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method of taking off impressions: 5, of the uses to which this art may be put.
First then of the stone. The properties required, are, that the stone employed shall bear a tolerably smooth, and perfectly uniform surface; free from any heterogeneous veins or specks, when it has been rubbed down with sand, and then with emery, to the fineness of the surface of glass, roughed for shades or moonlights; or a little finer. It must have just roughness enough and no more, to catch hold of the crayon, and take the mark of the drawing: hence, although smooth, it must not be polished. Another property is, that when dry, it shall imbibe on its surface a sufficient quantity of water, to become so moist that a greasy or oily substance, will not adhere to the moist part of the stone: but it is not necessary that it should contain any argillaceous matter; the stone from whence Mr. B. Otis took the impression in question, is purely calcareous, dissolving without residuum in marine or muriatic acid. The stone should be at least two inches, or rather two and a half inches thick, to bear the force of repeated pressure in taking off the impressions. The stone used at Munich and at Paris, is a secondary or floetz , limestone; probably a member of the lias limestone, being the white calcareous flagstone that covers the blue lias; there is hardly any difference in appearance, in quality, or in properties, between the Munich and Parisian stones, and the limestone of Kentucky; as was first suggested by Mr. Clifford of Kentucky, at judge Cooper's mineralogical lectures, and as has been proved by the experiments of Mr. Otis.
The Parisians make two imitations of, or rather substitutes for the genuine stone; one, by means of finely sifted, well burnt, white plaister of Paris or alabaster, mixed up with water, in which some alum has been dissolved—and another, when they wish to transfer writing to the stone, 'In the latter case, they proceed thus: thick smooth paper is prepared with gum arabic, and a little finely powdered and sifted chalk or whiting. This is written upon with the crayon, and immediately before it is dry, transferred to the stone, which then furnishes an impression in the natural order of the writing. Whether plaister of Paris itself would answer the pur-, pose, has not yet been tried. The limestone near Maystown, is a yellowish white stone of the transition formation.
The stone being thus prepared, smooth but not polished, the proposed design is traced upon it, either by liquid ink, or solid crayon.
Secondly, of the ink and the crayon. The German receipt for the ink is as follows:- Take white soap of the best kind, one part by weight; mastic in drops one part: melt them slowly and carefully together, in a glazed earthen vessel; then add, shell lac by weight five parts, and continue to stir the mixture over the fire. Then add, by degrees, to prevent boiling over, one part of pure or caustic soda (or potash deprived of its carbonic acid), dissolved in six parts of pure water; stirring the mixture at each addition, to
prevent its boiling over. Let the heat be moderate, and add grad. ually of lampblack, burnt over again in a covered crucible, enough to colour the mixture. Draw your design, with a common or crowquill pen, or a fine pencil, as it may require, and let it remain for at least 24 or 30 hours, to dry.
There are various receipts for the composition of the crayon: the common German receipt is this
Take of fine white soap three parts; purified tallow two parts; white or yellow wax, one part: melt them together, and add sufficient of burnt lampblack to give the necessary colour and consistence. Run it while hot and fluid, into moulds the size of a common crayon. If too soft, so that you cannot cut it down to & sufficiently fine point, lessen the quantity of soap and tallow, or add a little black pitch, or mastic.
With the ink, or the crayon so made, trace your design on the stone. Let it remain for 24 or 30 hours, till it be dry. Then cover the surface of the stone with water, which will be imbibed sufficiently in all the parts of the stone untouched by the drawing, to prevent its being affected by the engraver's ink, used to take the impression: engraver's ink seems better for the purpose than printer's ink; the lampblack collected from the burning of wax or good oil, and afterwards burnt in a close crucible for half an hour, is best.
The engraver's ink is then dabbed on the stone with printer's balls, and adheres only to the greasy marks of the drawing; for the moist part of the stone does not receive any impression,
The Germans take the impression on paper, by means of a wooden roller, wrapped round with buff leather, and attached to the end of a long stick, of which the other end is attached to a beam in the ceiling; a motion backward and forward, suffices to take the impression, which is not good till about a dozen are taken. Ten or twenty thousand may be taken from one drawing.
