34 The Chattahoochee River south of Columbus, Ga. (v) facing 50 35 Map of the same area as in Fig. 34 facing 50 36 A river channel in the Great Plains: The Red River northeast of Wichita Falls, Tex. (v) 51 37 A glacial drift plain in southwestern Michigan (v) 52 38 Map of the same area as in Fig. 37 53 39 Schoolcraft, Mich. (v) 54 40 Map of the same area as in Fig. 39 55 41 Kettleholes in glacial till southwest of Schoolcraft, Mich. (v) 56 MOUNTAIN FEATURES 42 Mt. Shasta, California (o) 58 43 A glacial gorge on the northeastern face of Mt. Shasta (o) 59 44 Yosemite Valley, California (o) 60 45 Map showing the angle of vision of Fig. 44 61 46 Cinder Cone on the eastern edge of the northern Sierra Nevada, California (o) 62 47 Map showing the angle of vision of Fig. 46 63 48 The top of Cinder Cone (o) 64 49 Simi Hills northwest of Santa Monica, Cal. (v) 65 50 Part of Santa Monica Mountains north of Santa Monica, Cal. (v) 66 51 Map of the region between the center of Los Angeles and Santa Monica, Cal., showing the location of Fig. 50 67 52 A young mountain gorge in the San Joaquin Hills, a coastal range in Southern California (v) 68 53 Canyon in sedimentary rocks near the mouth of the Pecos River, Texas (v) 70 MAPPING AND CHARTING FROM THE AIR 54 View across the western end of Lake Erie (o) 73 55 Map showing the angle of vision of Fig. 54 73 56 Rochester, N. Y. (v) facing 74 57 Map of the same area as in Fig. 56 facing 74 58 Index map showing the location of the airplane photographs in this book taken on the Atlantic seaboard of the northeastern United States 75 59 Marshlands on Chesapeake Bay south of the mouth of the York River, Virginia (v) 76 60 Left shore of the York River northwest of Gloucester Point, Va. (v) 77 61 The northwestern tip of Sandy Hook, New Jersey (v) 78 62 Beach cusps under water near Beach Haven, N. J. (v) 80 63 First stage in the formation of an inlet through a barrier beach: near Beach Haven, N. J. (v) 81