23 



ftrtslj Ijj y a riff bare iho structure of the external Liver of llit buViUe- Tins p<.<r(iun we 

 wmt conceive to have be^o. nearer the prMiialiiijj superjacent rocks ilia ci 1 lie ee Mtral anil higher 

 DHSSj (wliidi wtt* probably denuded to I ho undent lit-fore il vrn* olcTstlod lo its present k-velj 

 md Hie greil Tariatioa* in SU structure and in^rcilieuEs may havr result exl from that 

 rircuniAlaocc under I ho influences previously adverted to (I). 



The leading fad relating lea tins structure of Lhrr rnrks is, I hat Mm principal vert teal or 

 appro* LumEdy verrie.il planes of division hnvu a general di recti on apprciLTrniLiiLCF to NE. 

 . , . SW. It if. ulso observable thai the touch of softer rock and tho majority of the (frooves 

 have the same direct iom. Puh If bin lies in the great plutonlc band or deration Wretch inn; 

 from A$mm Eo Bancs, and having , from Junkwyfon southwards, ■ south easterly direc- 

 tion* Tho divisional plane* are therefore nearly at right angles to the aiii of deration, 

 U thia a. general g-Qological phenomenon? It probably it, brejnsc in a locality so far rennor- 

 cd n* the south west of Englatuf. it ii repeated. Sir II. bis. la Ekciii mforjiui m (hat tho 

 divisional plane* of I he rjmuite and other rock* ip Cornwall and Devon are generally 

 [SNW. . . . SEE. The grand conclusion which fie draws a, I Fiat this direction approx- 

 imate* to (he present mn^oeEic meridian of ihe district, and may therefore, in il* origin t 

 be related 1o it. Pro-occupied wilh this vip-\t he has overlooked the fact thai this di roc lion 

 h ii L l- h . r 1 1 ! :i[\^1JBi to I he direction of the; principal granite massed of the? district (E, 24" IT 

 W* 24* {%} which f hqjE lining at Iktrimoor , ore continued to ihe Stilly Island*, Not 

 merely the south western division of £nffhmd y hut ihe general coo G^ru ration of eIje* Brtiiih 

 folandt j, scorns 1o br: due Eo Qics of clevalson hoTing- ihe sumo or an approximate range. 

 Thus the fjrcit body of Scotland and /r^JanoF may bo considered as one connected mass 

 ii [i raited an such aitzri. ProftRMr Phillips (1) mention* that the niolielinal air* of I he High- 

 land* and Lamm&mimrt in Scotland proloiifjcd to Donegal and Cavan in Ireland f and thoie 

 of the Cumbrian mountains , fA* /tto of Man, and North Wafot f aJL ratirjc NE, and SW. 

 It also appears from Profe-SFor Paiuzrs diagram ihewinfj I ho result of his examination of the 

 join U in the mountain Limestone diaJrict* of the north of Ettgtand, that Eht- f*fe*l majority 

 of the divisional phi nc* arc there in NNW. mad SSE, lines | -V) . X coincident range 

 hat been observed in the joints in other localities in England, and also in Franc* i more 

 pHTUruUrlf ' Says Sir U. u Ufjcuk a ui [jraiures and grange ht ■"' (3). 1 lliink it probable. 



f 1 1 If 1*'* rifir* fiijrnnrn.l in a «ii*m- que nt part of Ml i ■ |iipnr ar* rorjp-ct , wn muiL rrcn^nie* in granitic Aui 

 mi"" ■ piri<9^ i in Ihft ff ifuj I ilequ'nit<ifln *f Ibi'ir Irrnjrrrnliirfl to 1 in- Tniiii^ jiofnl , *hpfi tJin rsl»rn»l \tjvr * 

 kninj; juil rilrntteil itiftf inld Ijin mparjnerjiL rarLi br ra^Minjt Ifarm icEn rll iUlnUoffl , Wll irrnEfj in Ell 

 fiKllirr rjtftniob 1»t f i vil nlliiiLion, H.'i;ri< Llir rilrrcill lijpfP iKouIhI dfleii fa« TiriiMe. ind Pirtlht of Iht rkieink- 

 rml fnprcd-itnt* *f tbt &d]ie»nl fm!iti\ b^rtuie tint m nnl ■lUw^d for lb*ir kli«r«ufih n»Fi1iii-« wilft (bp gvivnil 

 Bfl<i- fo fa^l Ibli lijtir nml nfl«n h* mtralj m lircr «f Ihn idjufp-nt ro^k fuiril Jowji and imiti^Jiilrlr cryiUlliz- 

 *ii inln • gr*aiU, (S** npt», p. 33 h Pflil. > 

 (2J U Utr^i'i A*p*rl p. 157- 



(3J fnan"i# 0ji G*at»gf 7nA tsL p. 



(4) /rf- lit vol. p. 65, 



■; S i Arpnrf 7 . IT. i . 



