90 On the Combinations of different Metals, &c. 



vessel, and this operation continued for an hour or two 

 affords a pure or nearly pure butter of bismuth. Tiius pre- 

 pared, it is of a grayish white colour, opake, uncrystallizt-d, 

 and of a granular texture. Tn a glass lube, with a very 

 small orifice, it bears a red heat without subliming. 



As a hydrosulphuret of bismuth is produced when the 

 butter of bismutli is heated with the hydrosulphuret of 

 potash, and as this hydrosulphuret, like that of aiitunonv, 

 affords, when decomposed bv heat, a sulpliuret and water, 

 I have applied the same mode of analysis to this compound 

 as to the last. 



Fifty-five grains of butter of bismuth were decomposed 

 in a warm solution of hydrosulphuret of potash. The dark 

 brown hydrosulphuret of bismuth thus formed, and not 

 dissolved, was collected on a filter; the hydrosulnhuretled 

 solution was decomposed by muriatic acid, the slight pre- 

 cipitate of hydrosulphuret produced was added to the first 

 portion, and the whole was well washed, dried, and heated 

 to redness in a glass tube ; the su!phuret of bismuth thus 

 obtained, fused into one mass, weighed 44*7 grains. I 

 had previously ascertained the proportion of metal in this 

 sulphuret, and found it to be 81 '8 per cent. 44*7 grains 

 of sulphuret, or 35 grains of the butter, must therefore 

 contain 36'5 grains of bismuth; and hence, 100 of bis- 

 inuth appear to consist of 



33*6 chlorine 



66*4 bismuth 



100 



The butter of bismuth may be called bismuthane. 



Among the preceding combinations of the metals and 

 chlorine, there is a surprising difference in respect to vola- 

 tility and fusibility. Iron and manganese, two difficultly 

 fusible metals, form with chlorine readily fusible com- 

 pounds, and a combination of the former metal and chlorine 

 is even volatile ; the compounds of tin and chlorine, and of 

 chlorine and antimony, are very volatile substances, though 

 the metals themselves are fixed at very high temperatures; 

 on the contrary, the combinations of chlorine with bismuth, 

 zinc, and lead, do not exceed in fusibility, indeed are not 

 quite so fusible as the metals themselves. I can offer no 

 explanation of these phaenomena. 



Another singularity attending the liquid fuming com- 

 pounds of chlorine, such as the liquor of Libavius, the 

 fuming liquor of arsenic, and the oxymuriats of sulphur 

 and phosphorus, is, that they do not become solid at low 



temperatures. 



