1892.] NATURAL SCIENCES OF PHILADELPHIA. 475 



Then ascending the river to Sunbury, we drove some miles east 

 toward Kliuegrove, by a route which took us over a typical variety 

 of high and low laud, then westward some miles back of Shickilimy, 

 then up both branches of the Susquehanna to Montoui''s Ridge, and 

 over the higher land intervening. The result was to convince us 

 that about 200 feet limits the deposits of pebbles which can be in any 

 way connected W'ith terraces of the present river, and that there 

 were absolutely no deposits that could reasonably indicate the pres- 

 ence of land ice over that region at any time. A boulder of gneiss 

 one foot in diameter is reported from the fourth terrace at North- 

 umberland, 175 feet above the river. (G 7, p. 336.) 



We then ascended the river to Bloomsburg, and drove westward 

 to join the line of Lewis's terminal moraine near Knob Mountain, a 

 mile or two north of Orangeville, in Columbia County. Here Ave 

 found extensive terrace deposits in the valley of Fishing Creek, 

 risinw something- more than 100 feet above it. We also found con- 

 siderable deposits of transported boulders on the hills north of 

 Lightstreet, extending in a practically continuous sheet from 

 the terminal moraine which Lewis had located on the farm of Wm. 

 Beck, two miles north of Orangeville. Without much question the 

 ice extended here on the hills west of the river almost as far south- 

 west as Bloomsburg, and covered to a height of from 300 to 400 

 feet above the river, the projection of Montour's Ridge which 

 extends northeastward from the city. (See G 7, p. 256.) 



A drive over the uplands on the east side of the river as far as 

 Mifflinville, showed that there was nothing which could be attribu- 

 ted to glacial action over that area until reaching a point about two 

 miles south of Mifflinville, where a few conglomerate boulders and 

 some scratched stones appeared about 500 feet above the river. It 

 is perhaps possible that these may have been derived from the 

 higher outcrops on Kescopec Mountain, two or three miles to the 

 east. But they now rest on the surface of Hamilton slate, and are 

 separated from the mountain by a valley of considerable depth, 

 eroded by a small creek. So scarce, however, are these remnants of 

 the ice age that they escaped the eagle eye of Professor I. C. White. 

 (G. 7. p. 278.) But in view of the abundant signs observed 

 by him, as Avell as by myself on the other side of the river, I 

 have little hesitation in bringing the border of the glacial field on 

 the south side of the river, down to the west boundary of Mifflin 

 township. Professor White is also probably right in opposition to 



