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112 C..A. White—Glacial Drift in Montana and Dakota. — 
Art. XVL.—@lacial Drift in Montana and Dakota; by 
CHARLES A. WHITE. 
4 [Published, in advance by permission of the Director of the U.S. Geol. Survey.] 
In this Journal for March, 1883, page 206, I announced the ~ 
- presence of true northern glacial drift in the region about the 
mouth of Yellowstone River. While prosecuting geological 
work in Northwestern Montana last summer, including a row- 
boat journey down the, Missouri River, my observations of that 
drift were extended much farther westward. These observa- 
tions were largely confined to the immediate valley of the 
Missouri River, but a part of them extended to the vicinity of 
the Bear Paw Mountains. They extended continuously from 
the Great Falls of the Missouri, to Bismarck, Dakota; and more 
or less of the drift material was seen at intervals all the way, 
a distance of more than a thousand miles. As a rule, the 
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