Owen, D. Dale (1846). ‘Geological Chart of the Ohio Valley to accompany Dr. Dale Owen’s Paper’ in ‘On the Geology of the Western States of North America’, extract from QJGSOwen, David Dale (1846). Geological Chart of the Ohio Valley to accompany Dr. Dale Owens Paper in On the Geology of the Western States of North America, extract from Quarterly Journal of the Geological Society, v. 2, n. 8, pp. 433 447. Hand coloured fold out map, 1: 450,000 approx. 22. 5 x 29cm. in very good condition. Some pages of text are uncut. In very good condition. The Western States are in the context of the extent of the USA in the 1840s.