of the 'Fixed Oils in contact mth Sulphur, 1*71 



hot alcohol and aether. This oil is in all probability the 

 sulphuret of odmyle Cg Hg Sg j but the small quantity in which 

 I have been able to obtain it, has prevented my performing 

 any analysis of it. 



The Flaiinum Compound. — When a solution of bichloride 

 of platinum is added to the alcoholic solution of the crude oil, 

 a yellow precipitate makes its appearance, which does not fall 

 immediately, but goes on gradually increasing for some time, 

 precisely as is the case with the allyle compound. The pro- 

 perties of this precipitate are not however perfectly constant, 

 but vary according to the portion of the oil employed to yield 

 it. That obtained from the more volatile portion has a fine 

 sulphur-yellow colour, but the less volatile oil gives an orange 

 precipitate. It is insoluble in water, sparingly soluble in 

 alcohol and aether. When heated it becomes black, an oil is 

 evolved smelling exactly like that obtained from the mercury 

 compound, and sulphuret of platinum is left behind, which 

 requires a high temperature to drive off all its sulphur, and 

 leaves metallic platinum as a silver-white mass. When treated 

 with hydrosulphuret of ammonia, it is converted into a brown 

 powder, exactly like that obtained under similar circumstances 

 from allyle. 



The analysis of the yellow compound has not hitherto given 

 results of a satisfactory character. I have found the amount 

 of platinum to oscillate between 43'06 and 49*66 per cent. 

 The former of thes'e was obtained from the most volatile oil, 

 the latter from that which boiled between 300° and 400° F., 

 and intermediate results were obtained at intermediate tem- 

 peratures. T!ie results obtained from the oil which boiled at 

 a high temperature were remarkably constant; thus I have 

 found, in different experiments, 49*00, 49*51, and 49*66 per 

 cent, of platinum, which appear to indicate the presence of 

 some compound of rather sparing volatility. The precipitate 

 obtained from the most volatile oil appears to be that corre- 

 sponding to the mercury compound which has just been de- 

 scribed. Of it I have been able only to perform a very incom- 

 plete analysis, which is insufficient to establish its constitution, 

 especially as it is impossible to ascertain whether it is a homo- 

 geneous substnnce. As the results, however, approximate to 

 a formula analogous to that of the mercury compound, I give 

 the details, such as they are. 



["9*155 grains of the platinum compound gave 

 ■< 7*474 ... carbonic acid, and 

 1^3*294 ... water. 



5*701 grains gave 2*455 grains of platinum = 43*06 per cent. 



