26 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



By many of the early students the surface bowlders were thought to 

 be a distinct deposit from the sheet of drift which they cover, biit some of 

 the earliest writers found them to be a part of that sheet. Thus, Darius 

 and I. A. Lapliam noted, in 1832, the occurrence of bowlders in the blue 

 and yellow clays of the "diluvium" near Circleville, Ohio. They remarked 

 also that the rounding of the bowlders is independent of modern stream 

 action.-' 



The effect of the drift on the northern tributaries of the Ohio was early 

 recognized by Di-ake, who, in 1817, called attention to the fact that the 

 drift terraces are found on northern but not on southern tributaries, and 

 that the northern tributaries have been so filled by the drift that their 

 descent to the Ohio is much more rapid than that of southern tributaries. 

 Drake also discussed, quite clearly for so early a date, the extent of the 

 erratics in the Mississippi Basin, his discussion being based upon his own 

 observations, coupled with those of his friends, Nuttall, Goforth, and 

 Warren. The agent of transportation is thought by him to have been 

 icebergs.^ 



Among other early papers worthy of special mention is one by J. T. 

 Plummer, of Richmond, Ind., which contains a lucid description of striae 

 and drift in the vicinity of that city.^ Several papers by Whittlesey are 

 full of important data, among which may be mentioned Notes on the Drift 

 of Ohio and the West,* Fresh Water Glacial Drift of the Northwestern 

 States,' and Ice Movements in the St. Lawrence Valley." Alfred T. King 

 presented a brief but discriminating discussion of the Ancient Alluvium 

 of the Ohio and Tributaries in an early volume of the Philadelphia Academy 

 of Sciences.^ 0. N. Stoddai'd early called attention to a bowlder pave- 

 ment in Ohio and urged it as evidence of glacial action.^ 



E. B. Andrews discussed the relation of the river terraces of southern 

 Ohio to drift theories, and held that they were glacial dependencies, rather 



1 Am. Jour. Sci., 1st series, Vol. XXII, 1832, pp. 300-303. 



-Paper read before the American Philosophical Society in 1818; published in Trans. Am. Philos. 

 Soc, new series, Vol. II, 1825, pp. 124-139. 



'Am. Jour. Sci., 1st series, Vol. XLIV, 1843, pp. 281-315. 



*Idem, 2d series, Vol. V, 1843, pp. 205-217. 



5 Smithsonian Contrib., Vol. XV., 1867, 82 pages. 



«Proc. Am. Assoc. Adv. Sci., Vol. XV, 1867, pp. 43-54. 



'Proc. Phila. Acad. Sci., Vol. VII, 1856, pp. 4-8. 



«Am. Jour. Sci., 2d series, Vol. XXVIII., 1859, pp. 227-228. 



