French National Injlitute, 375 



their principal conftituent parts. The copper was eafily ob- 

 tained bv calcining a part of the bell metal, and thenthrow- 

 ino- it upon another part of the fame metal m a ftate of 

 fuLn ; but the fcori* produced, during this reduction, were 



lofl. . - , 



More inteHi2;ent cheniifts, and particularly Anfry, found 

 means to reduc^ the fcoriie, ;uid to reftore to commerce a 

 laroe quantity of tin, and a (till larger of copper. The tin, 

 however, obtained in the la(t refult has peculiar qualities ; 

 its frafture is ditTerent from that of common tin, it is harder, 

 and more cafilv broken. 



C. Sage has found means to imitate this tin, extrafted 

 from beU-metaljbv mixing with tin a little antimony ; and it 

 refults from his experiments, th;tt the latter metal alloyed 

 with tin, in the proportion of a tixlh part, unites with it in 

 fo intimate a manner that it is almo(l impoffible to feparate 

 it. C. Sace has no doubt then that the tin of bell-metal 

 contains a" certain quantity of it; but C Sage has afcer- 

 tained, byfeveral experiments, that it does not prevent.it 

 from being employed in making tin plate, and even for tin-, 

 ning veflcls. 



MINERAT.OGY. 



On the frefumed EffcQs of Galvamfm in the Mineral 



.Kingdom. 

 C. Guvton has given a defcription of a kind of ore of ari- 

 timonv lately difcos'ered in the province of Gallicia, ipeci- 

 mens of which had been tranfmiltcd to him by Don Anto- 

 nio Angulo, infpector general of the mines of Andalufia. 

 He foon found, by analvfis, that the metal in this ore is in 

 the ftate of oxide; but the (Irufture of the mineral, its in- 

 terior texture, its well characterized ftrise, plainly announced 

 that it was the padage from fulphuret to oxide, without an 

 alteration of form. It was therefore of importance to diito- 

 vcr how this change could have been effeded. 



C. Guyton trieil all the fimple or compound fubllances 

 which niitiht be prefumed to exilt in the bowels of the earth, 

 in order t'o imitate, in the laboratory, this labour of nature. 

 The fulphuret of antimony, both natural and artificial, re- 

 filled all his numerous attemptr^. He fuppofcd, very JLiftly, 

 that the decompolition f)f water ought to aft a pruicipal part 

 in this o;KTatinn, and even that it prefented the only means 

 of aceountiiio; for this alteration, (ince it ought at the iauic 

 time to furnilli oxvgen, and to take away the fnlphur by 

 means of the hydrogen ; but it was neceflary to diicover 

 what could have cktermined this decompofition. C. Guyton 

 contidcrs it a* the How and progrellive rel'ult of affinities put 



S 2 »ito 



