With which revelation of an attitude worthy
of Mark Tapley himself, this chapter may well conclude.

CHAPTER XX

EDISON PORTLAND CEMENT

NEW developments in recent years have been more striking than the
general adoption of cement for structural purposes of all kinds in
the United States; or than the increase in its manufacture here. As
a material for the construction of office buildings, factories, and
dwellings, it has lately enjoyed an extraordinary vogue; yet every
indication is confirmatory of the belief that such use has barely begun.
Various reasons may be cited, such as the growing scarcity of wood, once
the favorite building material in many parts of the country, and the
increasing dearness of brick and stone. The fact remains, indisputable,
and demonstrated flatly by the statistics of production. In 1902 the
American output of cement was placed at about 21,000,000 barrels,
valued at over $17,000,000. In 1907 the production is given as nearly
49,000,000 barrels. Here then is an industry that doubled in five years.
The average rate of industrial growth in the United States is 10 per
cent. a year, or doubling every ten years. It is a singular fact that
electricity also so far exceeds the normal rate as to double in value
and quantity of output and investment every five years. There is perhaps
more than ordinary coincidence in the association of Edison with two
such active departments of progress.

As a purely manufacturing business the general cement industry is one
of even remote antiquity, and if Edison had entered into it merely as
a commercial enterprise by following paths already so well trodden, the
fact would hardly have been worthy of even passing notice. It is not in
his nature, however, to follow a beaten track except in regard to the
recognition of basic principles; so that while the manufacture of Edison
Portland cement embraces the main essentials and familiar processes of
cement-making, such as crushing, drying, mixing, roasting, and grinding,
his versatility and originality, as exemplified in the conception and
introduction of some bold and revolutionary methods and devices, have
resulted in raising his plant from the position of an outsider to the
rank of the fifth largest producer in the United States, in the short
space of five years after starting to manufacture.

Long before his advent in cement production, Edison had held very
pronounced views on the value of that material as the one