may become a ready means of subsistence. There are few things on which human labour raises the value so highly as wood-engravings. A small piece of wood, worth no more than two or three shillings, may, by a few days of skilful industry, become worth as many pounds. Surely, to be able to impart this high value to an object next to worthless in its raw state, must be deemed no mean talent. The ease with which wood-engraving can be executed within the domestic circle, peculiarly adapts it as an occupation for ladies. On this point we cannot do better than offer the following passages from an article on wood-engraving in the London and Westminster Review' for 1838:- To that large portion of educated gentlewomen of the middle-classes who now earn a subsistence chiefly as governesses, we wish to point out this art as an honourable, elegant, and lucrative employment, easily acquired, and everywhere becoming their sex and habits. We have already done honour to the exquisite delicacy and elegance of the engravings of Mary Ann Williams; we venture to say that few women of taste, whatever their rank in life, can look on "Le Jardin du Paria au lever de l'Aurore" without envying the artist her power of producing a scene so beautiful, and of exciting in thousands the pleasing emotions inseparable from it. Apart from all pecuniary considerations, to be able to do it is an elegant accomplishment; and the study of the principles and details of taste which it implies, is a cultivating and refining process to every mind. All that can be taught of the art may be learned in a few lessons, and thus an acquirement made which will afford no slight protection against misfortunes to which, in this commercial country, even the richest are exposed-and a means of livelihood obtained which, without severing from home, without breaking up family assemblies, is at once more happy, healthy, tasteful, and profitable, than almost any other of the pursuits at present practised by women. The lady we have named is not alone in the practice of this art: we might name also Eliza Thomson, and Mary and Elizabeth Clint, who have furnished excellent engravings for the "Paule et Virginie;" and we have heard of several daughters of professional and mercantile men, not likely to be dependent on their own exertions for support, who have wisely, by learning this art, acquired both an accomplishment and a profession. The occupations, we may also add, are few, indeed, to which gentlewomen of this class can more worthily devote themselves, than to an art which is peculiarly fitted to enhance the enjoyments and refinements of the people, by scattering through all the homes of the land the most beautiful delineations of scenery, of historic incidents, and of distinguished per sons.' ENGRAVING ON COPPER AND STEEL. In the printing of letterpress or woodcuts, as has been already noticed, the impressions are effected by the raised faces of the letters, or marks, in the manner of a stamp. Printing from engraved plates is performed on a principle directly the reverse: in this case the face of the metal, cleared of the ink daubed upon it, gives no representation-the printing is effected from the sunk lines. While wood-engravings may be printed along with type-matter, engravings on plates of metal require to be printed by themselves. The discovery of the art of engraving on metal, for the purpose of making impressions on paper, is generally ascribed to Finiguerra, a goldsmith of Florence. He excelled in an art then much practised in Florence called niello. It was the custom with jewellers, in those times, to engrave the outlines of Scripture subjects upon the vessels which they made for the use of the church. When this engraving was completed, they filled the lines with a black substance composed of a mixture of lead and silver, in solution with borax and sulphur; and impressions were taken from this in clay or sulphur. The black substance used was called niello, and hence the name of the art. The same process was also used when pieces of armour, household plate, and other articles, were engraved for the purpose of being inlaid with metals, wood, or ivory. German writers claim the honour of the invention for a citizen of Antwerp, Martin Schoen gaur, asserting that he practised the art before Finiguerra. It seems probable that it appeared nearly simultaneously in both countries. The earliest distinguished engravers, after the discovery of the art, however, were Italians. It does not appear that Finiguerra pursued his invention any further than to take impressions on paper instead of clay. A contemporary, of the same profession and city, Baccio Baldini, improved upon the invention by engraving on plates for the express purpose of taking impressions on paper. He was greatly assisted by a distinguished painter, Antonio Pollajuolo, who furnished him with designs for his engravings, and also by another artist, Sandro Botticelli, who made a set of drawings, from which Baldini engraved plates for an edition of Dante, published in 1488, and supposed to be the first book ever embellished with copperplate engravings; though this notion has been proved false by a German writer. The works of Baldini attracted the attention of a Roman engraver, Andrea Mantegna, who had already become distinguished as one of the most successful of the niellatori. This artist not only assisted Baldini with original designs, but also turned his own efforts to the promotion of the newly-discovered art, in which he soon became a proficient. In our notice of the early days of the art, we must not