368 Topographical Phenomena in Indiana. 
extended my observations and investigations of the subject, and 
confidently believe that I am offering something new in what fol- 
lows for the consideration of the scientist and philosopher. 
In the month of May, 1881, I was employed on a railroad sur- 
vey from Indianapolis, Indiana, to a point on the Ohio river. 
Nearly all this time was spent in preliminary lines in Brown 
county, about fifty miles south of Indianapolis, to find a practica | 
ble line across the several high ridges running east and west 
across this county. These ridges, according to Dr. John Collett, 
State geologist, headed off the glacial drift from this place. Cer — 
tain it is there is no glacial drift south of the first or most noti: 
ern ridge, though both east and west of these ridges the drift ex- 
tends nearly to the Ohio river, and beyond it on the east side of 
the State. These hills or ridges look like small mountains bit 
they are only hills, there being no upheavals. The strata can% — 
traced through all the ridges. These hills are composed almos 
entirely of Waverly sandstone, or knob-stone, as Indiana geolo- | 
gists call it. Valleys have been eroded over 400 feet deep, by i 
small west flowing streams. The stone dissolves easily on eS) 
sure to the weather, hence the great amount of erosion by the 
small streams, much greater than the same water-shed shows ® l 
any other part of the State. 
In this region the steep hills face the south, though the difer 
ence between opposite slopes is not half so great as 1M the 
regions to the north. Lg 
In the glacial drift region, especially on the high or ie $ 
where the stream valleys are shallow, the east-west E 
streams lay up close against the foot of the hills on pov ie 
side, and these hills are often as steep as a pr ecipice, while de 
north side (facing southward) they are often not over TE 
grees from a horizontal. h-facing pilisi 
north-facing hills, or on the steeper east and 
In Brown county, before mentioned, I could not 
difference in the lean of the trees on the hillsides. ; 
these east-west ridges is composed of the deco pillsides 
before mentioned, and is very thin, especially 08 me facing 
this region the streams wash against the north ener r 
ward) noticeably more than the south side (facing E — — 
