A History of Inventions, Discoveries, and Origins (Vol. 1&2). Johann Beckmann

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СКАЧАТЬ its attracting of small bodies in the same light as that power which our hyacinth has in common with all stones of the glassy species, I cannot see anything to controvert this opinion, and to induce us to believe the lyncurium and the tourmaline to be the same. The grounds which Watson produces for this supposition, are more in favour of the hyacinth than the tourmaline213. Had Theophrastus been acquainted with the latter, he would certainly have remarked that it did not acquire its attractive power till it was heated. At present, at least, no tourmaline is known to attract until it is heated; though it would not appear very wonderful if a stone like the magnet should retain its virtue for a long time.

The duke of Noya Caraffa believes the theamedes of the ancients to have been the tourmaline214. Of that stone we are told, by Pliny, only that it possessed a power contrary to the power of the magnet; that is, that it did not attract but repel iron. But this only proves, that it had then been remarked that the magnet repelled the negative pole of a piece of magnetic iron. This account has been thus explained by Boot215. To induce us to consider the theamedes as the tourmaline, Pliny ought to have said that it attracted iron and then repelled it.

With much greater probability may we consider as the tourmaline a precious stone, classed by Pliny among the numerous varieties of the carbuncle216; for however perplexed and unintelligible his account of the carbuncles may be, and however much the readings in the different copies may vary, we still know that he describes a stone which was very hard; which was of a purple, that is a dark violet colour, and used for seals; and which, when heated by the beams of the sun, or by friction, attracted chaff and other light bodies. Had Pliny told us that it at first attracted and then repelled them, no doubt would remain; but he does not say so, nor do his transcribers Solinus and Isidorus217.

A much later account of a stone that, when rubbed, is, like the magnet, endued with an attractive power is to be found in a passage of John Serapion, the Arabian, pointed out to me by Professor Bütner218. This stone indeed cannot with much probability be taken for the tourmaline, as all precious stones, when heated, have the same property; but it is worthy of remark, that, like the lyncurium of the ancients, it belongs to the hyacinths, the colour of which many of the real tourmalines have; and among those of the island of Ceylon there are, perhaps, some which ought to be classed among the hyacinths, rather than among the schorls.

The real tourmaline was first brought from Ceylon, and made known by the Dutch, about the end of the seventeenth or beginning of the eighteenth century. It is commonly believed that the first account of it ever published is that to be found in the Memoirs of the Academy of Sciences at Paris for the year 1717; but it appears that fuller and more accurate descriptions of the properties of that stone were given in German works ten years before. The earliest information that I know respecting it is in a book now almost and justly forgotten, entitled Curious Speculations during Sleepless Nights219. In a passage, where the author, speaking of hard and glassy bodies which attract light substances, affirms that this property is not magnetic, he says, “The ingenious Dr. Daumius, chief physician to the Polish and Saxon troops on the Rhine, told me, that in the year 1703 the Dutch first brought from Ceylon in the East Indies a precious stone called tourmaline, or turmale, and named also trip, which had the property, that it not only attracted the ashes from the warm or burning coals, as the magnet does iron, but also repelled them again, which was very amusing; for as soon as a small quantity of ashes leaped upon it, and appeared as if endeavouring to writhe themselves by force into the stone, they in a little sprang from it again, as if about to make a new effort; and on this account it was by the Dutch called the ashes-drawer. The colour of it was an orange-red heightened by a fire colour. When the turf coals were cold, it did not produce these effects, and it required no care like the magnet. I have considered whether it would not attract and repel the ashes of other burning coals as well as those of turf; and I have no doubt, that, if heated, it would attract other things besides ashes.”

This whole passage has been inserted word for word, without variation or addition, and without telling the source from which taken, in a book perhaps equally forgotten, called Observationes curioso-physicæ, or Remarks and Observations on the great Wonders of the World, by Felix Maurer, physician220. This thick volume is entirely compiled from a number of works, the names of which are not mentioned.

      In the Catalogue of the collection of natural curiosities belonging to Paul Hermann, which were sold at Leyden in June 1711, I find, among the precious stones, Chrysolithus Turmale Zeylon. Though no description is added, it cannot be doubted that our tourmaline is meant. From this however we learn that the name together with the stone came to us from Ceylon, as Watson has remarked. We learn further, that the stone was at first considered as a chrysolite, and perhaps it may be mentioned under this name in the old accounts of Ceylon. Hermann, whose service to botany is well known, was in that island from 1670 to 1677; and it might be presumed, from his spirit of inquiry, that, had he known this stone, he would somewhere or other in his works have taken notice of its properties: but I find no mention of it either in his Cynosura Materiæ Medicæ, or in Musæum Zeylonicum.

In the year 1719 the Academy of Sciences at Paris announced in their memoirs for 1717, that in the latter year M. Lemery had laid before them a stone found in a river in the island of Ceylon, which attracted and repelled light bodies221. It is there called a small magnet, though some difference between the two stones was admitted; but the German naturalist before-mentioned, denies that the tourmaline is endowed with magnetic virtue. It is however very remarkable, that though it is said, in the Memoirs of the Academy, that it has the power of attracting and repelling, no mention is made that it acquires that property, only after it has been heated, which is expressly remarked by the German. Those therefore who wish to ascribe to the ancients a knowledge of the tourmaline may say, If the editor of the Memoirs of the French Academy could forget this circumstance, is it not highly probable that Theophrastus might have forgot it in describing the lyncurium; Pliny, in describing the carbuncle; and Serapion, in describing his hyacinth?

      After this period the tourmaline must have been very scarce in Europe; for when Muschenbroek made his well-known experiments with the loadstone, and spared no labour to carry them to the utmost extent, he was not acquainted with the nature of the tourmaline, which, according to the account given of it by the Academy at Paris, he considered as a magnet, as he himself says in the preface to his first dissertation, published in 1724.

About the year 1740 however some German naturalists made experiments with this stone, in order to discover the real cause of its attractive property. These may be seen, under the article Trip, in the well-known Dictionary of Natural History which is often printed with Hübner’s preface; but I do not know to whom the honour belongs of having first investigated the properties of this stone. As the above dictionary is common, I shall give here only a very short extract from it:—“This stone was brought to Holland by some persons who had travelled in India, from the island of Ceylon, where it is found pretty frequently among the fine sand near Columbo, and sold to the German Jews. These caused it to be cut thinner, and the price of it soon rose to eight and ten Dutch florins. It has been since much dearer; but at present it is cheaper. It attracts not only ashes, but also metallic calces: it however attracts more easily and with greater force those which have been formed by means of sal-ammoniac, or the spirit of that salt. It acquires its attractive power only after it has been moderately heated; for when cold or heated to a greater degree it produces no effect, which the author ascribes to its being united with martial sulphur. The chrysolites and other precious stones of the island do not possess the same property.” As the author quotes the Laboratorium Zeylonicum, СКАЧАТЬ