omit mentioning Albert Durer, one of the earliest Dutch engravers. Some knowledge of the art seems to have been previously possessed in Holland by Martin Schoengaur, who is thought by some German writers, as we have seen, to have invented it, and who was certainly a contemporary of Finiguerra. The works of Martin, and his disciple Wolgemuth, inspired the genius of Albert Durer, who did much for the improvement of the art, excelling equally on copper and on wood. Marc-Antonio Raimondi, an Italian artist, having seen Durer's prints, improved upon them, and became at Rome a master in the art. Thus the profession was spread simultaneously over Holland and Italy. Although there have been various improvements in the art since this early period of its history, the mode of etching the plates remains substantially the same. At present there are several kinds of engraving practised, each effected in a different manner, and of these we shall now offer a short account: Line-Engraving. This is the principal as well as the most ancient species of engraving. When not executed entirely with the graver and dry point-that is, when the lines are not cut mechanically and finished with the scraper and burnisher-it is commenced by a chemical process called etching. The plate is first cleaned on its polished surface, and heated sufficiently to melt a composition of asphaltum and Burgundy pitch, called etching-ground, which is rubbed upon it, and rendered equal all over, by dabbing with a ball of wool covered with silk. The plate is then held up for the surface to receive the smoke of a wax taper, until it is rendered black and glossy, into which state it comes on not being suffered to cool during the process. These preparations being effected, and the plate becoming cold, the etchingground, which is not thicker than a coat of varnish, is found to be of a hard consistence, and ready to receive the tracing of the subject intended to be etched. The previous preparation of the subject is a very important step in the process. The subject is drawn upon transparent paper with a black-lead pencil, and being laid with the face downwards on the etching-ground, the lines or marks of the drawing are pressed upon it with such force, that they are left on the ground on removing the paper. This is called 'transferring;' and of course the excellence of the representation to be produced depends on the excellence of the drawing. Engravers, therefore, in copying paintings, require to possess a degree of skill in the art of delineation hardly inferior to that of the original artist. The drawing being transferred in the manner described, the engraver applies his tool, or etching needle, over the lines, carefully removing the ground, at the same time pressing sufficiently hard to scratch the surface of the copper. When any error has been committed, the objectionable lines may be stopped out by working a little of the ground over them with a hairpencil dipped in turpentine. When set, the parts so treated resist the aquafortis. A wall of wax is now placed round the margin of the plate, and into the enclosure so formed aquafortis is poured, to the depth of half an inch. This aquafortis decomposes or bites into the copper where the etching-ground has been removed. During this process, globules of air arise from the decomposition, and these are carefully removed with a feather, to allow free scope to the biting liquid. The length of time employed in biting the plate is regulated by the depth required, also by the state of the atmosphere; in ordinary cases, the operation may be performed in about an hour. When it is ascertained that the plate is properly acted upon, the aquafortis is poured off, the wall of wax removed, and the ground cleared with spirits of turpentine. The plate is now said to be etched, and when printed from in this state, exhibits the appearance of a pen-and-ink sketch. To this state of etching, but regulated by the nature of the subject, professional engravers bring the plates to be finished in the line manner. Different gradations of power are given by the aquafortis, and parts are rebitten to the depth required; after which, the light parts are put in with a sharp needle. Other parts are then cut with gravers of various sizes and forms, suited to the lines which will best express the respective objects. The engraver, in thus finishing his work, rests the plate on a small cushion, so that it may be conveniently turned with the left hand, while the incisions are cut with the graving tool by the right. These lines are re-entered, crossed in various directions, or cut in the spaces between the diagonal crossings, until the desired effect is produced. Landscapes and architecture are generally executed with the needle and aquafortis: portraits and historical subjects are chiefly cut with the graver or burin, without the use of aquafortis. Where a series of parallel lines are wanted, as in backgrounds, &c. an ingenious machine, called a ruler, is employed, the accuracy of whose operation is exceedingly perfect. This is made to act on etching-ground by a point or knife connected with the apparatus, and bit in with aquafortis in the ordinary way. soft ground is used to imitate chalk or pencil-drawings. Mezzotinto is in a great measure a reversal of those styles already described, being the reducing of a darkened surface of copper to one that is light. The operation is generally commenced by grounding or puncturing the plate with a circular-faced tool, called a cradle, on the edge of which are a number of points; this instrument, by