If the impression is meant to be strong, you let the drawing remain for a day or two till dry; and then, putting a border of wax round the stone, pour on it a mixture of one part of nitric acid, mixed with fifty parts by measure, of water; or, one part of muriatic acid to forty parts of water, and let it remain for about 6 or 8 minutes. This liquid acts on the calcareous stone, without touching the greasy drawing, which is thus slightly raised above the surface, and furnishes a more marked and decided outline.
In some cases, the surface of the stone is covered with a varnish of gum-water and lampblack; the design is etched through this varnish, and then the surface is smeared with the ink above described. This ink adheres to the stone in the traces thus etched, and the varnish being washed off in a day or two, the impression remains on the stone, ready to be transferred to paper.
In some such analagous manner, imitations of mezzotinto are produced, as soft as any engraving.
The varnish so used for etching, is harder than the common engraver's varnish: it may be procured of the required softness, by mixing some treacle or molasses with the gum-water. When you wish to displace the varnish, dip the stone edgeways in warm water, till the varnish is loosened. The water must not be too hot, else the greasy trace of the lines will spread and run into each other.
In moistening the stone with water, previous to taking an impression, the surface will be cleaner, if in every case, and in the first instance, about one part of nitric or muriatic acid is added to one hundred parts of water.
If imitations of wood-engravings are wanting, cover the whole stone with the composition ink above described, and when quite dry, scrape away the ink from the parts meant to be white.
The method of taking off the impressions as practised by M. Engelman is as follows. The press consists of a hollow table, terminated at one end by an upright frame, supporting a roller, which by means of a winch may be made to traverse along the table from one extremity to the other. The stone is laid perfectly horizontal in the hollow of the table, and is secured in its place by means of wedges. It is then moistened by means of a sponge, dipped in pure water, till it refuses to imbibe any more. (The first water, as before oberved, should be slightly acidulated, in order to clean more perfectly the surface of the stone, then gently soaked up with the sponge, thrown away, and pure water used). A wooden roller wvered with leather, and charged with very fine engraver's ink, is then passed two or three times over the surface of the stone; the ink adheres to all the lines of the drawing, because, like the ink itself, they are greasy; but it does not adhere to the part of the stone which is moist with water. A sheet of paper, not quite so damp as is required in copper-plate printing, is next laid carefully on the stone; a smooth board is placed above it, and by means of the winch, a pressure is given of about a thousand pounds weight: this is passed slowly over the surface of the board, and the process is finished by removing the board and taking off the impression thus produced on the paper. It is necessary to take a dozen impressions before the work is at its full perfection. Each passing of the roller thus charged with ink, tends to renew the traces on the stone, so that the last print is as good as the first. After a number of impressions have been taken, the stone may begin to be a little blurred. When this is perceived, remove the stone from the press, and pass over it a sponge moistened with oil of turpentine; then wash it with pure water. By this treatment, the whole design will be apparently discharged; but it is not so, for on passing the roller charged with ink, over the surface of the stone, every line, even the most delicate, will again become visible, and the printing may be proceeded in, as at first. For the drawing is left not merely on the surface of the stone, but the ink and the crayon leave a trace that penetrates to a certain depth. Hence the great use of the lampblack is to enable the artist to see his drawing as he proceeds. It also give consistence to the crayon.
I have said that there are several methods of composing the crayons. M. Laugier, having analysed a crayon, such as are commonly used at Paris, found the following substances in the following proportions in it. Wax, 15 parts in 100; wax intimately mixed with grease or suet, 21: suet, 25: mastic or resin, 26: black co. louring matter, 6: loss by adhering to filters, 7: in all, 100 parts.
