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 all ages that preceded it. And yet, applied science is only in the first early dawn of its power.

Berthelot was quite sure that physics and chemistry would soon solve the problem of aerial navigation, and he significantly remarked that when they do so "custom-houses will fall of themselves." That would be something like a revolution in the world's institutions, but it would be second to the discovery of artificial wheat and meat.

Although glycerine was discovered by Scheele in 1779, and its formula established by Pelouze in 1836, it was not until 1854 that its true composition was known. This was due to Berthelot, who proved that it is an alcoholic compound capable of interacting with three molecules of such acids as acetic and palmitic.

In 1860 Berthelot's book, Chimie Organique fondée sur la Synthèse, was published. It was the first of its kind, being based entirely on synthesis. His methods were simple and direct. By means of the electric spark, carbon and hydrogen united to form acetylene; or by the action of electricity on a mixture of hydrogen and carbon monoxide, the same gas is formed; also by the action of the spark on a mixture of hydrogen with carbon disulphide vapour or cyanogen. The conversion of acetylene into ethylene, and the synthesis of alcohol were also important reactions. Acetylene polymerizes, under the influence of the electric spark, into benzene, and