trees or plants, which are still usually known by the Latin name of arbors; as the arbor Dianæ, or SILVER-TREE; arbor Martis, These expe or IRON-TREE; and arbor Plumbi, or LEAD-tree, riments are simple as well as curious and entertaining, and we shall, therefore, subjoin the following as the easiest processes for working them.

Silver Tree.-Arbor Dianæ.

appear

In this experiment the branches and figure of a tree are reprewhich mercury, sented by an amalgam of silver and to vege tate in a very beautiful manner. To obtain it, one part of silver, dissolved in nitrous acid to saturation, is mixed with twenty parts of clean water, and poured upon two parts of mercury. When left standing quietly, the desired crystallization will take place after some time. A cylindrical glass vessel is best suited for the purpose; and that the process may succeed, it is necessary that the ingredients be in their utmost purity.

Iron Tree.-Arbor Martis.

An apparent vegetation of iron, resembling a natural plant. It is formed by dissolving iron filings in diluted nitric acid, and adding to the solution a quantity of carbonate of potash in a deliquescent state, or what was formerly called oil of tartar per deliquium. The mixture swells considerably, and is no sooner at rest than the branches spring out on the surface of the glass.

Lead Tree.-Arbor Plumbi.

Is a beautiful vegetation of lead. To form it, two drams of acetite of lead (sugar of lead) are dissolved in six ounces of distilled water; the filtered solution is poured into a cylindrical glass, and a thin roll of zinc being hung in it, the whole is left standing at rest. The lead precipitates, adhering to the zinc in metallic leaves, in the form of a tree.

THE

GALLERY

OF

NATURE AND ART.

PART II.

ART.

BOOK IV.

POLITE ARTS, or those connected with LITERATURE.

CHAP. I.

PAPER MAKING.

PAPER

APER is well known to be a thin flexible leaf, usually white, artificially prepared of some vegetable substance, chiefly to write upon with ink.

The word is formed from the Greek παπυρος, papyrus, the name of an Egyptian plant, called also βιβλος, biblus, whereon the ancients used to write.

Various are the materials, on which mankind in different ages and countries have contrived to write their sentiments; as on stones, bricks, the leaves of herbs and trees, and their rinds or barks; also on tables of wood, wax, and ivory; to which may be added plates of lead, linen rolls, &c. At length the Egyptian pa. pyrus was invented; then parchment, then cotton paper, and lastly, the common, or linen paper.

In some places and ages they have even written on the skins of fishes; in others, on the intestines of serpents; and in others, on the backs of tortoises. Mabill. de Re Diplom. lib. i. cap. 8. Fabric. Biblioth. Nat. cap. 21, &c. There are few sorts of plants but have at some time been used for paper and books: and hence the several terms, biblos, codex, liber, folium, tabula, tillura, philura, scheda, &c. which express the several parts on which they were written: and though in Europe all these disappeared upon the introduction of the papyrus and parchment, yet in some other countries the use of divers of them obtains to this day. In Ceylon, for instance, they write on the leaves of the talipot. And the Bramin MSS. in the Tulinga language, sent to Oxford from Fort St. George, are written on leaves of the ampana, or palma Malabarica: Hermannus gives an account of a monstrous palm tree called codda palma, or palma montana Malabarica, which about the thirty-fifth year of its age rises to be sixty or seventy feet high, with plicated leaves nearly round, twenty feet broad, wherewith they commonly cover their houses, and on which they also write, part of one leaf sufficing to make a moderate book. They write be. tween the folds, making the characters through the outer cuticle. Knox. Hist. Ceyl. lib. iii. Le Clerc. Bibl. Un v. tom. xxiii. p. 242. Phil. Trans. No. 226, p. 422, seq. Vide Hort. Ind. Malab. p. 3. Phil. Trans. No. 145, p. 108.

In the Maldive islands, the natives are said to write on the leaves of a tree called macaraquean, which are a fathom and a half long, and about a foot broad. And in divers parts of the East Indies, the leaves of the musa arbor, or plantain-tree, dried in the sun, served for the same use.

