Page:Willich, A. F. M. - The Domestic Encyclopædia (Vol. 3, 1802).djvu/361

339&#93; PAP it is conveyed to the vat, and worked in the manner praftised with linen rags. In the year ISO I, a patent was granted to Mr. Koops, tor extract- ing ink from printed paper, and restoring it to its original state. — His process varies little from th:it above described ; the paper being agitated in hot water, to extract the size, and reduce it into a pulp : next, the adhesion of the ink is to be removed by a caustic alkali pre- pared of lime and pot-ash, thequan ■ titles of which, should be propor- tioned to those of the paper. After discharging the ink, he Jire.6ls the pulp to be bleached by means of the oxygenated marine acid, in the proportion of 10 or 12 gallons to 140lbs. of the material; and, when sufficiently whitened, it is re-manufa6^ured in the usual man- ner. — According to the patentee's account, w'/-i/z"«^ paper docs not recjuire so large a proportion, if any, of the caustic alkali ; but is bleached by contining it in a wooden box, rendered air-tight ; into which the acid gass is thrown diredly from the retort wherein it was pro- duced. The staining, or dyeing of paper, is pertbrmed by applying, with soft brushes, any of the colours used for tinging other substances, after tempering ihem properly with size or gum-water. Should the papei not be sntFiciently hard to receive the tint without sinking, it will lirst be necessary to si"^'- it, or to employ a larger proportion of gum with the tinging matters. And, if the paper is to be of an uniform colour, tiie latter must be fixed by several thin coatings, each being sutiered to dry, before another is applied ; as the shcida will otherwise appear unequal. PAP [339 As writing paper is often im- perfectly si%ed, in conscijuence of which the ink is apt to sink, it has been recommended to dissolve a small piece of Roman alum in a glass of pure water. This liquor should be gently spread over the suspefted part, with a soft sponge ; and, after becoming dry, it may be safrly used for writing. — Should there be any occasion to write on a printed book, or on paper that is loo fresh and moist, it will only be nvcessary to mix a little gum with the ink.— Lastlv, in case anv book or manuscript be stained with oil, or grease, it has been direfted to calcine and pulverize the bones of sheep's trotters ; and to apply 3 small portion of the powder to each side of the stain, which should be placed between two sheets of white paper, and the whole submitted for the space of twelve hours to the action of a press : if the stains do not disappear, the process should be repeated in a warm place. Various patents have been grant- ed for inventions, or improvements, in the dilTcrent branches of tiie pa- per-man ufaC'ture ; but, as the speci- fication of them would benvtit only a small part of our readers, we shall not t-nter into particulars :■ — the J'ollowing, however, deserve to be noticed, namely : Mr. Hooper's, in 1 7^7 > ^<^f i'lis invention of a paper fur printing; and, in 17Q0, tor making paper of difterent sorts from leather-cuttings ; — Mr. CuNTNlNG- HAJ.i's, in 179'ij for manufa6turinj^ paper from various materials 3— Mr. Bigg's, in 1/95, for a cheap and expeditious mode of bleaching' paper; — and Mr. CAEPENTiiR's patent, obtained in the same year, tor a new method of bleaching in the water-leaf or sheet, Papek-Hangings^ are a parti- Z 2 cular