294 EXPERIMENTS AND OBSERVATIONS 
fected, by conducting the experiment in an apparatus some- 
what on the principle of the instrument invented by Dr Wot- 
LAsToN, which he named the Cryophorus. In a retort of the 
capacity of seven cubic inches, fitted with a stop-cock, and ex- 
hausted, sixty cubic inches of ammoniacal gas were combined 
with the requisite quantity of muriatic acid gas, each previous- 
ly carefully dried,—the former by exposure to potash, the lat- 
ter by-exposure to muriate of lime. . The stop-cock was then 
detached from the retort ; the excess of ammoniacal gas was 
removed by a caoutchouc bottle, and replaced by atmospheric 
air; the salt was pushed down from the neck ; and it was con- 
nected with another similar retort, the joining of the two be- 
ing secured by cement. This last retort was also fitted with a 
stop-cock adapted to a tubulature at its curvature,and heat be- 
ing applied to it, a little of the included air was allowed to 
escape. It was then placed in a mixture of muriate of lime and 
ice, while the other, containing the muriate of ammonia, was pla- 
ced in warm oil. The heat of this was raised to 420° ef Fahrenheit: 
moisture condensed at the upper.part of the neck, when the 
heat had.been raised to 220°, and continued for some time to 
increase. It then diminished, from the continued application 
of the heat, :carrying it forward. into the cold retort, and at the 
end of the.experiment a considerable part of the body of this 
was encrusted with.a thin film of ice. This result, therefore, 
coincides entirely with what had been before obtained *. 
Another 
* A foreign chemist, who has continued to support the old doctrine of the na- 
ture of muriatic acid, has observed, (Annals of Philosophy, vol. viii. p. 204.) that 
the water of the muriatic acid gas cannot be supposed to be obtained by the 
combination of the acid with ammonia, for no neutral ammoniacal salt, he adds, 
can be obtained free from water, and the water of the acid gas becomes the wa- 
ter 
