Page:Popular Science Monthly Volume 90.djvu/895

 Popular 'Science Mdnthlf)^

��87^

��in sufficient quantity to meet our demand entirely, though it will be if the present increase in production continues.

Aniline Dyes Valuable in Bacteriology

Aside from the common uses of aniline dyes may be noted the vast requirements of bacteriology. This science has made incredible progress since the staining of microscopic preparations with aniline dyes has enabled scientists to distinguish and recognize germs. Thus typhoid, cholera, tuberculosis, and other baffling diseases have been defined and studied.

The most familiar explosive in the minds of mortals today is T. X. T. (tri - nitro - toluene) — a coal tar prod- uct. It is an oil belonging to the benzol group, and obtained by the distillation of pri- man,^ oil. It is the result of com- bining nitric acid with ^ pure toluene. When being ^ poured into shells, T. N. T. looks like thick, syrupy chocolate.

Carbolic Acid Has Many Uses

Phenol (carbolic acid) is consumed in the United States at the annual rate of from eight to ten million pounds. The pro- duction of certain explosives depends on phenol. It is used in making picric acid

( Taniun dye) ( Tajinj^ and Acid Dye) RED 1 (RED t/tovrt Taamn Dye) ( Taimin Dye) RED

����Whole trainloads of wood to be cre- osoted are run into long cylinders and allowe[d t,o s.'oak for several days

A square yard of wood block pave- ment contains 45.36 pints of creosote oil

and also aniline colors.

The great value of phenol

was still further heightened

by the invention, b\' Dr. L. H.

Baekeland, of a peculiar resinous

substance which can be used in place

of hard rubber. It seems like a magician's

trick to combine two such strong-smelling

liquids as carbolic acid and formalin to

���HitroBeniol

��^^^^M I^^Kl^l \^-n^ry^ |Pht.3Acid| fe*ffi!5l lA»tl«c,nan

��Benzol

��Toluol

��^

��Xykd

��Nitro Waphlhalin

��Naphthalin

��Unidifapfathi

��Anthracim

��UGHTOIL

��JMEMOMOCJ

��HEAVY OIL I

��This chart will give some idea of the formation of various red dyes. It may be noted that niost ot these colors start from light oil; also that certain shades may be formed in two ways

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