Egyptian paper was principally used among the ancients; being made of the papyrus, or biblus, a species of rush, which grew on the banks of the Nile: in making it into paper, they began with lopping off the two extremes of the plant, the head and the root: the remaining part, which was the stem, they cut lengthwise into two nearly equal parts, and from each of these they stripped the scaly pellicles of which it consisted. The innermost of these pel. licles were looked on as the best, and that nearest the rind the worst: they were therefore kept apart, and made to constitute two different sorts of paper. As the pellicles were taken off, they extended them on a table, laying them over each other transversely, so that the fibres made right angles: in this state they were glued together by the muddy waters of the Nile; or, when those were not to be had, with paste made of the finest wheat flour, mixed with hot water and a sprinkling of vinegar. The pellicles were next pressed, to get out the water, then dried, and lastly flatted and smoothed, by beating them with a mallet: this was the Egyptian paper, which was sometimes further polished by rubbing it with a glass ball, or the like.

Bark paper was only the inner whitish rind, inclosed between the bark and the wood of several trees, as the maple, plane, beech, and elm, but especially the tilia, or linden-tree, which was that mostly used for this purpose. On this, stripped off, flatted, and dried, the ancients wrote books, several of which are said to be still

extant.

Chinese paper is of various kinds; some is made of the rinds or barks of trees, especially the mulberry-tree and elm, but chiefly of the bamboo and cotton-tree. In fact, almost each province has its several paper. The preparations of paper made of the barks of trees may be instanced in that of the bamboo, which is a tree of the cane or reed kind. The second skin of the bark, which is soft and white, is ordinarily made use of for paper: this is beat in fair water to a pulp, which they take up in large moulds, so that some sheets are above twelve feet in length: they are completed by dipping them, sheet by sheet, in alum water, which serves instead of the size among us, and not only hinders the paper from imbibing the ink, but makes it look as if varnished over. The paper is white, soft, and close, without the least roughness, though it cracks more easily than European paper; is very subject to be eaten by the worms, and its thinness makes it liable to be soon worn out.

Cotton paper is a sort of paper which has been in use upwards of six hundred years. In the grand library at Paris are manuscripts on this paper, which appear to be of the tenth century; and from the twelfth century, cotton manuscripts are more frequent than parchment ones. Cotton paper is still made in the East Indies, by beating cotton rags to a pulp.

Linen or European paper appears to have been first introduced among us towards the beginning of the fourteenth century, but by whom this valuable commodity was invented is not known. The method of making paper of linen or hempen rags is as follows.

The first instrument is called the duster, made in the form of a cylinder, four feet in diameter, and five feet in length. It is alto

gether covered with a wire net, and put in motion by its connexion with some part of the machinery. A convenient quantity of rags before the selection are inclosed in the duster, and the rapidity of its motion separates the dust from them, and forces it through the wire. It is of considerable advantage to use the duster before se. lection, as it makes that operation less pernicious to the selectors.

The selection is then to be made; and it is found more convenient to have the tables for cutting off the knots and stitching, and for forming them into a proper shape, in the same place with the cutting-table. The surface, both of these and of the cutting.table, is composed of a wire net, which in every part of the operation allows the remaining part and refuse of every kind to escape.

The rags, without any kind of putrefaction, are again carried from the cutting table back to the duster, and from thence to an engine, where, in general, they are in the space of six hours reduced to the stuff proper for making paper. The hard and soft of the same quality are placed in different lots; but they can be re. duced to stuff at the same time, provided the soft is put somewhat later into the engine.

The engine is that part of the mill which performs the whole action of reducing the rags to paste, or, as it may be termed, of trituration. The number of engines depends on the extent of the paper-work, or the force of water, or on the construction of the machinery.

When the stuff is brought to perfection, it is conveyed into a general repository, which supplies the vat from which the sheets of paper are formed. This vat is made of wood; and generally about five feet in diameter, and two and a half in depth. It is kept in temperature by means of a grate introduced by a hole, and surrounded on the inside of the vat with a case of copper. For fuel to this grate, charcoal or wood is used; and frequently, to pre. vent smoke, the wall of the building comes in contact with one part of the vat, and the fire has no communication with the place where they make the paper.

Every vat is furnished on the upper part with planks closed in. wards, and even railed in with wood, to prevent any of the stuff from running over in the operation. Across the vat is a plank which they call the trepan, pierced with holes at one of the extre. mities, and resting on the planks which surround the vat.

The forms or moulds are composed of wire cloth, and moveable