Mr. Herring, in a recent work on the paper manufacture, while giving a list of the various sizes and names of paper, puts together the writing, drawing, printing, and wrapping papers, and then separates them simply into two groups, according as they are fine or coarse. The chief names and sizes mentioned by him are as follow :— So numerous, however, are the sizes, thicknesses, and qualities of the various kinds of paper, cardboard, millboard, &c., that some of the largest wholesale dealers, according to Mr. Herring, keep in stock not much less than two thousand different kinds. Placing them under a few headings, without regard to size, papers are sometimes designated thus :—IVriting paper, five kinds, namely, cream wove, yellow wove, blue wove, cream laid, and blue laid ; printing paper, two kinds, namely, laid and prove; wrapping paper, four kinds, namely, blue, purple, brown, and whited-brown. In these various kinds of paper it is believed that England takes the lead of the Continent, except in two particulars : that thin French writing-paper is better than English ; and that the French obtain a purer surface than the English, who often hide a dirty white by blueing it A few years ago careful experiments were made to determine the relative atrengtha of different kinds of paper ; and the result was given in the last edition of the ' Encyclopmdia Britannica.' In the following table the first column shows the kinds of the paper ; the second, the weight in grains of a superficial foot; and the third, the weight in pounds upheld without. breaking by a strip two inches broad :— Among the varieties in paper-making may be mentioned Dickinson's double-faced paper, to be used either for lithographic or copper-plate printing, according as one or the other surface is selected; two webs of different kinds of pulp are placed one on another, and are pressed so as to unite them into a single sheet. Laced paper is now very much employed. The French have long made it, and applied it to orna menting fruit-baskets, lamp-shades, print-borders, &c. About 1830, 31. Itiviere, a Swiss watchmaker established in London, obtained a patent for perforating thin metal platen ; Messrs. De la Rue contrived a modification of the same apparatua for perforating pasteboard and card ; and hence has arisen an extensive branch of ornamental paper making, especially for valentines, the production of which is enormous. Plain-surface coloured papers are now largely made, for the use of bookbinders, printers, button-makers, confectioners, &c. The colour is applied by means of brushes, similar to those employed by paper stainers ; but the pigments are better, and more care is taken in laying on, smoothing, and finishing. Gilt, silvered, and coloured papers are prepared for decorative stationery, by chromolithography, surface-printing, block-printing, and woven-wire printing. The inge nuity of paper-makers has also been directed to the production of paper covered with real gold and sivcr; paper coated with bronze or imitation bronze ; paper embossed and grained by means of engraved rollers, dies, and plates ; paper varnished to imitate Morocco leather ; paper enamelled, for the ground of fine satin paper-hangings, and for other ornamental purposes, by treating the surface with sulphate of barytes—a pigment reduced in price within a few years from 21s. to 6d. per lb. • paper extra•enamelled with Kremuitz white lead, for wedding•esrds, &c. ; paper with an opaline iridescence, prepared by licasrs. Da la Rue ; paper to which a kind of metallic granular surface has been given, for memorandum books ; &c.
Much attention has been paid to the manufacture of paper which nay frustrate the designs of forgers. The selection of a device or design for bank.notea. cheques, &a the nieste of engraving. the mode of prusting, and the kind of Ink, all bear immediately ou this subject.
The principle I. thle—to apply to the paper ouch a chemical agent that, sf the Ink be tampered with, the paper shall become discoloured and the attempt at fraud revealed. Mr. Stone, Mr. Barclay, Mr. Stevenson, Mr. llerapath, and other persons, have directed their attention to this matter; anti the chemicals 'suggested for application are te of potash, Iodide and frrrocyanlde of the Name alkali, salts of copper, salts of manganese, starch, &a One recipe is, for a ream of poet, 1 cu. of Iodide of potash, I at. of ferrecisuitle of potash. and 1 lta. of starch. Any attempt to remove writing by chemical agents from paper thus treated would damage the colour of the paper Itself A paper has been read and a discussion has taken place on this subject before the Society of Arts during the pnaent year 11860).
Of the practical application, of paper little need be paid : these are for the most part sufficiently obvious. The amateur arts of papyro usrhY, papyn.plastn, letichomanie, kc., ere little more than inge nious moles of cutting out sheets of paper. We may mention, however, the bituminisal paper totem mule by M. Jaleureau. He finds that whets bitumen is mixed with chalk, and paper tubes are saturates] with it, they become remarkably strong and durable, and are available as waterinpes.
Materiels for Paper—A little attention must now be paid to the subject of the materials for paper, concerning which the manufacturers have lately had many discussions. Repeated attempts have been inade to manufacture paper from straw, but it is only recently that any sun :sees has been obtained. One mill in the United States now makes 30 tons of this paper weekly. Wheat-straw is put into a large spherical boiler, and there boiled for 24 hours at 320' Fahr., a temperature obtained under great pressure. The straw becomes con verted into a glutinous mass, which by further processes is available OA pulp for paper. Dr Collyer, in April, 1860, communicated to the Society of Arts the result of an elaborate series of experiments on the manufacture of piper from straw. He was led by his researches to recommend the following processes :—The straw is first passed between two rollers rotating with different velocities ; this produces a trituretory action, which rubs out the knots and ears, and at the same time opens the straw out to a partially fibrous Mete. The straw is then exposed to the action of water heated by steam, and containing 3 ors. of caustic alkali to the gallon. The apparatus is so arranged that the alkaline liquor can act over and over again upon the straw; and by repeated workings after this steeping, nearly all the gluten and silica are removed from the straw. The bleaching is effected by chloride of lime, with superheated steam. The making into pulp then Clones, and the manufacture proceeds as with rags. These operations, however, are quite tentative. All the straw paper hitherto made is unpleasantly crisp and brittle ; and it has been found that the price of straw goes up considerably whenever the paper-makers create a demand for it. Nevertheless, two or three of the penny daily newspapers are printed on straw paper, and the experiment is felt to be worthy of further investigation.
Another kind of paper is Schlesinger's, manufactured of wood. Timber is cut by machinery into logs about eight inches in length. These logs are made to press against a rotating grindstone made of very rough atone, and well moistened with water. The wood is rubbed off in a state of fibrous pulp, which, either used by itself, or mixed in certain proportions with rags, is converted into paper. A mill for the manufacture of paper of this kind was opened at Bradford in 1854, the paper produced being chiefly wrapping, packing, cartridge, and other coarse kinds. The stood pulp is said to be obtainable at about hi. per pound.