36 On the Comlhiations of 



the ammonia-muriate of platina, it is possible to question 

 the accuracy of the preceding statements relative to the 

 super-sulphuret and super-phosphuret of platina; they 

 may perhaps be considered by some persons as compounds 

 of oxide of platina and the respective inflammable princi- 

 ples. From the experiments I have made on this metallic 

 salt, I consider it as a compound of platina, chlorine, 

 ammonia and water. But f>hoidd the facts I have to relate 

 be considered as inconclusive with regard to this point, 

 still, it appears to me, they can only be explained by ad- 

 mitting the constitution of the above combinations of 

 platina to be such as I have stated. 



When the ammonia-muriate of platina is exposed to a 

 dull red heat in a retort over mercury, (after being dried 

 for some time at a temperature above 212",) it is entirely 

 decomposed, the only products are nmriatic acid gas in 

 quantity, nitrogen gas, aqueous muriatic acid, sublimed 

 muriate of ammonia, and pure platina. Tn this experiment 

 the following changes may be presumed to take place. 

 One portion of the ammonia is decomposed, its nitrogen is 

 evolved, its hydrogen combines with the chlorine, to form 

 muriatic acid gas, one part of which assumes the gaseous 

 jitate, the other part is found in combination with the re- 

 sidue of the ammonia and with the water. This explana- 

 tion appears to be strictly conformable to facts ; at high 

 temperatures, ammonia is well known to be resolved into 

 hydrogene and nitrogene gases, and muriatic acid gas to be 

 formed from chlorine and hydrogene gases. As the gaseous 

 products are the same, and the general results precisely 

 analogous, whether the ammonia- muriate of platina be de- 

 composed alone, or in contact with sulphur or phosphorus, 

 the same explanation of the facts will equally apply to them all. 

 I have found that when metallic oxides are heated with 

 freshly sublimed muriate of ammonia, a quantity of water 

 is forrncd, ammoniacal gas is evolved, and compounds of 

 the metals and chlorine are obtained ; nor are these results 

 affected, even when the muriate jireviousjy contains water. 

 As in the case when a mixture of red precipitate and mu- 

 riate of ammonia are healed together, white precipitate ap- 

 pears to be the only combination of mercury formed, from 

 which calomel may be obtained by heating it with quick- 

 lime, it may not perhaps be unworthy the consideration of 

 the manufacturer, whether calomel and pure ammonia may 

 not be more oeconomically procured by these methods thaii 

 by those modes at present adopted. I merely throw this 

 out as a hint] it would be a happy circumstance, if any of 



the 



