the moisture. The pulp is now seized by a pair of rollers, between which it is pressed; and then it passes upon another inclined plane of felt, which conducts it to another pair of pressing rollers. The pulp is at length paper, and only requires to be made dry and smooth. To effect these objects, the machinery conducts it over the polished surface of a large cylinder heated by steam. From this cylinder it passes to a second, larger and hotter, and then to a third, which is still hotter than the second. After this it is subjected to the pressure of a woollen cloth, which confines it on one side while the cylinder smooths it on the other. It is then conducted by another roller to a reel, on which it is wound, perfectly dry and smooth, and ready to be cut into sheets for use. In two or three minutes the pulp, which is introduced upon the wire web at one extremity of time machine, is delivered at the other in the state of perfect paper. In printing-paper the size is commonly added to the pulp ; but writing paper is sized after the sheets are cut, as in hand-made paper.