being rocked regularly over the surface of the copper in every direction, covers it so completely with marks, that, if it were printed from, the impression would be perfectly black. On this dark ground the subject is traced, directing where the various gradations of light and half-tint are to be scraped and burnished out, until the proper effect is produced. This style of engraving is used chiefly for portraits and historical subjects. It has a pleasing soft appearance, but it is understood that the copper soon fails in producing strong impressions, and it is therefore not well adapted for subjects of which great numbers are required. Aquatinto engraving is an exceedingly complicated style of producing pictorial effect; but being executed at a lower price than that of the kinds previously mentioned, it is commonly resorted to for embellishing books of travels, or other works requiring illustrations of a simple nature. In appearance it resembles tinting with Indian ink, and the prints are susceptible of being finished with water-colours. In commencing the process of aquatinto engraving, the plate must be cleaned As etching has become somewhat fashionable, and is with an oil-rubber, which is a strip of woollen cloth now pretty freely cultivated by amateurs, either as an rolled up hard, to about two inches in diameter; this, amusement, or with a view to illustrate discoveries in with a little impalpable crocus and sweet-oil, will give natural science, it may be well to mention that the art to the copperplate, when perfectly cleaned from the can be learned in a few lessons. Those who reside in oil, a proper surface to receive the ground, which is large towns, will most readily acquire it under the made with pulverised sifted rosin and spirits of wine, direction of some copperplate-engraver; those who have incorporated by gentle heat, till it appears like a varno such opportunity, may teach themselves by attend- nish. This composition is poured over the plate while ing to the directions given in Mr Alken's Art and placed in a slanting position, so as to permit the superPractice of Etching,' published by the Messrs Fuller, fluous liquid to run off. The operation must be so Rathbone Place, London, who also supply the entire managed as to preserve an equal surface. As soon as apparatus. The apparatus is by no means costly, and the granulation, or drying of the grain, appears, the consists of a few copper-plates, etching-needles, a hand-plate must be placed horizontally, when the spirit will rest, a ball of etching-ground, a dabber, oil-rubber, a evaporate, and the particles of rosin will adhere to little rottenstone, a smoking-taper, bordering-wax, some the copper. When dry, the surface appears evenly varnish for stopping out false lines, tracing-paper, and covered, as with a diminutive honeycomb, and pera phial of aquafortis. The great advantage of etching fectly smooth. On this the subject is traced, and the to the amateur consists in the opportunity it affords highest lights painted out with a sable pencil in a mixhim of multiplying impressions of his work. A sketch ture of turpentine-varnish and lampblack, so as to in oil or in water-colours remains single, and a copy prevent the aquafortis acting on those parts. The can only be obtained by repeating the process; whereas inargin is also covered, and on it a wall of wax is fixed, a sketch once etched can yield hundreds of impres- with a spout at one corner. The aquafortis is regusions, all precisely the same in every line and feature. lated in its strength by the temperature of the weather Those who can draw in reverse proceed at once to de- and the hardness of the copper. Being poured on the lineate on the etching-ground; but in general it is plate, it remains until the first gradation of tint is safer to draw on paper, and transfer. Etching with a bitten -the aquafortis having acted on the copper dry point, as it is called, is performed entirely with the between the particles of rosin which adhered to the point without any ground, the burr raised by the plate. The aquafortis is then taken off, the plate dried, graver being taken off by the scraper-a steel instru- and this first degree of tint stopped out or covered over ment with three sharp edges. Engraving or etching in | with the blackened varnish. When hard, the aqua fortis is again poured on, to bite the second degree of tint; and so on until all the tints have in succession been bitten in. The copper must then be cleaned, and a proof taken and compared with the original. A similar or rebiting grain must then be laid on the plate as before; when cold, a composition of treacle and lampblack, well mixed, must be used to paint the projections of foliage on lights, or other touches which the masses of tint may require. When these are dry, the whole of the plate must be washed over with a thin coat of varnish reduced with turpentine, which will adhere to the untouched parts of the work. The wall of wax must then be replaced, and clean water poured on; in a short time the water will mix with the treacle touches, and loosen them. When all appear to be removed, the water is taken off, and aquafortis poured on, and allowed to remain until a sufficient degree of power is given to the touches, and the subject completed. This mode of engraving was invented by a Frenchman of the name of St Non, about the year 1662. He communicated the process to Jean Baptiste le Prince, who died in 1781, from whom it was acquired by Paul Sandby, who introduced it, through the medium of Mr Jukes, into this country. It has been practised in England with much greater success than anywhere else, but latterly has been superseded in many instances by lithography. Plate-Printing.