210 M. C. Lea :—Chemical Contributions. 
Art. XXVI—Chemical Contributions ; by M. C. Lama. 
4. On the Action of Nitric Acid on Picramic Acid. 
Ow this point very conflicting statements have been made. 
Girard, and Pugh, respectively state that picric acid is reproduced 
ic 
Wohler stated that his nitrohematic acid (now known to be 
identical with picramic) was not reconverted to picrie acid by 
The following were the reactions observed. 
Picramic acid readily dissolves in strong nitric acid to a dark 
brown solution. By 15 minutes boiling this becomes clear bright 
red. If then saturated with potash, quantities of nitrate of pot- 
ash crystallize out, with much brown varnish, but no trace of 
picrate. After one hour’s boiling the color of the solution 1s 
considerably lighter—the results much the same. : 
After four hours boiling the color of the liquid was bright 
from the former, bright yellow, and colored intensely deep T * 
by cyanid of potassium after previous supersaturation wit 
ammonia. But treated with sulphydrate of ammonia, it ie a 
greenish brown with production of a greenish precipitate. The 
presence of oxalic acid could not be detected. 
