_ Apparatus for Solidifying Carbonic Acid. 299 
ing H’a single revolution in the opposite direction, the shoulder 
of G is brought firmly against the bottom of E, so that no es- 
cape is permitted directly upward, but only in a lateral direction 
through the brass tube L, which connects the generator with the 
receiver C. A washer of sheet lead should be placed around the 
shoulder of G, in order to secure a perfect metallic contact be- 
tween it and the bottom of E. 
The receiver C is made of the best boiler iron, which was 
Strongly welded around a cylinder and a bottom also welded in. 
It is of the same height as the generator, which is about one foot, 
but only about two inches in diameter internally, and has a capa- 
city of about one pint. This form enables it to resist much 
greater pressure than if it was of a larger diameter ; and it is 
Tather an advantage than otherwise to have it of the same length 
as the generator. 