-Copperplates, engraved in any of the above styles, are ready for press as soon as they are finished by the engraver. The method of printing from them is very simple. Their engraved surface is daubed over with a thick oleaginous ink, so that the lines are effectually filled. As this dirties the whole face of the plate, it is necessary to clean it, which is done by the workman wiping it first with a piece of canvas, and then with the palms of his hands, rubbed on fine whiting. It may be calculated that a hundred times more ink is thus removed than actually remains in the indentations; however, such is necessary. The plate being thoroughly cleaned, it is laid on a press (see fig.), with a piece of damped paper over it, and being wound beneath a roller covered with blanket stuff, it is forced to yield an impression on the paper. The plate requires to be kept at a moderate warmth during the operation. The frequent rubbing of the plate with the hand to clean it, as may be supposed, tends greatly to wear it down; and such is the wear chiefly from this cause, that few copperplates will yield more than a few thousands of impressions in good order. The earliest, called proofs, are always the best, and most highly prized. In consequence of this defect in copper, the practice of engraving steel plates, for all subjects requiring long numbers, has now become very common. This process was introduced by the late Mr Perkins of London, who originally softened the plates, engraved them, and then rehardened them-a practice now abandoned, as ordinary steel plates can be worked upon by the burin, dry-point, scraper, and burnisher with perfect facility. Etching on steel plates is executed much in the same way as in the process on copper. The plate is bedded on common glaziers' putty, and a ground of Brunswick black is laid on in the usual way, through which the needle scratches. The biting menstruum is then poured on, and managed in the manner already detailed. An engraving on a steel plate may be transferred in relief to a softened steel cylinder by pressure; and this cylinder, after being hardened, may again transfer the design by rolling it upon a fresh steel plate; and thus the design may be multiplied at pleasure. SEAL AND GEM ENGRAVING. This is a branch of the profession altogether distinct from that of engraving on metallic plates. While the hardest metals are susceptible of being cut by a tool wielded by the hand of the artist, the different kinds of stone required to be operated upon by the seal-engraver are so extremely hard, that a much more powerful instrument than the hand has to be resorted to. The cutting-tool is fixed into a turning-machine or lathe, and is made to operate while in a rapid rotatory motion. The lathe is of a light and miniature construetion, erected on an elevated bench or table in front of the artist, and is moved by a foot-board beneath. The engraver of metal-plates sits while at his work, but the seal-engraver in general stands, in order to have greater command over his operations. He likewise requires to be exceedingly steady in the hand, for the slightest error would perhaps be irremediable; therefore, with both his elbows resting on cushions on the bench, and the palm of his left hand leaning on the top of an erect roundish-shaped bolt or pillar, his fingers of both hands are busy in pressing the stone to the edge of the whirling-tool, or guiding it so that it may receive the appropriate indentations. One tool, however, cannot execute all parts of the device. The cutter possesses from one to two hundred tools, usually of soft iron or copper, varying from a large to a small size. It is also necessary to explain that the cutting part of each tool is shaped so as to present to the stone a sharp thin edge like the rim of a wheel. (By sticking a small wafer on the point of a pin, and conceiving the edge of the wafer, when turning round, to be the cutting part, a good idea may be obtained of this curious instrument.) As the tool projects horizontally, the artist, by holding the stone beneath it, with its surface to be cut uppermost, is thus enabled to watch the progress of his operation from beginning to end. Sharp as the cutting tools of the seal-engraver are, they would entirely fail in perforating the gems to which they are applied by the lathe, unless they were given an additional sharpness by means of a foreign material occasionally applied to them while in rapid motion. This material is usually diamond dust, or the powder of the ruby and other hard stones. The diamond is so expensive an article, that the particles used by the seal-engraver are those which have been rejected as waste by the lapidary. These being placed in a hollow steel tube, having a tight-fitting raminer of the same material, a few smart blows on the upper extremity of the rammer reduce the particles to powder. A small portion of this dust is then mixed with a little olive oil, and being held to the tool in a state of motion, it is attached to or forced into the metal. If a powerful magnifying-glass were taken to examine the tool after its absorption of the diamond dust, its edge would be observed to resemble a rasp or saw, the particles being partly imbedded and fixed in the steel; hence, properly speaking, it is not the tool, but the diamond dust upon it, which cuts the surface of the stone. To cut an elaborate device, such as a bust or a cost of arms, upon the surface