-0*8 Ohfervaitons fl«, thefuppofed Afagnti'tc Properf;^ -of NicieL 



cither of thofe metals perfedly pure, anfwered the purpofe as well as thofe made of tlie 

 ufual fubftance. In tlic fummer of 1798 I was witnefs to feme experiments, performed 

 at the Eco/e des mines', to (hew that feveral pieces of both, which had been reduced to the 

 metallic (late, in the laboratory of that eftablifliment, and which were magnetic, were to- 

 tally exempt from iron. The experiments were conduced by Monf. Vauquelin, and were 

 as follows : fome magnetic bits of each of thofe metals were dilTolved in an acid, and iron 

 was, in vain, looked for by the delicate tefts of an infufion of gall nuts, and a folution of 

 pru(riate of pot-afli. Hence it was reafonable to conclude that no iron was prefcnt, and 

 that nickel and cobalt really are magnetic of themfelves, and independently of alloy. 

 . If I have obtained nickel \n its metallic ftate, and in no way attradlable, it was not iu 

 performing experiments with thisdiredt view, for fo fully was 1 convinced of the accu- 

 racy of thofe I had witneflTed in Paris in 1798, that I entertained no doubt upon the fub- 

 jeft. I had an acid folution of impure oxide of nickel, which I precipitated by ammonia, 

 for the purpofe of procuring fome pure nickel which I happened to want. I filtered im- 

 mediately, and fuffered the ammoniacal folution to (land fome days in a well (lopped bottle. 

 The liquor remained of the ufual colour, but a bluei(h precipitate, which likewife I fepa- 

 rated by the (iltre, had been formed at the bottom. The alkaline liquor, which had palTed 

 clear, was evaporated ; and the oxide of nickel, which fell as the ammonia was volatilized, 

 was colle<3;ed, waflied, dried, and treated with a proper flux, in a HeDTian crucible, and 

 in a forge capable of giving a (Irong heat. By this procefs I obtained a refult which was 

 nickel, fo unattra£lable, that prefented as near as a (leady hand could hold it, to a very 

 delicate magnet, fupported on a cork floating on water or on mercury, no vifible influence 

 took place upon the magnet. A bit of the nickel, diflblved in an acid, exhibited, as may 

 ■ht well fuppofed, no traces of iron. 



Its fpecific gravity, taken by the Count de Bournon, at a balance fenfible to the -^l^ of a 

 grain, and at the temperature of 60, was 7,3806, a fpecilic gravity much inferior to that 

 which Bergman had found, 9,0000 ; and even to that.given by Monf. de Morveau, 7,8070; 

 hence it would appear that the prefence of iron tends to increafe its denfity. Its fufibility 

 I could not afcertain, having no pyrometer. Its malleability is certainly greater than that 

 of zinc. Its colour, like fome of the alloys of filver and copper, of a very pale red. Its 

 hardnefs conCderable, and its fradlure grainy and uneven. Several of my chymical friends 

 in this country have witnefled the ineflicacy of this nickel in attracting the magnetic needle ; 

 and Profeflbr Pi£let of Geneva was fo good as to take fome of it to the chymifts in France, 

 to convince them of the error which they are under, with regard to this property in 

 nickel. 



It does not appear from the refults of the experiments to which, as I mentioned, I was 



J witnefs in 1798, that there was any inaccuracy in the mode of operating; but merely, 



\\ui magnetifm is a re-agent more powerful to dete£l minute portions of iron, when in its 



metallic (late, than is either a folution of gall nuts, or of pruflfjate of pot-afli, to difcover 



4 its 



