Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/40

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12 F³.
E. V. d’Invilliers, 1889.

The farming land narrows conspicuously along the south side of Shade mountain in Snyder county, although in this portion of the district, owing to superior facilities for marketing the product, the country occupied by the No. VIII rocks is more largely cleared and tilled and with encouraging results.

Rivers and Streams.

The Susquehanna river forms the eastern boundary line of the district and the county line of Union and Snyder from a point below the Montgomery bridge to McKee’s Half Falls at the mouth of Mahantango creek. Its air line length is about 33 miles, but measured by the meanderings of the stream this distance is increased to about 42 miles; 22 miles to a junction with the North branch at Sunbury, and 20 miles from there to Mahantango.

The river is everywhere quite shallow, and from one-half to one mile in width, flowing over a rocky channel of various formations, with a comparatively slight dip.

From the northern extremity of the district in Gregg township, of Union county, to Sunbury, the West Branch keeps a S. S. E. course with two prominent bends at White Deers Mills and Lewisburg. From Sunbury the course is S. S. W. with a western bend at Selinsgrove and an eastern bend at Port Trevorton. Numerous islands obstruct the channel throughout its course in the district, increasing the picturesque beauty of the river.

Reference to the table in Report N will at once indicate the very gentle fall of the river. Thus in the 24 miles between Montgomery and Sunbury (see table 129 Philadelphia and Erie railroad) the total fall is 490—444=46′, or scarcely 2′ per mile. From Sunbury to Mahantango creek (see table 110 Northern Central R. R.) the fall is 444—404=40′, or just about 2′ per mile. From that point to Harrisburg the fall is even less, or about 1.82′ per mile.′

The entire drainage of Union and Snyder counties is eastward, directly into the Susquehanna, the principal branch streams being as follows from north southwards:

1st, White Deer Hole creek, which with its tributaries