Note 15 — III A CENTURY OF GEOLOGY.—STEPS OF PROGRESS IN THE INTERPRETATION OF LAND FORMS
Reading edition
Hildreth, S. P., Observations, etc., valley of the Ohio, this Journal, 29, 1–148, 1836.
Reading edition
Hildreth, S. P., Observations, etc., valley of the Ohio, this Journal, 29, 1–148, 1836.