The ink commonly used, is the engraver's ink, made of nut-oil. The best methods of gathering the walnuts, and making the oil in this country, will be found in Michaux's North American Sylva, p. 146. The method of making with it, ink for copper-plate printing, is to be found in page 148. For light colours, this oil is reduced to two thirds of its bulk; for dark colours, to one fifth, which leaves it a thick semifluid substance. To facilitate the process, one tenth part of linseed oil is added, and it is then placed in an iron or copper vessel, over an active, clear, charcoal fire. When it begins to boil rapidly, the vessel is uncovered, and the oil takes fire, or is set on fire, and permitted to burn to the required consistency. Sometimes it is not allowed to kindle, but when ebullition commences, crusts of bread are thrown in, which collect, and absorb a part of the mucilage of the oil. Linseed oil can be greatly cleared from mucilage, by boiling (which coagulates the mucilage), and cooling; when the mucilage subsides, the oil can be drawn off clear. The nut-oil, thus prepared, preserves its tints longer than linseed oil, and the back of the copper-plate prints do not become brown. Instead of lampblack (which when meant to be used, should be burnt in a red heat for half an hour, in a covered crucible), Frankfort black is commonly employed. This black is made by burning the lees of wine in vessels closely covered.
M. de Lestayrie sells very fine impressions, such as that at the Academy of Arts in Chesnut street, at about 20 francs for twentyfive prints, in Paris.
As to the uses to which this art can be employed, we may ob
1st. It is a perfect fac simile: there can be no mistake or miscopy.
2d. It supersedes all kinds of engraving: when the drawing is finished, it is now sent to the engrayers, and no impression can be taken till the engraving is finished: in lithography, impressions can be taken the instant the drawing is dry, more perfect than any engraving can possibly produce.
3d. It can imitate not only drawings in crayon and Indian ink, but etching, mezzotinto, and aqua tinta.
4th. The plate is never worn out as in copper-plate engraving. In France, 70,000 impressions of a circular letter were taken, before the engraving was finished of a simlar letter written on paper.
5th. Maps, large prints, calico printing, &c. can be executed in this way on rollers of stone, turned, and the design drawn, etched,
or aqua tinted, on the stone roller itself. For roller work in calico. printing, it would be inestimable.
6th. All works of science, may now be freed from the prodigious expense attending numerous engravings.
7th. Any man who can draw, can take off any number of impressions of his own designs, without trusting to any other artist.
8th. The advantage of expedition in the process now recommended, is beyond all calculation.
Art. X.—Sketch of the Life and Literary Character of the late
President Cooper. IN N the sketch of the literary and scientific institutions of the city
of New York, published in the last number of this Magazine, some mention was made of the important services of Dr. Cooper, to the college of New York, and of the active and unfortunate part which he took in the revolutionary contest. As the history and character of this very accomplished scholar are now but little known, out of the city of New York, some further account of him may not be without interest to the readers of the Analectic Magazine.
Myles Cooper, the second president of King's (now Columbia) college, was born in England, in 1735. He was educated at one of the great public schools, and afterwards went to Oxford, where he took the degree of M. A. in 1760, and was soon after chosen to a fellowship
in Queen's college. In this course of education, he. imbibed all the habits, opinions, and tastes of an old fashioned Oxford man, in politics, religion, and literature. In 1761, he published at Oxford, an octavo volume of miscellaneous poetry, which, however, appears to have been written several years before the time of its publication; as he observes in his preface, that the 'greater part of the volume was not only written, but actually printed off before the author had seen the age of twenty-four.' This collection consists of occasional poems, grave and gay pastorals, imitations and translations from the classics, and versifications of select passages of Ossian. It does not appear to me to bear any very strong marks of original poetic genius. It contains no deep views of sentiment or character, nor any strong paintings of external nature. The author, like many other young scholars, seems to have mistaken taste for talent, and a lively perception of the graces of classical composition for the warmth of a poetical fancy. He was by no means blind to the wild and artless beauties of uncultivated nature, yet he recognized them more from comparison with those poetical images with which he had stored his memory, than from the quick sensibility of his own mind. Hence it is, that his poems are filled with traditionary images, and common-place mythological allusions; his wit is too often borrowed from Martial, and his pastorals are faint reflections of the rural scenes of Virgil, Spenser, and Pope—the shadow of a shade.' As a pastoral and