Papers 69-72 on technology.

CONTRIBUTIONS FROM THE MUSEUM OF HISTORY AND TECHNOLOGIE.

Smithsonian, Washington, 1968.

large 8vo. cloth. viii,146 pp. many (col) ills. -69: J.H. White. James Millholland and early railroad engineering. -70: A.H. Frazier. William Gun Price and the Price current meters. -71: E.M. Harris. Sir William Congreeve and his compound-plate printing. -72: J.N. Hoffman. Anthracite in the Lehigh Valley of Pennsylvania, 1820-45.