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

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СКАЧАТЬ nor by any other author. The foolish taste for alchemy, which prevailed then at the duke’s court, makes it not altogether improbable that one was issued103; and if that was really the case, it was occasioned not so much by any dread of this metal being misused, as Pott thinks, but by the high hopes which were entertained of its utility in making gold. The first accurate and certain account of the method of procuring zinc at Goslar, is, as far as I know, given by Lœhneyss, in 1617, though he considers it to be the same as bismuth104. Joh. Schrœder of Westphalia, who died in 1664, calls it marcasita pallida.

      The first person who purposely procured this metal from calamine, by the addition of some inflammable substance, was undoubtedly Henkel, who gave an account of his success in the year 1741, though he concealed the whole process105. After him, Dr. Isaac Lawson, a Scotsman, seems to have made experiments which proved the possibility of obtaining zinc in this manner on a large scale; and in 1737 Henkel heard that it was then manufactured in England with great advantage. Of this Lawson I know nothing more than what is related by Dr. Watson106. Anthony von Swab, member of the Swedish council of mines, procured this metal afterwards from calamine by distillation, in 1742; as did Marggraf in 1746, who appears however not to have been acquainted with the Swedish experiment. In the year 1743, one Champion established zinc works at Bristol, which were continued by his successor James Emerson, who established works of the like kind at Henham, in the neighbourhood. The manner in which the metal was procured, has been described by Dr. Watson in his Chemical Essays.

      The greater part of this metal, used in Europe, was undoubtedly brought from the East Indies. The Commercial Company in the Netherlands, between the years 1775 and 1779, caused to be sold, on their account, above 943,081 pounds of it107. In the year 1780, the chamber of Rotterdam alone sold 28,000 pounds; and I find, by printed catalogues, that the other chambers, at that period, had not any of it in their possession. If the account given by Raynal be true, the Dutch East India Company purchased annually, at Palimbang, a million and a half of pounds108. In 1781, the Danish Company at Copenhagen purchased 153,953 pounds of tutenage, which had been carried thither in two vessels, at the rate of from four and one-eighth to four and a quarter schillings Lubec per pound. It is probable that the English and Swedes import this article also. It would be of some consequence if one could learn in what part of India, when, and in what manner this metal was first procured, and in what year it was first carried thence to Europe. According to the scanty information which we have on the subject, it comes from China, Bengal, Malacca109, and the Malabar coast, from which copper and tin are also imported. In the oldest bills of lading of ships belonging to the Netherlands I find no mention of zinc; but it is possible that it may be comprehended under the name of Indian tin; for so it was at first called. Savot, who died about the year 1640, relates, on the authority of a contemporary writer110, that some years before the Dutch had taken from the Portuguese a ship laden with this metal, which was sold under the name of speautre. It is probable therefore that it was brought to Europe so early as the beginning of the seventeenth century. Indian tin is mentioned by Boyle.

      It is probable that this metal was discovered in India before anything of the European zinc had been known in that country; but we are still less acquainted with the cause of the discovery than with the method of procuring the metal. We are told that an Englishman, who, in the above century, went to India, in order to discover the process used there, returned with an account that it was obtained by distillation ver descensum.

      Respecting the origin of the different names of this metal, I can offer very little. Conterfey signified formerly every kind of metal made in imitation of gold111. Frisch says it was called zink, from which was formed first zinetum, and afterwards zincum, because the furnace-calamine assumes the figure of (zinken or zacken) nails or spikes; but it is to be remarked that these names do not occur before the discovery of this metal, though ofenbruch was known long before. Fulda speaks of the Anglo-Saxon sin, zink, which he translates obryzum. Spiauter, speauter, and spialter, from which Boyle made speltrum, and also tutaneg or tuttanego, came to us from India with the commodity. Under the last-mentioned name is sometimes comprehended a mixture of tin and bismuth. Calaem is also an Indian appellation given to this metal, and has a considerable likeness to calamine; but I am of opinion with Salmasius that the latter is not derived from the former, as lapis calaminaris occurs in the thirteenth century, and calaem was first brought to us by the Portuguese from India.

      [Most of the zinc works in this country are situated in the neighbourhood of Birmingham and Bristol; a few furnaces also exist in the neighbourhood of Sheffield, among the coal-pits surrounding that town; there is also one at Maestag in Glamorganshire. The ores worked at Bristol and Birmingham are principally obtained from the Mendip-hills and Flintshire; those at Sheffield from Alston Moor. The greater part however of the zinc used in this country is imported in ingots and plates from Silesia, by way of Hamburg, Antwerp, Dantzic, &c. We receive annually from 100,000 to 170,000 cwts. from Germany; of this quantity, about 80,000 cwt. are entered for home consumption, and the rest is exported for India.

      From its moderate price and the ease with which it can be worked, zinc is now extensively used for making water-cisterns, baths, pipes, covering of roofs, and a great many architectural purposes. It has also of late been employed in the curious art of transferring printing, known under the name of Zincography, but owing to the ease with which this metal becomes coated with a film of oxide or carbonate, by exposure to the air, the plates cannot be preserved for any great length of time.]

      CARP

      So obscure is the ichthyology of the ancients, or so little care has been taken to explain it, that the question whether our carp were known to Aristotle, Pliny, and their contemporaries, cannot with any great degree of probability be determined. Besides, that subject is attended with much greater difficulties than the natural history of quadrupeds. Among four-footed animals there is a greater variety in their bodily conformation, which at any rate strikes the eye more, and can be more easily described than that of fishes, which in general are so like in shape, that an experienced systematic naturalist finds it sometimes difficult to determine the characters of the genera and species. It is not surprising therefore that the simple descriptions of the ancients, or rather the short accounts which they give us of fish, do not afford information sufficient to enable us to distinguish with accuracy the different kinds. Quadrupeds may terrify us by their ferocity, or endeavour to avoid us by shyness and craft; but it is still possible to observe their sexes, their age, and their habits, and to remark many things that are common to one or only a few species. Fishes, on the other hand, live in an element in which we cannot approach them, and which for the most part conceals them from our observation. The chase, since the earliest periods, and in modern times more than formerly, has been the employment of idle persons, who bestow upon it greater attention the fewer those objects are which can attract their curiosity or employ their minds: but fishing has almost always been the laborious occupation of poor people, who have no time to make observations, as they are obliged to follow it in order to find a subsistence; and mankind in general seldom see fish except on their tables or in collections of natural history. On this account those properties of fish by which their species could be determined, were less known. The descriptions of four-footed animals which have been handed down to us from the time of the Greek and Roman writers, give us, at any rate, some information; but from those of fishes, which are more uncommon, we can scarcely derive any; unless one were as acute or easy of belief as many collectors of petrefactions, who imagine that they can distinguish each species of fish in the impressions which they see in stones. More however might be done towards elucidating the ichthyology of the ancients than has hitherto been attempted. It would be necessary only to make a beginning СКАЧАТЬ