A History of Inventions, Discoveries, and Origins, Volume II (of 2). Johann Beckmann

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СКАЧАТЬ before-mentioned year, an account of it, in which he asserts, more than once, that he was the first person who had made the discovery publicly known. In his opinion it was occasioned by the remark that salt water in summer was always cooler than fresh water. According to his directions, which are illustrated by a figure, the liquor must be put into a bottle or globular vessel with a long neck, that it may be held with more convenience; and this vessel must be immersed in another wide one filled with cold water. Saltpetre must then be thrown gradually into the water; and while it is dissolving, the bottle must be driven round with a quick motion on its axis, in one direction. Villafranca thinks that the quantity of saltpetre should be equal to a fourth or fifth part of the water; and he assures us, that when again crystallized, it may be employed several times for the same use, though this, before that period, had by many been denied. Whether other salts would not produce the like effect, the author did not think of trying; but he attempts to explain this of saltpetre from the principles of Aristotle; and he tells his noble patrons what rules they should observe for the preservation of their health, in regard to cooling liquors.

      Towards the end of the sixteenth century this method of cooling liquors was well known, though no mention is made of it by Scappi, in his book on cookery. Marcus Antonius Zimara, however, speaks of it in his Problems399. I do not know at what time this Appulian physician lived. In a list of the professors of Padua, his name is to be found under the year 1525, as Explicator philosophiæ ordinariæ; and because another is named under the year 1532, we have reason to conjecture that he died about that time. But in that case the physician Villafranca would probably have been acquainted with the Problemata of Zimara; and would not have said that no one had spoken of this use of saltpetre before him.

      Levinus Lemnius400 also mentions the art of cooling wine by this method so much, that the teeth can scarcely endure it. We are informed by Bayle that the earliest edition of his work, which has been often reprinted, was published at Antwerp, in the year 1559, in octavo. It contains only the first two books; but as the above account occurs in the second book, it must be found in this edition.

      Nicolaus Monardes, a Spanish physician, who died about the year 1578, mentions this use of saltpetre likewise. It was invented, as he says, by the galley-slaves; but he condemns it as prejudicial to health. From some expressions which he uses, I am inclined to think that he was not sufficiently acquainted with it; and that he imagined that the salt itself was put into the liquor. At a later period we find some account of it in various books of receipts; such as that written by Mizaldus in 1566, and which was printed for the first time the year following401.

      In the Mineralogy of Aldrovandi, first printed in 1648, this process is described after Villafranca; but where the editor, Bartholomæus Ambrosianus, speaks of common salt, he relates that it was usual in countries where fresh water was scarce to make deep pits in the earth; to throw rock-salt into them; and to place in them vessels filled with water, in order that it might be cooled. This remark proves that the latter salt was then employed for the same purpose; but it has led the editor into a very gross error. He thinks he can conclude from it, that the intention of potters, when they mix common salt with their clay, is not only to render the vessel more compact, but also to make it more cooling for liquors. But the former only is true. The addition of salt produces in clay, otherwise difficult to be fused, the faintest commencement of vitrification; a cohesion by which the vessel becomes so solid that it can contain fluids, even when unglazed; but for this very reason it would be most improper for cooling, which is promoted by the evaporation of the water that oozes through.

      The Jesuit Cabeus, who wrote a voluminous commentary on the Meteorologica of Aristotle, which were printed at Rome in 1646, assures us that with thirty-five pounds of saltpetre one can not only cool a hundred pounds of water, by quickly stirring it, but convert it also into solid ice; and for the truth of this assertion he refers to an experiment which he made. Bartholin says that for the above account he can give him full credit402; but the truth of it is denied by Duhamel, who suspects that this Jesuit took the shooting crystals of the salt to be ice403.

      Who first conceived the idea of mixing snow or ice with saltpetre and other salts, which increases the cold so much, that a vessel filled with water, placed in that mixture, is congealed into a solid mass of ice that may be used on the table, I cannot with certainty determine; but I shall mention the earliest account of it that I have been able to find. Latinus Tancredus, a physician and professor at Naples, whose book De Fame et Siti was published in 1607, speaks of this experiment; and assures us that the cold was so much strengthened by saltpetre, that a glass filled with water, when quickly moved in the above mixture, became solid ice404.

      In the year 1626, the well-known commentary on the works of Avicenna, by Sanct. Sanctorius, was published at Venice. The author in this work relates, that in the presence of many spectators, he had converted wine into ice, not by a mixture of snow and saltpetre, but of snow and common salt405. When the salt was equal to a third part of the snow, the cold was three times as strong as when snow was used alone.

      Lord Bacon, who died in 1626, says that a new method had been found out of bringing snow and ice to such a degree of cold, by means of saltpetre, as to make water freeze. This, he tells us, can be done also with common salt; by which it is probable he meant unpurified rock-salt; and, he adds, that in warm countries, where snow was not to be found, people made ice with saltpetre alone; but that he himself had never tried the experiment406. Boyle, who died in 1691, made experiments with various kinds of salts; and he describes how, by means of salt, a piece of ice may be frozen to another solid body407. Descartes says that in his time this was a well-known phænomenon, but highly worthy of attention408.

      Since that period the art of making ice has been spoken of in the writings of all philosophers where they treated on heat and cold, and with many other experiments has been introduced into various books of receipts. It was then employed merely for amusement409; and no one suspected that it would ever form an important item of luxury. In the like manner Fugger’s first bills of exchange were said to be useful only for gambling, and gunpowder was called a trifling discovery.

      In the beginning of the seventeenth century, drinking-cups made of ice and iced fruit were first brought to the table; but towards the end of that century it appears that the French began to congeal in this manner all kinds of well-tasted juices, which were served up as refreshments at the tables of the great and wealthy410. This was a grand invention for the art of cookery; which became common among the German cooks, both male and female, about the middle of the last century; and since that time our confectioners sell single glasses of iced articles at balls and in the theatres.

      I am acquainted with no older information respecting this invention than what is contained in Barclay’s Argenis, which is, indeed, a romance; but the author’s account makes the possibility of its being used so clear, that we may certainly conclude it was then employed; especially as he mentions it several times. Arsidas finds in the middle of summer, at the table of Juba, fresh apples, one-half of which was encrusted with transparent ice. A basin, made also of ice and filled with wine, was handed to him; and he was informed that to prepare all these things in summer was a new art. Snow was preserved throughout the whole year in pits lined with straw. Two cups made of copper were placed the one within the other, so as to leave a small space between them, which was filled with water; the cups were then put into a pail, amidst a mixture of snow and unpurified salt coarsely pounded, and the water in three hours was converted into a cup of solid ice, as well-formed as if it had come from the hands of a pewterer. In the like manner apples just pulled from the tree СКАЧАТЬ