WINES (see that article, Encycl. and Vegetable Substances, Suppl.) are so often adulterated with minerals prejudicial to the health, that various methods have been devised for detecting the adulteration. The property which liver of sulphur (alkaline sulphures) and hepatic air (sulphurated hydrogen) possess of precipitating lead in a black form, has been long ago made public; and this property has been employed to determine the quality of wines by means of the liquor probatorius Wirttembergensis, or Wirttemberg proving liquor. But in trying wines supposed to have been adulterated, this proof does more hurt than service, because it precipitates iron of the same colour as the pernicious lead. Many wine-merchants, therefore, of the greatest respectability, rendered by these means suspected, have been ruined.
The following is recommended by M. Hanemann as a better test of sound wines than the proving liquor of Wirttemberg. Mix equal parts of oyster shells and crude sulphur in a fine powder, and put the mixture into a crucible. Heat it in a wind furnace, and increase the fire suddenly, so as to bring the crucible to a white heat, for the space of 15 minutes. Pulverise the mass when it is cool, and preserve it in a bottle closely stopped.
To prepare the liquor, put 120 grains of this powder, and 120 grains of cream of tartar (acidulous tartaric of potash), into a strong bottle; fill the bottle with common water, which boil for an hour, and then let it cool; close the bottle immediately, and shake it for some time: after it has remained at rest to settle, decant the pure liquor, and pour it into small phials capable of holding about an ounce each, first putting into each of them 20 drops of muriatic acid. They must be stopped very closely with a piece of wax, in which there is a small mixture of turpentine.
One part of this liquor, mixed with three parts of suspected wine, will discover, by a very sensible black precipitate, the least traces of lead, copper, &c. but will produce no effect upon iron, if it contains any of that metal. When the precipitate has fallen down, it may still be discovered whether the wine contains iron, by saturating the decanted liquor with a little salt of tartar (tartareous acidulum of potash), by which the liquor will immediately become black. Pure wines re-
main clear and bright after this liquor has been added Wood-cuts.
WOOD-CUTS are engravings on wood, commonly on box, which, in many cases, are used with advantage instead of copper-plates. The art of cutting or engraving on wood is undoubtedly of high antiquity: for Chinese printing is a specimen of it. (See CHINA, n° 127. Encycl.) Even in Europe, if credit be due to Papillon, this art was practised at a period considerably remote; for he mentions eight engravings on wood, entitled, "A representation of the warlike actions of the great and magnanimous Macedonian king, the bold and valiant Alexander; dedicated, presented, and humbly offered, to the most holy father, Pope Honorius IV. by us Alexander Alberic Cunio Chevalier, and Isabella Cunio, &c." This anecdote, if true, carries the art of cutting in wood back to 1284 or 1285; for Honorius occupied the papal throne only during these two years. Even this is not the remotest period to which some have carried the art in Europe; for the use of seals or sig-nas being of very high antiquity, they imagine that the invention of wood-cuts must be coeval with them. The supposition is certainly plausible, but it is not supported by proof. The earliest impression of a wooden-cut, of which we have any certain account, is that of St Christopher carrying an infant Jesus through the sea, in which a hermit is seen holding up a lantern to shew him the way; and a peasant, with a sack on his back, climbing a hill, is exhibited in the background. The date of this impression is 1423.
In the year 1430 was printed at Haarlem, "The history of St John the evangelist and his revelation, represented in 48 figures in wood, by Lowrent Janfon Colter;" and, in 1448, Jörg Schappf of Augsburg cut in wood the history of the Apocalypse, and what was called The poor man's bible. (See ENGRAVING, Encycl. page 668.)
A folio chronicle, published 1493 by Schedal, was adorned with a vast number of wood-cuts by William Plydenwurff and Michael Wolgemut, whose engravings were greatly superior to any thing of the kind which had appeared before them. Wolgemut was the preceptor of Albert Durer, whose admirable performances in this department of art are justly held in the highest esteem even at the present day.
About this period it became the practice of almost all the German engravers on copper to engrave likewise on wood; and many of their wood-cuts surpass in beauty the impressions of their copper-plates. Such are the wood-cuts of Albert Aldorfer, Hissel Pez, Virgil Soles, Lucas van Crannach, and Lucas van Lyden, the friend and imitator of Albert Durer, with several others.
It appears that the Germans carried this art to a great degree of perfection. Hans or John Holbein, who flourished in 1500, engraved the Dance of Death, in a series of wooden-cuts, which, for the freedom and delicacy of execution, has hardly been equalled, and never surpassed.
Italy, France, and Holland, have produced many capital artists of this kind. Joan. Tormesum printed a bible at Lyden, in 1554 (a copy of which we have seen), with wooden-cuts of excellent workmanship. Christopher Jegher of Antwerp, from his eminence in the art, was employed by Rubens to work under his inspection,
Wood-cuts. inspection, and he executed several pieces which are held in much estimation; the character of these is boldness and spirit.
The next attempt at improvement in this art was by Hugo da Carpi, to whom is attributed the invention of the chiaro scuro. Carpi was an Italian, and of the 16th century; but the Germans claim the invention also, and produce in evidence several engravings by Mair, a disciple of Martin Schoen, of date 1499. His mode of performing this was very simple. He first engraved the subject upon copper, and finished it as much as the artists of his time usually did. He then prepared a block of wood, upon which he cut out the extreme lights, and then impressed it upon the print; by which means a faint tint was added to all the rest of the piece, excepting only in those parts where the lights were meant to predominate, which appear on the specimens extant to be whitened with white paint. The drawings for this species of engraving were made on tinted paper with a pen, and the lights were drawn upon the paper with white paint.
There is, however, a material difference between the chiaro scuro of the old German masters and those of the Italians. Mair and Cranach engraved the outlines and deep shadows upon copper. The impression taken in this state was tinted over by means of a single block of wood, with those parts hollowed out which were designed to be left white upon the print. On the contrary, the mode of engraving by Hugo da Carpi was, to cut the outline on one block of wood, the dark shadows upon a second, and the light shadows, or half tint, upon a third. The first being impressed upon the paper, the outlines only appeared; this block being taken away, the second was put in its place, and being also impressed on the paper, the dark shadows were added to the outlines; and the third block being put in the same place upon the removal of the second, and also impressed upon the paper, made the dim tints, when the print was completed. In some instances, the number of blocks were increased, but the operation was still the same, the print receiving an impression from every block.
In 1698, John Baptist Michel Papillon practised engraving on wood with much success, particularly in ornamental foliage and flowers, shells, &c. In the opinion, however, of some of the most eminent artists, his performances are stiff and cramped. From that period the art of engraving on wood gradually degenerated, and may be said to have been wholly lost, when it was lately re-invented by Mr Bewick of Newcastle.
This eminent artist was apprentice to Mr Bielby, an engraver on metal of the very lowest order, who was seldom employed in any thing more difficult than the cutting of the face of a clock. Application having been made to this man for a wood-cut or two of the most trifling description, the job was given to Thomas Bewick; by whom it was executed in such a manner,