indkx. F\ 409 



Page. 



Gaps ; none in Bower mountain, 231 



11 of Sherman creek through Chestnut ridge, . . .... 232 



11 numerous through Chestnut ridge on account of thinness of iron SS. 



and ore SS. in Madison t., 247 



" of Susquehanna now at Liverpool, tine, 241 



" in Buffalo hills, Miller t., ... 270 

 " of Buffalo creek, through Bilman ridge, (VIII c 2,) in Saville t., pic- 

 turesque, . . 321 



" in mountains in IV, Toboyne t., 356 



Gap in the series of formations, Note to 38 



Garner's quarries of VI, Spring t., 161,337 



Garling, (W.,) 189 



Genesee formation— See VIII d. 



Gibson, Chief Justice, 157 



Geological structure, 31 ; history, 35 



Gibson's (F. ) old quarry in VI b, Spring t, 337 



" ochre bed, 101 



" gap through VIII c 2 ridge, Carroll t., 162 



Gibson's rock, end of Rock hill, Carroll t., . , 83,101,157,162 



" " road, crossed by fault, 85 



Girty's notch on the Susquehanna river, Buffalo t., 89,150,378,380 



" " fossil ore of VIII c 2, 100,382 



Girty, (Simon,) the outlaw ; his cave, 151 



Glen school-house, 2 m. N. of Bridgeport, 338 



" " exposure of 40' of VIII b 3, same fossils as Falling Spring, . . . 339 



Gradient of Susquehanna, 1'.82 per mile, 19 



" of Juniata river, about 2' per mile, 23 



Gravel 60' to 80' above level of McCabe's run, 369 



" flood plain 30' to 40' above Susquehanna river, 378 



Graveyard, old, in Miller t., 267 



Gray shales of V b, in Penn t., described, 55 



" " no gypsum known in Perry co., 55 



Great Horseshoe dyke, Penn t, 296 



» « " in Rye t., 200' (?) wide (500' crop,) 316 



Green sandstone, . 77,78 



" shales of V, bottom of red shale, .45 



" spots in red shale, 53 



" color of VIII c 1 flags, conspicuous in Saville t, 327 



" Park in Tyrone t., . . . . . 5 



u " road, VIII b 3 exposed 75', Spring t., 340 



" run drains past Oak Grove furnace to Sherman's cr. 3 m. W. of Gib- 

 son's rock, Spring t., 333 



" " valley, synclinal, 29 



Green valley, Tyrone t., 373 



Greenwood township described, 213 



Grier's Point (Keystone) Fenwick valley, 29 



" in Rye t., 4 



Grier, (S.,) . . 165,107 



Grier's (W.) sand from VII, near N. Bloomfield, 209 



Gypseous beds of V b wanting, 52 



Haldeman's island, Watts t., 377,384 



