54 
Mr. Davy’s Experiments on 
moisture and oxygene visibly separated, cannot be conceived 
to be as much as T r T or ~ of the weight of the ammonia ; I 
resolved to investigate more precisely, than I had reason to 
think had been hitherto done, the specific gravities of the 
gasses concerned in their dry state ; and the very delicate 
balance belonging to the Royal Institution, placed the means 
of doing this in my power. 
Nitrogene, hydrogene, and ammonia, were dried by a long 
continued exposure to potash, and were very carefully 
weighed. Their relative specific gravities proved to be at 
30.5*°' barometer, 51 0 Fahrenheit’s thermometer. 
For nitrogene, the 100 cubical inches - - 29.8 grains. 
For hydrogene, ditto. - - - 2.27 
For ammonia - - - 18.4 
Now, if these data be calculated upon, it will be found, that 
in the decomposition of 100 of ammonia, taking even the 
largest proportions of gasses evolved ; there is a loss of —g,* 
and if the smallest proportion be taken the loss will be 
nearly T r -. 
These results and calculations agree with those that I have 
before given, and with those of Dr. Henry. 
The lately discovered facts in chemistry, concerning the 
important modifications which bodies may undergo by very 
slight additions or subtractions of new matter, ought to ren- 
der us cautious in deciding upon the nature of the process of 
the electrical decomposition of ammonia. 
* 100 of ammonia at the rate of 185, will give 136.9 of hydrogene, weighing 3.1 
grains, and 48.1 of nitrogene weighing 14.33 grains ; but 18.4™ 17.4 ra 1, and at 
the rate of 180, 133 of hydrogene weighing 3.01 and 47 of nitrogene, weighing 14 
and 18.4 — 17 — 1.4. 