of a cornelian or other gem, a vast deal of care is necessary on the part of the artist. The precise depth of every turn and indenta tion is matter of serious study, and a momentary heedlessness might have the effect of ruining the work of several days. The operator, however, exercises caution in his ingenious labour. The stone being dimmed by friction, is drawn upon with a brass point, to show the subject, which is of course reversed: the artist first traces the outlines of his figures, next opens them with The the bolder tools, and gradually proceeds to the details | rubbed over with wax, the temperature of the glass with finer and finer instruments, frequently stopping being high enough to cause the wax to melt, and be to take impressions on wax, to see the effect which has distributed uniformly over the entire surface. been produced, before he gives the finishing stroke to glass is then set aside to cool; and when the wax has his workmanship; lastly, the surface is repolished, and become quite solid, the design may be traced with a the seal completed. pointed, but not very fine instrument, such as a bodkin. A carpenter's bradawl is a convenient tool for this operation, since, from being flattened at the end in one direction, it may be made to trace lines of different degrees of fineness, according to the position in which is held. Care must be taken to cut through the entire thickness of the wax, so as to lay the glass quite bare through the whole length of the line. It will thus be seen that gem-engraving requires not only great ability and skill, but a degree of patience and perseverance beyond what is required in most other professions. To cut a metallic seal or die is comparatively an easy task-the instruments as well as material being thoroughly under the control of the artist; but to engrave on the hardest gems, whose nature cannot be altered, and which, if destroyed, cannot be replaced-to carve the most minute and delicate figures, and to produce them in such a manner as to yield a distinct and smooth impression-is altogether an art of the highest order. ENGRAVING AND ETCHING ON GLASS. The name of cut glass is given in commerce to glass which is ground and polished in figures with smooth surfaces, appearing as if cut by incisions of a sharp instrument. This operation is chiefly confined to flintglass (see No. 21), which, being more tough, soft, and brilliant than the other kinds, is more easily worked, and produces specimens of greater lustre. An establishment for cutting glass contains a great number of wheels or disks, seldom exceeding a foot in diameter, which are made to revolve with great rapidity by steam or other moving power. Against the circumferences or edges of these revolving wheels the glass to be ground or figured is held by the hand of the workman. The thickness of the cutting disks, and the forms of their edge, are varied considerably; some being broad, others narrow; some convex, others concave; some flat-edged, others wedge-shaped; and so on, according to the shape of the vessel and the figures to be produced. Even forty or fifty disks with different-shaped edges may be found in the same workshop. Materials of very different degrees of hardness, from cork to wrought-iron, are employed in the formation of these disks. Those made of wrought-iron, which are very thin, are used to cut grooves in glass, by the aid of sand and water, which are caused to drop on the circumference of the disk from hoppers placed above. Cast-iron disks are also sometimes used in the roughest part of the operation; but the coarse work is usually done by a disk of fine sandstone wetted with water. When ground down to the proper shape, the glass is polished by exposure to softer disks, the action of which is generally assisted by various powders applied in a moist state to the circumference. Thus a copper disk is used with emery and oil; a disk of block-tin with peroxide of tin or tutty; a disk of willow-wood with fine pumicestone, colcothar, or putty; and a cork disk having an edge of hat felt with putty or colcothar.' By such simple instruments is all that variety of design-flower, fruit, foliage, arabesque tracery, initials, armorial bearings, &c.-produced which now adorns so abundantly the most familiar articles of domestic utility. The art of etching on glass is altogether different, being akin to etching on plates of copper and steel. The art,' says Parnell in his 'Applied Chemistry,' may be practised on all kinds of glass; but the most proper description is good crown-glass. The facts on which this art is founded are, that the vapour of hydrofluoric acid (see No. 19) acts energetically on glass, corroding it as aquafortis does a sheet of copper, and that certain parts of the glass may be easily protected by a resial varnish, on which the acid exerts no action except at a high temperature. The varnish usually employed by artists for this purpose is either common turpentine varnish mixed with a little white-lead, or a strong aqueous solution of isinglas. In performing the process on a small scale, purified bees'-wax will be found to form a convenient varnish. The piece of glass to be etched is first of all warmed in a convenient manner, and one of its surfaces is then The next part of the process consists in the application of the hydrofluoric acid. The vessel employed for this purpose is a shallow basin, either of lead or of Wedgwood's ware (no glazed vessel should be enployed), large enough to include within its area every part of the design, when the prepared glass is placed upon its edge. The