366 The American Geologist, December, isin 
seen. The following directions were noted in ditferent places at this 
locality: 
Well preserved striiH bearing N. 25 degrees E., a few other faint marks 
at an angle of about 45 degrees to these. 
Well preserved striae N. W. toS. E. and several bearing a few degr(>es 
more westerly. 
Near the church — strongest marks N. 20 degrees E., faint marks ex- 
actly N. W. and S. E. 
A few more were seen varying at small angles from the directions 
given above. 
Former observers* have noted glacial stri.ne at the followiiij^- 
points : 
Sec. 36, T. 35 N., R. 19 W., bearing S. 40 degrees E. 
Sec. 29, T..34 N., R. 18 W.. shallow flutings, bearing about S. 45 de- 
grees E. 
At Hinckleyj" the glacial striae bear S. and S. 5 degrees W. 
Very few places sliow striation of a persistent character, 
and readily escape observation. At nearly every place the 
bearing of the stride is extremely variable, the directions be- 
ing frequently at right angles to each other, with many inter- 
mediate degrees of variation. 
The igneous flows dip in general toward the S. W. and W. 
S. W. This, with the tendency toward columnar structure 
gave opportunity for extensive destruction of the original 
cliffs. At such points as developed particular concentration 
of glacial abrasive action, which would be the case in those val- 
leys lying between two ridges of eruptive rocks, or at a gap 
in an opposing ridge, the destructive influence should be 
strongly marked. This influence is especially noticeable at the 
old glacial channel in Sec. 6, T. 83 N., R. 18 W., and in the 
village of Tajdors Falls, at the Dalles. The rock exposures 
above the 800-foot contour, at the last named locality, bear 
evidence of ice abrasion as a factor in widening this gap be- 
tween opposite cliffs, while the lower benches exhibit sufficient 
evidence of water action to explain all the erosion at that point. 
On the sandstone and shales the effect of the glacial erosion 
was almost wholly confined to scooping out valleys between 
parallel igneous ridges, resulting in the removal of the com- 
paratively soft sandstone to a level from 10 to 300 feet lower 
than the adjacent crystalline outcrops. 
*Geol. of Wisconsin, vol. iii, 1883, p. .382. 
tWarren Upham, Geol. and Nat. Hist. Survey Minn.., Final Rep., vol. 
II, 1888, p. 642. 
