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

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СКАЧАТЬ were brought to perfection by Taliaisson, professor of law at Toulouse, and a young clergyman named De l’Isle.

      Alexander says more than once that this machine was invented at Sens in Burgundy, in 1690, by Dom Charles Vailly, a Benedictine of the brotherhood of St. Maur, and that he brought it to perfection by the assistance of a pewterer there, named Regnard. This account is in some measure confirmed by Ozanam; for he says expressly, that the first water-clocks were brought from Burgundy to Paris in 1693, and he describes one which was made of tin at Sens. Dom Charles Vailly was born at Paris in 1646, and died in 1726; he was celebrated on account of his mathematical knowledge, though he is known by no works, as he burned all his manuscripts206.

      Alexander, however, who was of the same order, seems to have ascribed to his brother Benedictine an honour to which he was not entitled; for Dominic Martinelli, an Italian of Spoletto, published at Venice, in 1663, a treatise written expressly on these water-clocks, which Ozanam got translated into French by one of his friends, and caused to be printed with his additions207. This translator says that water-clocks were known in France twenty years earlier than Ozanam had imagined. It appears therefore that they were invented in Italy about the middle of the seventeenth century, and that Vailly, perhaps, may have first made them known in France208.

      It may perhaps afford some pleasure to those who are fond of the history of the arts, to know that Salmon, an ingenious pewterer at Chartres in France, has given very full and ample directions how to construct and use this machine209. He is of opinion that the invention is scarcely a century old; and that these water-clocks, which are now common, were first made for sale and brought into use among the people in the country, by a pewterer at Sens in Burgundy. What this artist affirms, that they can be constructed of no metal so easily, so accurately, and to last so long as of tin, is perfectly true. I have however in my possession one of brass, which is well constructed; but it suffers a little from acids. Among the newest improvements to this machine may be reckoned an alarum, which consists of a bell and small wheels, like those of a clock that strikes the hours, screwed to the top of the frame in which the cylinder is suspended. The axis of the cylinder, at the hour when one is desirous of being wakened, pushes down a small crank, which, by letting fall a weight, puts the alarum in motion. A dial-plate with a handle is also placed sometimes over the frame.

      [A very ingenious application of the principle of the clepsydra, for the purpose of measuring accurately very small intervals of time, is due to the late Captain H. Kater. Mercury is allowed to flow from a small orifice in the bottom of a vessel, kept constantly filled to a certain height. At the moment of noting any event, the stream is interrupted and turned aside into a receiver, into which it continues to run till the moment of noting any other event, when the intercepting cause is suddenly removed. The stream then flows in its original course. The weight of mercury in the receiver, compared with the weight of that which passes through the orifice in a given time, observed by the clock, gives the interval between the events.]

      TOURMALINE

      The ancients, though ignorant of electricity, were acquainted with the nature of amber, and knew that when rubbed it had the power of attracting light bodies. In like manner they might have been acquainted with the tourmaline, and might have known that it also, when heated, attracted light bodies, and again repelled them; for had they only bethought themselves, in order to search out the hidden properties of this stone (which on account of its colour and hardness is very remarkable), to put it into the fire, they would have then seen it sport with the ashes. Some learned men have thought they found traces of the properties of this stone, in what the ancients tell us respecting the lyncurium, theamedes, and carbunculus. The fruit of my researches respecting this subject I shall here lay before the reader. All that we find in the ancients to enable us to characterize the lyncurium is, that it was a very hard stone, which could with difficulty be cut; that seals were formed of it; that it was transparent, and of a fiery colour, almost like that of yellow amber; that it attracted light bodies, such as chaff, shavings of wood, leaves, feathers, and bits of thin iron and copper leaf, in the same manner as amber; that the ancients procured it from Æthiopia, but that in the time of Pliny no stone was known under that name210.

      This information proves, in my opinion, that the lyncurium cannot be the belemnites, as some old commentators and Woodward have affirmed; for the latter has not the celebrated hardness and transparency of the former, neither has it the property of attracting light bodies, nor is it fit for being cut into seals. That opinion probably has arisen in the following manner: – the ancients supposed that the lyncurium was the crystallized urine of the animal which we call the lynx. As some belemnites contain bituminous particles which give them an affinity to the swine-stone, naturalists, when they have rubbed or heated yellow and somewhat transparent pieces of this fossil, have imagined that they smelt the fabulous origin of the lyncurium.

      Less ridiculous is the opinion of some old and modern writers, that the lyncurium was a species of amber. Theophrastus, however, the ablest and most accurate mineralogist of the ancients, would certainly have remarked this and not have separated the lyncurium from amber. Besides, the latter has not the hardness of the former, nor can it be said that it is difficult to be cut; for at present it is often made into various toys with much ingenuity. The opinion of Pliny is here of little weight; for it is founded, as ours must be, on the information of Theophrastus.

      Epiphanius, who considered the Bible as a system of mineralogy, but could not find the lyncurium in it, supposes that it may have been the hyacinth211. However ridiculous the cause of this conjecture may be, it must be allowed that it is not entirely destitute of probability; and I say with John de Laet, “The description of the lyncurium does not ill agree with the hyacinth of the moderns212.” If we consider 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 СКАЧАТЬ