422 
of the ice-sheet itself, rather than to the exact drift line. In interpreting 
the Flatwoods phenomena the position of the advance of the ice-sheet itself 
is of fundamental importance. This line of advancement, as given below, 
was determined not only by the presence of erratic boulders and rocks, 
but by stratified outwash material as well. Of the two phenomena, per- 
haps the latter is the more important. 
A close examination of the hills or rather ridge extending eastward 
along the northern part of section 15, T. 9 N., R 3 W., thence northeast 
through section 11 and into section 1, shows that the ice-sheet never 
crossed beyond. Evidence is plentiful in showing that the ice rested 
against this ridge and remained close to it for some time. The west side 
of the small adjunct is an outwash plain, which in the headwaters of 
McBrides Creek shows the coarse layers of stratified gravel alternating with 
both coarse and fine sand. About a mile west of the Stogsdill Pond is the 
remnants of an old moraine, showing the last stand made by the ice front. 
The coarse sand found jin the ridge, dividing Flatwoods proper from the 
adjunct, is partly outwash material and partly the result of the ice-front 
itself in pushing material against the ridges, which the water later 
worked over. Undoubtedly a tongue of the ice-front pushed up to the very 
upper tributaries of the old stream, the lower part of which is now repre- 
sented by McBrides Creek, but that it never crossed the ridge between the 
old stream and Raccoon Creek to the east is certain. 
To the north the ice came up the White River slope and pushed up the 
old stream, draining the region now occupied by Flatwoods proper. It 
may have come up this old stream as far east as the Owen-Monroe County 
line, and even some distance farther, but for the most time it must have 
remained near the western border of the present Flatwoods. Alliston’s 
3ranch has been eating its way into an old outwash plain since the with- 
drawal of the ice from the region. It has erased the moraines, if any 
were formed, and has taken considerable of the head of the outwash plain. 
It is this outwash material, covered with later silt, that makes the slope 
of the western part of Flatwoods toward the centre of the region. It is 
evident from this that the ice-front for the most part did not extend 
beyond the headwaters of Alliston’s Branch, in sections 26 and 35, T. 10 
IN; fiver Wis 
No outwash material or erratic boulders were found in the extension 
of the Flatwoods basin into section 24, or on Chambers Hill, but erratic 
boulders were found in the northern part of section 23 on the White River 
