116 FORMATION OF HYDROCYANIC ACID, ETC. 
The products being collected in five separate parts all af- 
forded precipitates with, nitrate of silver, and these precipi- 
tates together weighed 0.65 of a grain. 
A fresh mixture of 
Spirit, sp. gr. .827, 100 grammes. 
Nitric acid, sp. gr. 1.3S4, 100 " 
Was gently heated in a large retort. Ebullition continued 
for two minutes, without the solution of nitrate of silver, 
into which the products were received, being rendered in 
the least degree turbid, but all at once there was so great a 
disengagement of hydrocyanic acid that the liquor instantly 
became milky and curdy. Unfortunately, a few seconds 
afterwards the retort broke, and the disengaged vapors 
were so highly charged with hydrocyanic acid, that the 
operator was obliged to quit the laboratory. The result of 
this experiment being inconclusive, M. Dalpaiz recom- 
menced it, taking the precaution to moderate the> action of 
the ingredients, by applying cold water to the retort. In 
this instance, the proportion of hydrocyanic acid disengaged 
was extremely small, and it is probable that none would 
have been formed if the action had been moderated still 
further. An elevation of temperature, therefore, is favor- 
able to the formation of hydrocyanic acid. 
M. Dalpaiz concludes his paper by observing that, of the 
numerous examinations he had made of specimens of com- 
mercial nitrous ether, with the view of ascertaining whether 
they contained hydrocyanic acid, nearly the whole had af- 
forded negative results; but that he had always found a 
considerable portion of formic acid. 
These researches of M. Dalpaiz have been very favorably 
reported upon by Messrs. Bernard, Derose, and Chatin. 
The experiments which these gentlemen undertook in con- 
nexion with their report, show that hydrocyanic acid is 
produced in notable quantity during the action of nitric acid 
on fatty bodies. They state also, that when one part of al- 
cohol and two parts of nitric acid are carefully distilled, the 