materials for generating hydrofluoric acid-consisting of one part of powdered fluor spar, and about two parts of highly concentrated oil of vitriol-are introduced into the basin, and well mixed; the glass plate is then laid on the edge of the basin, with the waxed side undermost, and a moderate heat is applied, to disengage the vapour of hydrofluoric acid. A spirit-lamp will be found a convenient source of heat, from the facility it affords of increasing or decreasing the temperature at pleasure. Care must be taken to prevent the heat becoming so powerful as to melt the wax-ground. After being exposed to the acid fumes for a few minutes, the glass plate may be removed and cleaned. The lines where the wax had been removed are found to be covered with a white powder, which consists of silico-fluorides of the metallic bases of the glass. The greater part of the wax may be removed by scraping with a common table-knife, and the remainder by warming the glass before the fire, and wiping it with tow and a little oil of turpentine. The design will then be found to be perfectly etched upon the surface of the glass, the depth of the lines being proportional to the time the glass was exposed to the acid vapour. In conducting the operation, care should be taken not to allow the hands to become exposed to the acid fumes, as the vitality of the parts would be instantly destroyed by the action of the acid.' According to the authority now quoted, a dilute aqueous solution of hydrofluoric acid may be substituted for the vapour in the above process with a similar result. Glass plates engraved upon in this manner are not adapted for printing, or yielding impressions upon paper, on account of their brittleness; but even this has been partially obviated by a German invention, wherein the glass, of considerable thickness, is cemented to blocks of wood-the plates so mounted enduring sufficient pressure to produce a fair impression without fracture. GLYPHOGRAPHY. An important addition to our means of producing pictures or impressions consists in the glyphographic process of Mr Palmer. The peculiar advantages of this invention-so named from its combining two distinct operations of drawing and engraving—are thus detailed by the patentee:- The term glyphography is derived from two Greek words (glypho, I engrave, and graphein, to draw), and signifies that art by which an engraving is produced by the simple mode of drawing; or, in other words, drawing and engraving, which have hitherto been two distinct operations, are here combined in one. Hence its merits, and importance to every artist, seeing that by its aid he becomes the engraver of his own work, as much as he would by the practice of etching; but with this vast difference, that here his effect is as immediately conspicuous as though he were using a black-lead pencil on paper; whilst, on the contrary, effect is obtained in etching in the same manner as in line-engraving-namely, by depth; and that depth the etcher produces by the action of acid on the copper, called biting; nor has he any means of ascertaining the real effect thus produced but by taking a proof on paper, and of course he must repeat this as often as he makes any alteration in his plate. Another material advantage which glyphography possesses over etching and wood-engraving is, that in the former the artist draws his subject as he intends it to appear, without reversing it, as is requisite in both the latter, and which is extremely difficult and perplexing, at least to beginners. And last, though by no means least of its peculiar merits, and that which makes it of the highest importance to every true lover of the fine arts, is the freedom afforded to the artist, and consequent scope for the exercise of his talent, and multiplication of fac-similes of his own work. Every connoisseur in the arts knows what sort of comparison to make between etchings and any other kind of prints, although they may be the productions of the same hand; and why? Simply on account of the stiff formality and studied regularity of the latter, which, though perhaps pleasing to the eye, are by no means natural; consequently the same facilities are here afforded as in etching, without that tediousness associated therewith, and the other disadvantages already enumerated. So tied and fettered is the wood-draughtsman, that he is obliged to leave the tints entirely to the engraver's taste and skill, contenting himself with staining with India ink, &c. that part of the block to the desired colour or tone; nor is his outline secure, unless in the hands of a clever cutter, and even then its freedom and beauty are sometimes entirely spoiled from a variety of causes; but in glyphography, on the contrary, any sort of work, whether sketchy or finished, free or formal, is introduced with equal ease (according to the skill and experience of the artist); and, moreover, what may seem strange to those unacquainted with the nature of the after-process, the more elaborate and complicated the drawing, the less time and trouble is required in its conversion into a surface-printing block, as hereafter described. If anything further needs observation here, regarding the many advantages that this new art possesses, it is, first, the durability of the blocks, seeing that, with care, the number of proofs taken therefrom may be multiplied almost ad infinitum, upwards of 70,000 having been taken from one without altering in the least degree its sharpness; and next, in a commercial point of view, is its extreme cheapness, which of course is worthy of