419 
and Spencer. He accounts for “The Narrows”, as this very constricted 
portion of the river valley is called, by asserting that this portion of the 
valley is new, having been formed since the Illinois glaciation. The old 
channel, he says, was up McCormicks Creek, through the Flatwoods basin, 
and back to the present channel by way of Raccoon Creek. Leverett 
says: “The stream (White River) is now occupying a pre-glacial valley 
for a few miles in southwest Morgan County, and is also in a pre-glacial 
valley throughout much of its course below Owen County. But in its 
passage across Owen County it is opening a new yalley. It has been sug- 
gested that this stream had a subterranean passage across the sink-hole 
region of Owen County, in which case no well-defined surface channel may 
have been opened prior to the glacial invasion.” (The Illinois Glacial Lobe 
pp. 104, Monograph XXXVIII, U. 8S. Geol. Sury.) 
Both Collet and Leverett have expressed their belief that White River 
in its present passage across the Mitchell limestone region is in a new 
valley. Collet says that the old channel was through MeCormicks Creek, 
Flatwoods basin and Raccoon Creek. Siebenthal, in regard to Collet’s 
idea, says: “The Pleistocene terraces of Bean Blossom Creek clearly 
prove the pre-glacial valley of that creek to have been practically as it is 
at present. It is impossible to imagine how it could be cut down to its 
present depth, while White River, into which it emptied, was running at a 
level 150 feet higher than now, as it is alleged to have done. Moreover 
the gorge of McCormicks Creek is clearly post-glacial. And further, it 
empties into White River at least a mile below the upper end of the 
“Narrows,” whose existence it was brought forward to explain.’ (Twen- 
ty-first Annual Report, Ind. Geol. Surv., 1896, pp. 302). Thus Seibenthal 
makes it clear that Collet was in error in regard to the ancient channel of 
White River in the Mitchell limestone region. 
Leverett asserts that White River in Owen County is post-glacial, and 
suggests that the pre-glacial drainage was a series of channels through 
the limestone region. The writer in his examination of the area found no 
evidence of an ancient channel on either side of the present river in the 
limestone region of Owen County; and there is little, if any, evidence of 
its passage through the region ever having been subterranean. 
The constriction of the river just above Spencer is undoubtedly 
remarkable, and not geologists alone have asked the why of it. Puzzling 
as the “Narrows” are, they have a rather simple explanation. The valley 
here is very narrow in comparison to the extremely wide portions above 
