45 
on the Nature of certain Bodies. 
evolves ammonia. When thrown upon water, it disappears 
with a hissing noise, and globules from it often move in a 
state of ignition upon the surface of the water. It rapidly 
effervesces and deliquesces in air, but can be preserved under 
naphtha, in which, however, it softens slowly, and seems 
partially to dissolve. When it is plunged under water filling 
an inverted jar, by means of a proper tube, it disappears in- 
stantly with effervescence, and the non-absorbable elastic fluid 
liberated is found to be hydrogene gas. 
By far the greatest part of the ponderable matter of the 
ammonia, that disappears in the experiment of its action upon 
potassium, evidently exists in the dark fusible product. On 
weighing a tray containing six grains of potassium, before 
and after the process, the volatile alkali employed having 
been very dry, I found that it had increased more than two 
grains ; the rapidity with which the product acts upon 
moisture, prevented me from determining the point with 
great minuteness ; but I doubt not, that the weight of the 
olive coloured substance and of the hydrogene disengaged 
precisely equals the weight of the potassium, and ammonia 
consumed. 
M. M. Gay Lussac and Thenard* are said to have procured 
from the fusible substance, by the application of a strong he at, 
two fifths of the quantity of ammonia that had disappeared in 
their first process, and a quantity of hydrogene and nitrogene 
in the proportions in which they exist in ammonia, equal to 
one fifth more. 
* No notice is taken of the apparatus used by M. M. Gay Lussac and The- 
nar d in the Moniteur ; but, from the tenour of the details, it see ns that they must 
have operated in glass vessels in the way heretofore adopted over mercury. 
