44 Mr. Davy’s Lecture on some new analytical Researches 
eight cubical inches and a half of hydrogene gas : and eight 
grains from the same mass, by their action upon ammonia, 
produced eight cubical inches and one eighth of inflammable 
gas. This difference is inconsiderable, yet I have always 
found it to exist, even in cases where the ammonia has been 
in great excess, and every part of the metal apparently con- 
verted into the olive coloured substance. 
No other account of the experiments of M. M. Gay Lussac 
and Thenard has, I believe, as yet been received in this coun- 
try, except that in the Moniteur already referred to ; and in 
this no mention is made of the properties of the substance 
produced by the action of ammonia on potassium. Having 
examined them minutely and found them curious, I shall ge- 
nerally describe them. 
1. It is crystallized and presents irregular facets, which are 
extremely dark, and in colour and lustre not unlike the prot- 
oxide of iron ; it is opaque when examined in large masses, 
but is semi-transparent in thin films, and appears of a bright 
brown colour by transmitted light. 
2. It is fusible at a heat a little above that of boiling water, 
and if heated much higher, emits globules of gas. 
3. It appears to be considerably heavier than water, for it 
sinks rapidly in oil of sassafras. 
4. It is a non-conductor of electricity. 
5. When it is melted in oxygene gas, it burns with great 
vividness, emitting bright sparks. Oxygene is absorbed, nitro- 
gene is emitted, and potash, which from its great fusibility 
seems to contain water, is formed. 
6 . When brought in contact with water, it acts upon it with 
much energy, produces heat, and often inflammation, and 
