fRETENDED NEW METAL; PALLADIUM. fOl 



fliould difpofe us to admit it when accompli (lied. Every che- 

 mift well knows that fimilar fixations of volatile fubftances are 

 not uncommon If an ore containing fulphur, or arfenic, or 

 antimony, be gently roafted, a great part of thofe volatile bo- 

 dies is driven off; but, if a filling heat be fuddenly applied, Inftances; the 

 the mafs unites in fuch e manner that a very fmall fliare of ^^jpi^^^^ arfenic, 

 them efcapes. Mr. Hatchett has inftanced an artificial com- antimony. 

 bination of gold and arfenic, from which he could not expel 

 the latter metal, by any degree of heat. Yet arfenic, though 

 lefs fufible, is not much lefs volatile than mercury, I will alfo 

 add a cafe ftill more in point; viz. the combination of arfenic 

 and platina, which is not to be broken by a fufing heat. 



An example of this fa6t, occurs again in water. The lique- Mercury havhig 

 faction or folidification of two gafes to produce water, by a J.o^b?ieTJith 

 lofs of caloric, never (hocks our mind, becaufe it is familiar to platina, may be 

 us. We cannot fay what lofs of caloric may be fuftained by '" ^"^ *""^^ 



•^ . . ■' . ■' fituation as ox- 



mercury, in order to unite with platina ; or how far the pre- ygen jn many 

 fence of the latter may contribute to expel caloric from the oxides; viz. not 

 former. We know too, that at any temperature, without the ^^^^ ^eat, and 

 aid of a combuftible body, to a6l as a reductive, we have not perhaps by few 

 been able to difunite the laft portions of oxygen, from the ^ 

 oxides of iron or of manganefe. Yet, in the ufual method of 

 ' reducing a metallic oxide, the oxygen is furrounded by a much 

 greater quantity of caloric than is necelTary to convert it into 

 gas. Every fixation of a volatile fubftance is analogous to the 

 prefent queftion; and they whofe minds have taken alarm 

 ' from the novelty of the fa6l, may thus be familiarized with the 

 neceflity of admitting it. 



But, it may be obje6led, in the inftances of iron or manga- Metals may 

 nefe, oxygen is combined with a combuftible body, and re- <^ombine toge- 



. , • . 1 1-11 1 ri ^ • r^, . therbyanaffi- 



tamed m it by a decided and powertul affinity. There is no nity comparable 



reafon to fuppofe that fuch an affinity may not exift among *° ^^^^ °' ^ 

 metals. We have been forced to acknowledge it, in a few gen, 

 cafes, among the earths; and, from the profound and faga- 

 cious refearches of Mr. BerthoUet, we have learned many new 

 fa6ls, that promife us a rapid increafe of knowledge. I (hall 

 beg leave to add a few examples, which are taken from that 

 clafs of bodies to which the fubje6t of the prefent Paper be- 

 longs, and (how that the metals obey the general law of mu- 

 tual attra6tion. 



CTo be concluded in our next.) 



