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quarter the lining of the furnace the lump between a pair of pinmelted all down, and formed mas- cers; besides, the surface of this ses of glass which choaked the lump being tarnished and brown, noses of the bellows; the crucible it was thereby the fitter to absorb was also vitrified, but the obstinate the solar rays; whereas the meplatina exhibited only fome grains, tallic brilliancy, which these grains perfectly round, as white as silver, naturally have, when separate, prowhich seemed to have undergone mised less success. a perfect fusion : yet a slight stroke The platina thus exposed to the of a hammer reduced them to pow. focus of the speculum, first turned der.
to a blueilh white, cafting off by After having in vain employed fits very lively sparks, and diffufthe several means we have recited, ing a very sensible fume ; finally, there still remained one which pro- in about a minute it was in a true mised fome degree of hope, and fusion ; but with this particular, the rather worth trying, as it had that the melted parts did not drop never been made use of by any to the ground, but attached them chemist in the examination of pla- selves to those next the limits of tina ; this was to expose the pla- the field of the focus. tina to the focus of a good burning Thosé melted parts shone like fpeculum.
silver, and their surface was roundThe fpeculum Mr. Macquered, bright, and polished. Being used, was of glass, its diameter hammered on a small steel anvil, two and twenty inches, and the they were flatted to a thin plate distance of its focus twenty-eight without any cracking ; in a word, inches. In half a minute it melt- they afforded fufficient marks of ed a gun-flint, and changed it into malleability, not only far beyond transparent glass; vitrified Hef- what they had before the fusion, fiancrucibles and fragments of but even such as gave hopes that glass-house pots in three or four they might be spread as thin as the seconds; made forged iron fume, leaves of gold or filver. melt, boil, and turn to a vitref. Mr. Macquer having examined cent' fcoria' in an instant; nay, the properties which the action of melted the gypseous stones, which fire discovers in platina, submitted Mr. Pott seems to regard as un
this metal to the action of other fusible.
folvents. Of all the acid menThese effects, with several others, ftruums aqua regalis alone proved invited Mr. Macquer to submit a solvent of platina, at least whilst platina to such an agent; he did it remained in its natural state. so, and here follows the result.
This diffolution produces vari. The platina he used is that said ous phænomena. It requires a above to have been exposed to a great quantity of aqua regalis, and glass-house fire, and whose grains is effected much more easily by a were agglutinated together; as fand heat than without it. they were then in a solid mafs, Macquer takes notice that the
prethey could be the more convenient cipitates of platina made with valy exposed to the focus by holding latile and fixed alkalis, have not
Mr. that red colour which Dr. Lewis fult which at first seemed no more attributes to them in geņeral, ex
successful than that of Dr. Lewis ; cept when no more of those alka- but a repeated examination opened lis is used than what is barely fuf- to him very different properties ; ficient to faturate the acid ; which the platina, instead of increasing obfervation led him to every na- in weight, as Dr. Lewis had obtural explanation of the colour the served, was found to have lost a precipitate assumes in the case we sixteenth part; it was moreover have been speaking of.
very extensible under the hammer. It has been long known in che. The same platina cupelled, and miftry, that precipitates always then dissolved in aqua regalis, shewcarry down along with them parted not the least marks of any reof the dissolvent
and of the preci- maining lead. pitant: this truth, which is abun- The whole of Mr. Macquer's dantly sensible in the precipitate observations, compared with what of platina, afforded Mr. Macquer other chemists have delivered about the means of accounting for feve this metal, seems to establish the ral phænomena which Dr. Lewis following matters of fact. That had noticed in the precipitation of platina is a third perfect metal, as platina, though that learned che- fixed, as indestructible, as unal. mist has not explained them. terable as gold and silver; that it
The red precipitate of platina, is not absolutely unfusible; that mixed with a fux composed of there is even room to hope, that calcined borax, cream of tartar, by mixing it with destructible me. and white glass, after being ex- tals, and employing a sufficiently poled to a forge heat, produced a durable and intense heat, it may lump of the complexion of platina, be fluxed in large furnaces. The with all the resemblance of a me- attempts that have hitherto, or tal that had been well melted. Als may be hereafter made with this though this lump had not the fatis- view, cannot be too much apfactory tokens of malleability, yet plauded; it is easy to apprehend there is room to believe that the of how great utility in arts a mefusion had not been sufficiently tal may prove which refifts the acperfect : this is a point which Mr. tion of air, water, fire, sulphur, Macquer intends to examine here- acids, and the voracious metals, after, as also the vitrescent matter, and had the strength and hardness into which the precipitate of pla- of iron combined with all these tina was converted, after the ope- qualities. Wise motives have deration of the speculum,
termined the Spanish ministry to The cupellation of platina by interdict the working of their plalead is also one of the objects tina mines, and to prohibit the which have been examined by Dr. commerce of it; however, the Lewis, and wherein Mr. Macquer lights that chemistry has already proposed to surmount the difficul- let us into concerning this metal, ties which that ingenious gentle. may make us easy as to any abuses man seems to have met with : this that may be made of it, and afford operation gave Mr. Macquer a Te hopes, that it may in due time be
he more easily procured, and far- had ascended and vegetated along her experiments made upon it. those pieces of oak-wood (the
wood having served as a preci
pitant) and formed thrubs on them. 'nstance of the regeneration of me- What seems very singular, is, that
tals, from the last volume of the all those shrubs have resumed with Mem oirs of the Royal Academy time the metallic form. M. Helof Sciences at Paris.
