BUNSEN ON THE CACODYL SERIES. 315 
MRRAELET frie ee ion cars|) Ss . 388dines, 
The correction of the oil receiver . 57°8 ... 
The specific gravity calculated from these data is 5°46, and it 
corresponds, as nearly as the nature of the experiment allows, 
with the supposition that the oxide and chloride have combined 
without condensation, viz. 
3 vols. Chloride of betel oe) (Rar58 
1 vol. Oxide of cacodyl. . . 7°83 
Pha! _ 5-35 
4 
The characters of this basic compound correspond in general 
so closely with those of the neutral chloride, that I cannot do 
better than refer back to that section. It differs from the neu- 
tral compound in emitting a less disagreeable odour, and white 
vapours in contact with the air. It boils at about 109° C. 
13. Basie Bromide of Cacodyl. 
This substance also agrees very closely with the correspond- 
ing chlorine compound, and is obtained in a similar manner. It 
smokes in contact with the air, is yellow coloured, but becomes 
colourless on being heated, and on cooling again turns yellow. 
It evinces a most remarkable reaction on being heated with me- 
tallic mercury, which I could not unfortunately investigate, 
from want of a sufficient quantity of the material. The change 
it undergoes is not attended with any evolution of gas, but it 
is converted into a solid substance of a citron yellow colour, 
which is easily fusible. This substance can be converted into 
vapour without decomposition, and when boiled with water is 
changed into mercury and a fuming substance that passes off 
with the vapour. It is decomposed by a strong heat into mer- 
eury, subbromide of mercury, and a very disagreeable volatile 
body containing arsenic. As it agrees very closely in its other 
characters with the chloride, I shall confine myself to giving its 
analysis. The substance analysed was prepared by twice di- 
stilling a mixture of oxide of cacodyl and concentrated hydro- 
bromic acid, and purifying it in the same way as the chloride. 
In conducting the analysis with chromate of lead, the fore 
part of the combustion tube was filled with fine copper turnings, 
which prevented the bromide of copper passing over with the 
water. 
Y2 
