Abbeville, implements in drift at, 258. 
Abby’s Ferry, limestone at, 124. 
Accumulation of gravel, how taken place, 512. 
Age, geological, of gravels, as deduced from animal remains 
and plants, 283. 
Akey, D. B., authority in regard to human remains under 
basalt, 266. 
Alabama Flat, 85. 
Aleutian Islands, fossils from, 39. 
Alleghany, on Kanaka Creek, mines near, 436. 
Alpha, near Jamestown, gravel at, 137, 409. 
Alta Hill, near Grass Valley, 182. 
Altaville, gravel at, 129. 
Altitudes, tables of, general, 527-552. 
table of, near Plug Ugly, 417. 
at summit of North San Juan Divide, 407. 
Alturas Mountain, 444, 453. 
Amador County, gravels and volcanic, distribution of, 303. 
implements in gravel, 275. 
American Hill, on North San Juan Divide, 388, 390. 
on Wolf Creek, 440. 
Analysis of fossil wood, 236. 
of hippopotamus tooth, 245. 
of rhinoceros jaw, 244. 
Animal remains, age of gravels, as determined from, 283. 
difficulty of obtaining, 240. 
not human, in gravels, 239-258. 
Antiquity of human race in California, 279, 288, 321. 
American River, main river and branches, distribution of lava 
and gravel on, 303. 
Pliocene times, 499. 
Middle Fork of, Pliocene drainage, 494. 
character of upper basin, 497. 
North Fork of, its Pliocene representative, 
489. 
South Fork of, its former position, 504. 
Andesite, near La Porte, 453. 
Andesitic lava, above basalt, on Mooretown Ridge, 468. 
Andreas, San, gravel at, 129. 
implements under volcanic at, 274. 
Angel’s Camp, bed-rock near, 123. 
Appalachian Range, occurrence of diamonds in, 363. 
auriferous deposits of, 374. 
TN EX. 
Aqueduct City, 87, 90. 
Arkansas Claim, 109, 117. 
Area of gold mining in Sierra Nevada, 301. 
Arnott & Co.’s Mine, 462. 
Ashburner, W., in regard to Bear River gravel, 372. 
Auburn, bed-rock near, 85. 
Auchenia Californica, 248. 
Auriferous gravels, diamonds usually found in, 362. 
Auriferous slate belt of Sierra Nevada described, 44. 
Auriferous slates, evidence in regard to geological age of, 
summed up, 41. 
Aurora, unreliable character of mines at, 312. 
Australia, gold region of, 354. 
gravels of, compared with those of California, 374, 
375. 
large nuggets found in, 359. 
Avery, B. P., his views of the origin of the high gravels, 71. 
Axis, a granitic, in most great mountain-chains, 353. 
Ayer’s Claim, near Michigan Bluff, 93, 117. 
Badger Hill, on North San Juan Divide, 394. 
near Spanish Ranch, 472, 473. 
Bald Eagle Mine, 177. 
Bald Mountain, near Angel’s, locality of the Calaveras skull, 
267, 269. 
Canada Hill, topography of country see 
from, 498, ; 
near Forest City, 434. 
near La Porte, 445. 
near Little Grass Valley, 467. 
divide between South and Middle Forks, in | Bald Mountain Company, 213, 434. 
Bald Mountain Extension Company, 439. 
Balsam Flat, near Chips’s, 435. 
Banner Mountain, 181. 
Bannerville Tunnel, 183. 
Barometric observations, near You Bet, how made, 165. 
Basalt, appearance of, closing the volcanic epoch, 242. 
near Davis Point, 467, 468. 
from Forest City, 433. 
from Portwine, 455. 
from Post’s Claim, 469. 
from Sugar Loaf, near Pine Grove, 453. 
Basaltic overflows, in gravel region, their character, 242. 
Basiu channel, 93, 110. 
