THE DRIFTLESS REGION OF WISCONSIN 835 
of the gorge is only as about I to 100. It would, morever, be 
necessary to account for the removal of material to a point con- 
siderably below present river level, which could only have been 
possible during a period of greater elevation, of which the gorge 
gives no indication. 
c. There is excellent reason for believing that no torrents 
could have existed in these valleys capable of transporting the 
heavy bowlders found in the deposits. Of course I do not deny 
that torrents of sufficient power exist. I simply assert that in 
this as in all cases the question must be decided on the basis of 
local conditions. During the years that I have been familiar 
with the locality there have occurred several very heavy rains, 
and one of terrible severity, but never have I seen material 
transported reaching even the hundredth part of the weight of 
masses occurring in the deposits in question. 
Moreover, a degree of subsidence sufficient to have allowed 
these deposits by such agency would have brought the valleys 
into the condition of broad flats with gentle slopes in which 
powerful torrential action would have been out of the question. 
We have also in the stratified beds, deposits formed under the 
conditions assumed, and having the characteristics we should 
expect. 
Local glaciers.— That these, if we can suppose them to have 
existed, could have produced the specific effects above described, 
will not, I think, be questioned. I will, therefore, confine fur- 
ther remarks to facts having a negative bearing. Some of these 
have been anticipated in speaking of those favoring torrential 
agency. A further fact is that no undoubted case of glacial 
polishing or striation has yet been found, either on transported 
material or on the valley walls. The force of the objection is, 
however, practically destroyed by the fact that so far I have 
found only three exposures of rock so situated as to have fallen 
within the range of glacier action, while the transported mate- 
rial in sight, has been carried but a short distance and the 
greater share of that over beds of earlier deposit. 
A more serious objection might be based on the general 
