50 
Mr. Davy's Experiments on 
gene produced. Thirteen cubical inches of gas, were evolved 
in the first operation ; which consisted of nearly 1 cubical inch 
of ammonia, 4 of nitrogene, and 8 of hydrogene. The por- 
tion of gas given off in the second operation, equalled 3 .6 
cubical inches ; which consisted of 2.5 hydrogene, and 1.1 
nitrogene. The potassium produced in the operation, was 
sufficient to generate 3.1 cubical inches of hydrogene. 
As the iron in these experiments had been heated to intense 
whiteness, and must have been very soft ; it was not impossi- 
ble, considering the recent experiments of M. Hassenfratz,* 
that the loss of so large a portion of potassium, might depend 
upon an intimate union of that body with iron, and its pene- 
tration into the substance of the tube. This idea is counte- 
nanced by another experiment of the same kind, in which the 
heat was raised to whiteness, and the barrel cut into pieces 
when cool : on examining the lower part of it, I found in it a very 
thin film of potash ; but which I conceive, could scarcely equal 
a grain in weight. The pieces of the barrel were introduced 
under a jar inverted in water ; at the end of two days nearly 
2.3 cubical inches of hydrogene were found to be generated. 
In the experiments detailed in page 53 of the last volume 
of the Transactions, a loss of nitrogene, and a production of 
hydrogene was perceived in a case in which the residuum 
from a portion of fusible substance, which had been exposed 
to a low red heat, was distilled in a tube of platina ; but in this 
case the residuum had been covered by naptha, and it is pos- 
sible that ammonia might have been regenerated by hydro- 
gene from the naptha, and absorbed by that fluid ; and apart 
of the hydrogene might likewise proceed from the decompo- 
* Journal des Mines. Avrili8o8.p 275, 
