447 
oj carbon and hydrogen, ^c. 
carbon, and hydrogen; but I reserve the consideration of 
these, and of other similar compounds, to another oppor- 
tunity. 
Iodine appears to exert no action upon the substance in 
several days in sun-light ; it dissolves in the liquid in small 
quantity, forming a crimson solution. 
Potassium heated in the liquid did not lose its brilliancy, or 
exert any action upon it, at a temperature of i86^ 
Solution of alkalis, or their carbonates, had no action 
upon it. 
Nitric acid acted slowly upon the substance and became red, 
the fluid remaining colourless. When cooled to 32°, the 
substance became, solid and of a fine red colour, which dis- 
appeared upon fusion. The odour of the substance with the 
acid was exceedingly like that of almonds, and it is probable 
that hydrocyanic acid was formed. When washed witli 
water, it appeared to have undergone little or no change. 
Sulphuric acid added to it over mercury exerted a moderate 
action upon it, little or no heat was evolved, no blackening took 
place, no sulphurous acid was formed ; but the acid became 
of a light yellow colour, and a portion of a clear colourless 
fluid floated, which appeared to be a product of the action. 
When separated, it was found to be bright and clear, not 
affected by water or more sulphuric acid, solidifying at about 
34°, and being then white, crystalline, and dendritical. The 
substance was lighter than water, soluble in alcohol, the 
solution being precipitated by a small quantity of water, but 
becoming clear by great excess.* 
• The action of sulphuric acid on this and the other compounds to be described, 
is very remakable. It is frequently accompanied with heat ; and large quantities of 
