F>G. 10. PART OF PAWPAW QUADRANGLE. MD.-W.VA. SCALE, 1:02.500; CONTOUR INTERVAL. 20 FEET
How individual our rivers become when we see them at close range, as we may on these admirable maps. Look at the Potomac here, where its right bank makes the dovetailed boundary between western Maryland and West Virginia. How gracefully its incised course swings in small and large curves beneath the hilly uplands 1 Observe the devices by which two railroads, and a canal also, strive to avoid the
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FIG. 11. PART OF LOCKPORT QUADRANGLE. KY.	SCALE,	1:62.500;	CONTOUR	INTERVAL.	20 FEET
devious course of the valley bottom, and save distance by cutting across the spurs, even at the expense of tunneling, and note the four locks by which the canal descends from its tunnel to the valley floor. How different from the smooth and well-enclosed curves of the Potomac are the curiously angular turns of the Kentucky river, Fig. 11, through its open amphitheaters! A fine prospect must be opened from the road on the edge of the curved 200-foot bluff that overlooks Craddock bottom; and another three miles farther south, from the ridge beneath which the river sweeps around Lecompte bottom, although without the map the view would not be suspected by a traveler on the road that follows the hollow on the eastj.and a similar prospect would reward the steep slanting ascent of the road that climbs the amphitheater wall on the west of Polsgrove bottom. Good lessons cn local physical geography might be based on this map: What is thcorigin of these semicircular “ bottoms ”? Why does the river sometimes follow the base of the amphitheater walls and sometimes avoid them? Why does it sometimes swing in large, smooth curves, and sometimes make sudden, rectangular bends?
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