INDEX. 
191 
Tage. 
Salmon Falls, height of _ 28 
Salmon River, Assure springs near mouth 
of, occurrence and features of - 1 69 
warm fissure spring in canyon of, oc- 
currence of 169 
springs near mouth of 162-163 
Sand dunes, occurrence and features 
of.. 140-141 
Sandhill Mountains, partial burial of, by- 
drifting sand 140 
Sand Spring, features of 163 
source of 165 
Scenery in southern Idaho, attractive- 
ness of 19-21 
Scoria from Cinder Buttes, characteris- 
tics of 75 
Scrope, G. P., reference to publication by. 84 
Sedimentary beds, economic importance 
of..-. 58 
(Tertiary), possible eastward exten- 
sion of » 59 
Sheep raising, destruction attributable to 146 
Shell Mountain, basalt exposed at, char- 
acter of 55 
fresh- water shells collected at 56 
Shoshone, well drilled at, unsuccessful . . 177 
Shoshone artesian slope, features of 180-181 
Shoshone Falls, domes and ridges near.. 96 
features of 125 
height of 28 
plate showing 28 
rocks at, character of 43-44 
Silurian rocks east of Snake River, occur- 
rence of 46 
Slater Creek, well drilled on, unsuccessful 189 
Slope, artesian, section of 158 
run-off influenced by 147 
Snake River, area on each side of, char- 
acter of 16 
canyon of, character of 54 
course, character, and discharge of . - . 25-26 
gold along, occurrence of _ 32 
gravel flood plain of, character of 30 
lowering of bed of, results of 123-124 
North Fork of, features of 134 
rocks forming prominent mountains 
east of, character of 46 
Shoshone Falls, plate showing 28 
South Fork of, upgrading of 133-134 
Twin Falls of, plate showing 124 
water power available along. _ .' 28 
waters of, above American Falls, use 
of.. 159-160 
Snake River and tributaries, water sup- 
ply from 159 
Snake River Basin, early geological his- 
tory of 48-49 
Snake River Canyon, Blue Lake alcove, 
looking south into, plate show- 
ing _ _ 128 
breccia in walls of, characteristics of. 115 
domes and ridges on border of, occur- 
rence of 98 
featuresof .. ... 124,125,126 
lava exposed in, thickness of 60 
lava (columnar) in, plate showing 
block of 60 
Page. 
Snake River Canyon, lava balls in walls 
of, occurrence of 114 
lava sheets in, irregularities in thick- 
ness of H7 
Little Canyon, looking south into, 
plate showing _ 126 
north wall of, height of 53 
plate showing 52 
plate showing north wall of, near 
mouth of Little Canyon 64 
plate showing view of, below mouth 
of Rattlesnake Creek 24 
plate showing view of, near Hager- 
man 24 
plate showing water-worn mass of 
basalt in, near Hagerman 146 
rocks in, character of 43 
sand drifts in and near 140 
section of, below Glenns Ferry 55 
sections of, near mouth of Bruneau 
River ...53,54 
section of wall of, below mouth of Can- 
yon Creek 52,53 
south wall of, plate showing 54 
springs in, section showing mode of 
origin of 150 
springs of, extent of ... 162-163 
springs from northern wall of, fea- 
tures of 26,165 
The Thousand Springs of, plate show- 
ing 26 
walls of, features of 126 
source of water pouring from 28 
Snake River lava, area covered by 60 
features of 95-96 
lava caves in, occurrence of 99 
map showing approximate extent of, 
in southern Idaho 13 
occurrence, extent and character of. . 59-66 
relation of, to Columbia River lava. . . 50-61 
remnant of, on Kinghill Creek, plate 
showing 60 
plate showing pressure ridges in, near 
Big Butte 94 
plate showing pressure ridge in, near 
Market Lake Craters 94 
source of 63-66 
Snake River Valley, character of 55-56 
Snowfall in the region 18 
Soda Springs, source of heat of 153 
Soils, analyses of 136,137 
seolian, analyses and character of - . 136-139 
alkaline, indications of 141 
alluvial, deposition of . . . 135-136 
erosion of, prevention of _ . . 146 
recent occurrence of 145-146 
residual, occurrence of 141 
water-laid, occurrence of 140 
Soils of the region, character of 24-25 
kinds and features of 135 141 
summary of 141 
South Fork of Snake River, upgrading 
of - 133,134 
Springs, character and occurrence of, in 
Snake River Valley . . . 26-28, 162-171 
development of 156 
formation of canyons by 127-130 
