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Show APPENDIX E. GEOLOGY AND PALJEOOTOLOGY, BY PROF. JAB. HALL. ALBAHY, t*< bruatyt 1852. CAPTAIH STAtfSBTTKY? DEAR Sli:- I have examined with care the specimen* of rook* and fossils which you submitted to my inspection. Pflnd them, ' With some few exceptions, to represent very clearly the products of four distinct geological periods, as follows:- The older are me-tamorpKic rocks of Silurian or devonian age, ofr perhaps both; the next in order/ and recognisable by - their fossil remains,', are of the carboniferous period; the third are of the cretaceous period; and the fourth are of the tertiary. > Besides these there are the produces of ancient volcanic action in the ba& alts and amygdaloids, with some specimens of obsidian. * After a careful examination o( the specimens, and a comparison with the notes and journal which you submitted to me, I have marked upon the map of your - route, and upon the map of the Salt Lak> region, the different colours indicating* the character, of the geology at the different points where the specimens were collected. I ain aware that the specimens with thd notes, together, would have Warranted me in colouring in a more- extended manner, but I have preferred to confine myself to the position and actual evidences furnished by specimens. By having the map in this condition nothing is hazarded, and every new fact obtained can be readily added to it, or it may be filled up to s6m6 extent from the indications furnished by the topographical'features. It will be the- more satisfactory mode to follow your route in the remarks I shall make in this connection. • The first specimens furnished are from the west side of the Missouri River, near and atxyve Fort Leavenworth. These are all from* limestone of the. carboniferous period, and apparently from the upper of the two great limestones of this period in the west. The most conspicuous fossils are Productu*, Terebratula, Ac. |