CARBONIC ACID

This important compound is ohtained when any form of carbon, such as the diamond or pure charcoal, is burned in oxygen gas. It consists t/t 6 carbon-|-16 oxygen=22 carbonic acid; or of Carbon 1 atom.. 6 - • 27 27 Oxygen 2 16 • - 7273 1 22 10000 100 cubical inches of carbonic acid gas weigh 47 3 grains. Under a pre ure of 36 atmospheres, at the temperature of 32°, it becomes liquid; and when the pre ure which retains it in the liquid state is removed, the rapidity oft hi evaporation, and the sudden and enormous expansion of the vapour, are such as to produce a degree of cold unde i which the acid solidifies, forming a white concrete substance po e ed of very extraordinary properties. Mr [s. 210]