48 Mr. Davy’s Lecture on some new analytical Researches 
of ammonia. In one instance, in which I heated the fusible 
substance from nine grains of potassium, in a retort that had 
been filled with mercury in its common state of dryness, I 
obtained seven cubical inches of ammonia as the first product ; 
and in another experiment which had been made with eight 
grains, and in which moisture was purposely introduced, I ob- 
tained nearly nine cubical inches of ammonia, and only four 
of the mixed gases. 
I am inclined to believe, that if moisture could be intro- 
duced only in the proper proportion, the quantity of ammonia 
generated, would be exactly equal to that w r hich disappeared 
in the first process. 
This idea is confirmed by the trials which I have made, by 
heating the fusible substance with potash, containing its water 
of crystallization, and muriate of lime partially dried.* 
In both these cases, ammonia was generated with great 
rapidity, and no other gas, but a minute quantity of inflam- 
mable gas, evolved, which was condensed by detonation with 
oxygene with the same phenomena as pure hydrogene. 
In one instance, in which thirteen cubical inches of ammonia 
had disappeared, I obtained nearly eleven and three quarters 
by the agency of the water of the potash ; the quantity of 
inflammable gas generated, was less than four tenths of a 
cubical inch. 
In another, in which fourteen cubical inches had been 
* If water, in its common form, is brought in contact with the fusible substance, 
it is impossible to regulate the quantity, so as to gain conclusive results, and a very 
flight excess of water causes the disappearance of a very large quantity of the ammo- 
nia generated. In potash and muriate of lime, in certain states of dryness, the water 
is too strongly attracted by the saline matter to be given off, except for the purpose 
of generating the ammonia. 