consideration.' Such are the proffered advantages of the invention; let us now glance at the process so far as divulged by Mr Palmer: A piece of ordinary copper-plate, such as is used for engraving, is stained black on one side, over which is spread a very thin layer of a white opaque composition, resembling white wax both in its nature and appearance: this done, the plate is ready for use. In order to draw properly on these plates, various sorts of points are used, which remove, wherever they are passed, a portion of the white composition, whereby the blackened surface of the plate is exposed, forming a striking contrast with the surrounding white ground, so that the artist sees his effect at once. The drawing being thus completed, is put into the hands of one who inspects it very carefully and minutely, to see that no part of the work has been damaged, or filled in with dirt or dust; from thence it passes into a third person's hands, by whom it is brought in contact with a substance having a chemical attraction or affinity for the remaining portions of the composition thereon, whereby they are heightened ad libitum. Thus by a careful manipulation the lights of the drawing become thickened all over the plate equally, and the main difficulty is at once overcome; a little more, however, remains to be done. The depth of these non-printing parts of the block must be in some degree proportionate to their width; consequently the larger breadths of lights require to be thickened on the plate to a much greater extent, in order to produce this depth. This part of the process, however, is purely mechanical, and easily accomplished. It is indispensably necessary that the printing surfaces of a block prepared for the press should project in such relief from the block itself as shall prevent the probability of the inking-roller touching the interstices of the same whilst passing over them; this is accomplished in wood-engraving by cutting out these intervening parts, which form the lights of the print, to a sufficient depth; but in glyphography the depth of these parts is formed by the remaining portions of the white composition on the plate, analogous to the thickness or height of which must be the depth on the block, seeing that the latter is in fact (to simplify the matter) a cast or reverse of the former. But if this composition was spread on the plate as thickly as required for this purpose, it would be impossible for the artist to put either close, fine, or free work thereon; consequently the thinnest possible coating is put on the plate previously to the drawing being made, and the required thickness obtained ultimately as described. The plate thus prepared is again carefully inspected through a powerful lens, and closely scrutinised, to see that it is ready for the next stage of the process, which is, to place it in a trough, and submit it to the action of a galvanic battery, by means of which copper is deposited into the indentations thereof, and continuing to fill them up, it gradually spreads itself all over the surface of the composition, until a sufficiently thick plate of copper is obtained, which, on being separated, will be found to be a perfect cast of the drawing which formed the clichee. Lastly, the metallic plate thus produced is soldered to another piece of metal to strengthen it, and then mounted on a piece of wood, to bring it to the height of the printer's type. This completes the process, and the glyphographic block is now ready for the press. It should, however, have been stated previously, that if any parts of the block require to be lowered, it is done with the greatest facility in the process of mounting.' What progress Mr Palmer's process may be making as a substitute for wood-engraving we have no means of knowing. Very delicate and beautiful specimens of glyphography have appeared in the Art Journals; but in volumes which have been illustrated throughout by the process, and printed in the usual manner-such as Dr Lindley's botanical works-while the drawings have undoubtedly considerable breadth and freedom, the impressions are vastly inferior in delicacy and clearness to those from ordinary woodcuts. Lithography (Gr. lithos, a stone, and graphein, to draw) is the art of printing from a peculiar kind of stone, and generally in a style which resembles the more ordinary kinds of engravings. It was invented at Munich in Bavaria, between the years 1795 and 1798, by Aloys Sennefelder, a person of literary ability, who, being too poor to pay for the printing of books in the usual manner, endeavoured to fall on a method of executing his productions from the surface of various metals. He found'-we quote the Encyclopædia Americana'-' in the course of his experiments that a composition of soap, wax, and lampblack formed a good material for writing on his plates; that, when dry, it became firm and solid, and that it resisted aquafortis. Wanting facility in writing backwards on the plates, he got some pieces of Kilheim-stone, as cheap materials on which he could practise after polishing their surfaces. One day, being desired by his mother to take an account of some linen about to be sent to be washed, and having no paper at hand, he wrote the account on a polished stone with his composition ink, intending to copy it at his leisure. When he was afterwards about to efface this writing, it occurred to him that he might obtain impressions from it; and having eaten away the stone with acid for about the hundredth part of an inch, he found that he could charge the lines with printing-ink, and take successive |