lot, to whom we are indebted for
this observation, presented to the THE question concerning the Academy a piece of this wood,
regeneration of metals in which had been sent to him from nines, is one of the most impor- Cheify. The metallic vegetation ant points of natural philosophy. is seen plainly on it, and it is now Some metallurgifts are of opinion kept in the cabinet of the king's that they are regenerated; others, garden, as a very curious article of that they are not. In the copper- natural history. mine of Cheisy, near St. Bel, in How many questions of natural the province of Lyonnois, there is philosophy, on which we are now found a metallic vegetation which divided in opinion, would have appears greatly in favour of the been solved if our observations were affirmative. In this mine is a ca- of a more ancient date ! Let us vern or gallery upwards of two therefore endeavour to be more ferhundred feet long : it is a work of viceable to posterity than the anthe Romans ; and the pieces of cients have been to us ; and, if we wood that serve to sustain the roof, cannot transmit to them a true picare still in a pretty good condition. ture of this world, let us at least, The copper of this mine, proba- if possible, leave behind us the ne bly dissolved by some vitriolic acid, cesary materials for forming it.
An account of the Spanish fishery the rest are divided among the crew
Chitherto unnoticed by other na- according to their merit :
in the fishery, half á fhare, or a
quarter, according to his abilities. HE number of vessels em- The patron, or master of the bark,
ployed in this fishery amount fhares equally with the able fifherto about 30; they are from 15 to men, and the owners allow him al50 tons burthen ; the smallest carry so one share out of their's for his 5 men, and the largest 30. They trouble in taking care of the bark. are all built in the islands, and The place on the coast of Barnavigated by the natives. Two of bary where they go to fish, is accordthese belong to the island of Palma, ing to the season of the year. This four to Teneriffe, and the rest to fishery is bounded on the north by Canaria. Porto de Luz in that the southern extremity of Mount island; is the place from whence Atlas, or by the latitude of 29 dethey fail for the coast.
north and on the south by The method of fitting out a bark Cape Blanco, in the latitude of 20 for the fishery is this; the owners degrees 30 minutes north : the furnih a vessel for the voyage, and whole length of the sea-coast fo put on board her a quantity of salt bounded is about 600 miles. In sufficient to cure the fish, with all this extensive tract there is no bread enough to serve the crew for town, village, or settled habitathe whole voyage. Each man car- tion; the few wandering Arabs ries his own fishing tackle, which who frequent this part of the world consists of a few lines, hooks, a live in tents, and have neither little brass-wire, a knife for cut- 'nats, barks, nor canoes: the ting open the fifh, and one or two king of Morocco's cruizers never stout fishing-rods. If any of the venture so far to the southward ; crew carry wine, brandy, oil, vi- for were they to attempt such a negar, pepper, onions, &c. it must thing, it is not probable they would be at his own expence, for the be able to find the way back to their owners furnish no provision but own country, so that the Canaribread. The net sum arising from ans have nothing to fear from that the sale of the fish, after deducting quarter. In the spring season, the the expence of the salt and bread fishermen go to the coast to the before mentioned, is divided into northward, but in the autumn and shares, a certain number of which winter to the southward ; because are allowed to the owners for their in the spring the fish frequent the expence in fitting out the vessel ; coasts to the northward, and after
wards go gradually along the shore serves as well as the tafsarte for bait: to the southward.
There is another fort of bait callThe first thing the fishermen set ed cavallos, or little horse macabout when they arrive on the karel, but something more flat coast, is to catch bait; this is done and broad; it is about a span long, in the fame manner as we do trouts and is catched with an angling rod with a fly, only with this differ- and line with a very small hook, ence, that the rod is thrice as baited with almost any thing that thick as ours, and not tapered comes to hand. When a bark has away so much towards the point. got a sufficient stock of bait, the The line is made of fix small brass leaves her boat, with five or fix wires, twisted together : the hook men, near the shore, to catch tasis about five inches long, and is farte and anhoua, and runs out to not bearded ; the shaft is leaded sea a good distance off, until she so as it may lie horizontally on gets into fifteen, twenty, thirty, the surface of the water ; and the forty, or perhaps fifty or fixty fahook is covered with a fifh's skin, thoms depth of water, where the except from where it bends, to anchors, and all the crew heave the point ; then getting within a their lines and hooks overboard, quarter or half a mile of the shore, baited with tafsarte, anhoua, &c. they carry so much sail as to cause and fish for famas, or bream as we the bark to run at the rate of four call them, and for cherney, or cod. miles an hour, when two or three The lines are all leaded, in order men throw their lines over the to cause the hooks to link near to stern, and let the hooks drag along the bottom of the sea, where these the surface of the water ; the filh, fish swim. When a bark is so for taking the hooks for small fish, tunate as to meet with fine weasnap at them, and, when hooked, ther, and is well provided with the fishermen swing them into the bait, she will be able to complete barks with their rods. The Ca- her cargo in four days. This I narians call these fish tassarte : they have often had opportunity to obhave no scales, and are shaped like serve. But as the trade or northmackarel, but as large as salmon ; east wind commonly blows fresh they are exceeding voracious, and on that coast, the barks only answallow all the hook, notwith- chor in the offing about mid-day, standing its being so large. If it when there is a lull between the was bearded, there could be no land and sea breeze ; and when such thing as extracting it without this last-mentioned wind begins to cutting open the fish. I have seen blow fresh, they weigh their anthree men in the stern of a bark chors, stand in to shore, and come catch an hundred and fifty tafsarte to an anchor in some bay, or under in half an hour. It sometimes a head-land, and then the crew fall happens that a bark will complete to work, clean and salt the fish her lading in these fish only. “An- which they catched that day. By other fort of fish, which these peo- the time this is done, it is about ple call an oua, is taken in the five or six o'clock in the evening, same manner ; this is something when they go to dinner or supper, bigger than a large mackarel, and for they make but one meal the