1899: Report of the commissioners of the state geological and topographical survey 1899/1900-1910/1912: Topographic and geologic survey of Pennsylvania 1912/1914: Biennial report of the Topographic and geologic survey of Pennsylvania
Work done in cooperation with the U.S. Geological Survey.
The 1st report covers 1899; the 2d covers 1899-1900, and has some statistics for 1901; and the 3d ... 1899-1906.
7 v. illus., plates (part fold.) maps (part double, part fold.) fold. plans, diagrs. (part fold.) 25 cm.