ule Rubber," _Commerce Reports_, 1918, and _India Rubber World_,
1919. "Historical Sketch of Chemistry of Rubber" by S.C. Bradford in
_Science Progress_, v. II, p. 1.

CHAPTER IX

"The Cane Sugar Industry" (Bulletin No. 53, Miscellaneous Series,
Department of Commerce, 50 cents) gives agricultural and manufacturing
costs in Hawaii, Porto Rico, Louisiana and Cuba.

"Sugar and Its Value as Food," by Mary Hinman Abel. (Farmer's Bulletin
No. 535, Department of Agriculture, free.)

"Production of Sugar in the United States and Foreign Countries," by
Perry Elliott. (Department of Agriculture, 10 cents.)

"Conditions in the Sugar Market January to October, 1917," a pamphlet
published by the American Sugar Refining Company, 117 Wall Street, New
York, gives an admirable survey of the present situation as seen by the
refiners.

"Cuban Cane Sugar," by Robert Wiles, 1916 (Indianapolis: Bobbs-Merrill
Co., 75 cents), an attractive little book in simple language.

"The World's Cane Sugar Industry, Past and Present," by H.C.P. Geering.

"The Story of Sugar," by Prof. G.T. Surface of Yale (Appleton, 1910). A
very interesting and reliable book.

The "Digestibility of Glucose" is discussed in _Journal of Industrial
and Engineering Chemistry_, August, 1917. "Utilization of Beet Molasses"
in _Metallurgical and Chemical Engineering_, April 5, 1917.

CHAPTER X

"Maize," by Edward Alber (Bulletin of the Pan-American Union, January,
1915).

"Glucose," by Geo. W. Rolfe _(Scientific American Supplement_, May 15 or
November 6, 1915, and in Boger's "Industrial Chemistry").

On making ethyl alcohol from wood, see Bulletin No. 110, Special Agents'
Series, Department of Commerce (10 cents), and an article by F.W.
Kressmann in _Metallurgical and Chemical Engineering_, July 15, 1916. On
the manufacture and uses of industrial alcohol the Department of
Agriculture has issued for free distribution Farmer's Bulletin 269 and
424, and Department Bulletin 182.

On the "Utilization of Corn Cobs," see _Journal of Industrial and
Engineering Chemistry_, Nov., 1918. For John Winthrop's experiment, see
the same _Journal_, Jan., 1919.

CHAPTER XI

President Scherer's "Cotton as a World Power" (Stokes, 1916) is a
fascinating volume that combines the history, science and politics of
the plant and does not ignore the poetry and legend.

In the Yearbook of the Department of Agriculture for 1916 will be found
an interesting article by H.S. Bail