3° 



BULLETIN OF THE LABORATORIES 



Following along this valley, with its drift surface much cut up into 

 hills and valleys (yet when on top of the hills this surface appears quite 

 even) we reach a point H, near a large iron bridge across Brush creek, on 

 the pike from Sinking Springs to Carmel. Here is observed a side 

 valley entering from the northwest. Crossing the bridge and pro- 

 ceeding along the pike to a high hill of till at I, 191 feet above Paint 

 creek, 85 feet above the water in Brush creek at the bridge, the land- 

 marks at F are visible, and then is understood the reason why this val- 

 ley when viewed from F, appeared to be closed at its southeastern end. 



As we pass down the valley of Brush creek, it is noticed that 

 while the creek is running in a large valley in the drift-filling it is 

 nevertheless flowing with a very sluggish current. The high sand- 

 stone and slate hills are closer together and the rock valley is much 

 narrowed. One looks in vain for a gap in the hills which will indi- 

 cate the position of the exit of the creek. The only apparent open- 

 ing is in the direction from which we have come. 



We proceed to K along the bed of the creek which now* con- 

 tains no water, except in the deep holes and is a muddy and sandy 

 channel. Here is a small stream entering from the western continua- 

 tion of the old valley. Here also are found evidences of a buried 

 rock ravine which occupies a position more central to the main part 

 of the old valley. This old ravine is filled with till and its walls 

 but thinly covered. Its position is shown by a meander of the chan- 

 nel of Brush creek and also by a side ravine of recent erosion, which 

 crosses it. The small tributary to Brush creek is fed by a number of 

 springs and flows along the contact line of the drift and rock, along 

 the southern side of the old valley, its former ravine near the center 

 of the valley being filled with the drift. 



Standing at the mouth of this small stream, not 500 yards from 

 the place where the channel of Brush creek is transformed into a 

 narrow and deep gorge, one unfamiliar with the facts would find no 

 marks to indicate the location of the exit of Brush creek from this 

 apparent basin, so skillfully has nature concealed the facts by topo- 

 graphical features, and a luxuriant growth of underbrush along the 

 stream, gradually merging into the forest of the mountains sides. 



Shults' mountain, L, presents the most favorable opportunity for 

 a comprehensive view. From its summit, 440 feet above the waters 



♦August, 1895 ; an extremely dry season. 



