406 F\ REPORT OF PBOGRE88. E. W. CLAYPOLE 



Page. 



Earth crust subsides, 37 



East Dunoannon trap dyke, 298,384 



Kgolfs mill in Kennedy valley, Tyrone t., 57 



" saw-mill, Tyrone t., good exposure of Bridgeport SS., 373 



11 ore of V, very fossiliferous ; cross Tyrone t., 50; 371 



Elevation and subsidence; see Emergence, 306 



Blliotsburg in Spring t., 5,14,338 



" valley, part of vale of Bloomfield, 331 



" red shale valley, V 6, between Limestone ridge and Mahony ridge, 335 



" outspread of VI limestone, 337 



El vans; see Trap dykes, 79 



Emergence; see Elevation, 63 



" or shallow water shown by Kingsmill SS., Ac, 76 



" in Rye t. temporary, (VI, VII, VIII 6,) 309 



" in Chemung age, shown by pebble bed, Wheatfield t, 393 



Enslow's mill, Sherman's cr., mouth of Houston run, Jackson t., . . . . 230 



" road section of V b (801',) 233 



Erosion of river beds, 20 



" of Central Pennsylvania, 21 



" of Horse valley, 25,000', . 38 



" by the Juniata river, 39 



" from Perry co. 5,000000,000000 cub. yds. of rock, 39 ; one 5,000th of 



a yard per year, ... 40 



" shown by white chert bowlders in Little Buffalo Creek valley, 30' to 



50' above the present water level, .... 200 



" of gap, one mile west of Little Juniata gap, in Mahony ridge, worthy 



of study, . . . . 200 



" of vales in middle member of VIII c 2, making zig-zag narrows, as 



at Montebello, . . 203 



" by the Juniata river, in Howe t, 223 



" see Brick clay, 1 m. W. of Juniata, 237 



" of Buffalo creek, at Bilman Ridge gap, VIII c 2, curious and beauti- 

 ful instance of folded structure affecting topography, 321 



" of Sherman's creek, Tyrone t, . . 367 



" of valley of McCabe's run, shown by gravel deposits 60' to 80' above 



bed of run, Tyrone t., , . 369 



" between ridges of iron SS. and ore SS., Tyrone t., 370,371 



" of Susquehanna river, in Watts t., 377 



Error of thickness assigned to Genessee formation, 71 



Excavation by rivers; (see erosion), 39 



Fairview, in Toboyne t., 5 



Falling Spring, Spring t., 162,338-9 



" " fed by two springs, (out of VII,) etc., 339 



" " temperature, 66° F., • 348 



" " Stromatopora bed (VI B) well exposed, 337 



Farming in Centre t., 173 



Fault of Perry po., described in Ch. IV, .35,81 



• throws 280C; »»510', 85; 86 



" dbei not reach Hlue mountain, 86 



" doubled in Half Falls mountain, 87 



" measured by formations W75 (6700'), 88 



