u 



Did dip being to the KE- These strata ^ like dsTihiao* are frcrrticiillv crcsied by fissure* at 

 riflhl angles to Ilium, and i*juiu Limes by fiiiolHCf system in a different di reel ion. In mma 

 phceS, particularly in the higher regie nij the (jneis*, though perfectly laminar, is not divid- 

 ed 311 1 a regular Shed* by pa ml lei scam* but u crossrd by fissures in all directions. In n lower 

 zone ul* the /limtifatfu a ran|je of granite tract* of considerable rjtUul qrctiri. This i*me u 

 parallel fo l he direction of i]lc atis uf lire mountains ind I lie strike uf the gneiss. The must 

 eastern tract, at CAuMijNwmif, is soft like the tfrawun uF Corfiioait, and contains much felspar 

 ■Alj Utile mica, ILird biouks ure strewed ever it, A portion of the rust mass b exclusive!} 

 felspar s which f it would necm p is *[ ratified". Near /Mt'fl, CupL LlLnaEiT cli-^fjbri sfimr sphe- 

 roidal blccl* of grca-L siie, which are cifcl rating in ihe .nm? manner 05 tho*e of Pufe 

 One of these won GO fuel in diameter. Numerous veins, consisting almost wholly of quartz 



and feaipar, traverse the granite. s lu ■ 1 alio k. Thn next maw, procmliir f weslwnTd , 41 



at Almm'uii-t where granite and granite gneiss occur, rk fourth mas* i* foetid at which 

 precisely remrmhlctf those to the eastward. It ,jj?pL\ir.i to pj.H# in|u gnei** 01) if* border*. On 

 it line jo Che westward *a rock oscillating between grauile and gnicts*" is found. Near 

 D&vtwvl the rock dirnriopmcnt in so interesting; in iiteJT and bears to much on the- fluhjerU 

 dUeusscd in this paipcr that ! shall, cite Captain Hamuli! descriptions tin a gcologknl &ense 

 the rock may be called a gneiss, but it exhibit* email patches (forming icguUr transitions 

 aroong*t thenm-lvcs) of the most regular mieaceoui schist [earthy type), arid, again, nf the 

 moat lepn'limatc (j ran tie faro wan), These three rocks t so different in com position j in mioera- 

 lo^juul cNiraelcr, and lei supposed rjuoluftLcai origin, mat be here u by erred in I lie ruin pas* 

 of a few yard a ail naturally (mutually*) inlcrehanfjeahle , while nothing' like a veinous ap- 

 pearance tan be atlrih uled to any of them". On the same lone wilh the preeeedin^ inui^c*., 

 but at a great dinlanee lo ihe westward , the Choor Pcakj wliieh rina to the height of 

 12000 feet t h comjMsed of j»ranite* 



The icIQc of is 24 rnilea id bm-odLh and include* Jill ihe higher ^ummili uf the 



Ilinmlotffii. Tiic gneiss woa seen at altitudes oV from SyQOO l« 4S,7(J9 feet* To I he south- 

 Wiird sueccedii a zuiie of ahuut the tamu hrundlli furuicil prii^ipulK el mlcaceoufi f fhlorilic , 

 tnlcopc nnd hornblendie §ch]ils> but includip^ limestone and ihe rjrpnitir tracts formerly 

 mentioned. These types vary exceedingly m themselves * and in their tramitiont into each 

 other. Thift icUwlOfie tract i* iacccedril hy n b*od of tunidikmii whieli is referred to ihe Ne* 

 Red. The general dtp of ail Ihe rocks Trom Ihe sendMone to the ^nciiis u from 2f'J* to SO 1 

 to the NE, or iQM-tffdtt the rjreat eetklral plutcau of Ari&< The lowest system Lr 1 hf refer t 

 the new red sandstone ; and tlie highest the gneiss. Caplnin Iduit seems to consider that 

 \hh faLTt or rjativei ihr idea thai the planes of apparent atralifieatiou ore really what they seem f 

 ocd he ii obviously rather disposed 1o refer them to n similar ocEioii to that which produced the 

 LiAjuren IraU^ertC la I hem. it if genrcely pufiKibtc to conceive that a continuous man of 

 strata, about CO miles in horizontal breadth at iheir present inclination j which would give 

 an. original vertical depth of ahnut sirtecn mil€i f should have been raised on ill edge and 

 made to move through an arc af toO* to ICO* until it rested in its prudtuE [jr^iUuli, with 

 the gneiss , originally 10 miles below the sandstone, now bi many raile* abnTt it Such 

 diiplaccmcut does so doubt wmctirn^ eecur on a gre$t scale. Thus in the Alps, and . at 



