The world needs a new source of energy, an unspillable source.

Checking the alignment of a turbine shaft at the top of the guide bearing in TVA’s hydroelectric plant, Watts Bar Dam, Tenn. Located 530 miles above the mouth of the Tennessee River, the dam has an authorized power installation of 90,000 kw., which can be

HYDROELECTRIC

Image taken on 1940-01-01 00:00:00 by The Library of Congress.