r " 



,1,^.1! 



i 



y 



II. 



tLU 



732 



IIKI'OUT — 1884. 



cnverod with a mantle of dt'compnsod rock, then the ice would not reouire to oxert 

 any vory extraordinary power in order lo scoop out any niimher ot lulu, basin,, 

 and to leave enormous -apparently wator-worn boulders scattored over iliufaci' 

 of the country as we now find them. 



' In llrazil these, what may bo called, "boidders of decomposition," with their 

 surroundiiiff decomposed matrix, were mistaiten by Apissiz for frhiciii! bnuld,!. 

 drift. Their true value, liowovor, havinj,' been .suliseijuently ])ointed out |,v 

 I'rofespor llarlt, I examined some of these supposed f^lacial drifts in Isilit, imd |'|„,;j 

 personal observation can endorse Pnifessor Ilartt's view of tiieir nature.' 



The letter above quoted seemed at that time — 1h70— to elose tlie disnissidii; 

 nor, ?o far aa 1 am aware, iuis the theory I then ad\anped in exphinniidu dt' tjie 

 orififin of these rock basins l)een since alludeil to by any one. 'i'lierefure 1 tliDi^'lit 

 it was not inappro])riate or without inter(!st,on tliis occasion, and survouiRiedaswc 

 are by a vast. re;j^ion f)f such lakes and lakelets, to ajrain refer to llio subject. 



I liavo now notliinj^ to add to tlie facts stated in my letter written eijrlit year- 

 ajro. I have, however, siiu-c* tlien had consideral)le opportunities for studyinir tlif 

 lakes of our great Laurentian region, as well as the action of wintei' ici' arDiiiul 

 our coasts, and I am more than ever convinctHl of the ina(le(|uaoy of ice, iwiwcvcr 

 tliick, to scoo]) out s(did hard rocks, <ir to ])ro(luce tlie plienomena of lalics ami 

 boulders whicli our preat northern glaciated regions now present, Wliili- it' tli- 

 explanation I iiave advanced is admitted, and as yet I have lieard no objection t» 

 it, all dilliculty seems to disappear. 



C. On Foiats nf Dit^siinllari'ti/ mid RrxoAxhJanrc hrltvcen Arniltivi ami Srotti4. 

 Glacial Bah. Bij K.\i,i'ii Kk'iiakdsux, F.R.S.E. 



Mr. liichardson said that, in his ' Acadian Geology,' I'rincipal Pawsmi iravf the 

 following as a typical section of the su])erlicial geology of Acadia — thai is, Nnvu 

 Scotia, New Mrunswick, and I'rince I'Mwanl Island -and as. in some respecl>, al<o 

 applicable to Canada and .Maine, viz. : At the bottom, ])(>aty deposits ; then iiiistni' 

 tilled ])oulder-clay : then stratified Leda-clay, indicating deep water; and, Iii>tly, 

 gravel and sand-beds, the Saxicava-sand indicating shallow water. ^Ir. l{icliai'I.Min 

 pointed out wherein such a section dilfered from and resembled the glacial beds j1 

 Scotland. lie said the latter showed no such orderly arrangement as the AcaiJiiin, 

 and could not, as a rule, be divided into deep and shallow waterbeds. 'I'lie iniiriiu' 

 shells in the Scottish beds are all mixed up togetlier, regardless, as a ride, ol' tli'' 

 province — whether Arct ic or British, or both — towhich they properly Ixdoiig; vi'^ranl- 

 iess of the depths whicli they usually tenant, and re;,'ardle33 of the deposit (whether 

 «;lay, gravel, or sand) in which they are now found fossil. 'J'hey are likewise met 

 with at all heiglits, from tlie level of tlu! sea to more than /iOO feet above it. No 

 system of dispersion of boulder-erratics from defmite centres in Scotland seeras a.' 

 yet ascertained. Tlie i»eaty deposits occurring in I'rincipal 1 )awson's section Wo«' 

 the boulder-clay or till, occur in Scotland aliove it. With regard to points of 

 resemblance, the facies of the shells in Acadia and Scotland is similar, being ol' tln' 

 Arctic and British-Arctic type. Again, both in Acadia and Scotland, all the .-helh 

 glacial beds occur above the unstratilied l)oulder-clay or till. Mi. Itichardxnieitiil 

 various Scottish sections to prove this, and remarked tiiat the belief in earht'raiul 

 later boulder-days is of long standing in Scotland. He concluded by piiinliiifroiit 

 that, in their cardinal ft^atures, the Acadian and Scottish glacial beds seemed to 

 coincide. In both Acadia and Scotland tliat great mass of unstratilied clay kiiowii 

 as till existed ; and, doubtless, the geoKigists of the New World were, like tlio-f 

 of the Old, puzzled to account for its origin with certainty and satisfaction. The 

 question was left unsolved b\ the meeting of the British Association in luliiihiu'irli 

 in 1850, although then discussed by Hugh Miller and Professor .lolin Flemin?. 

 The author hoped that during the present meeting some advance would be madi' 

 in solving this great problem, as well as in correlating and arranging the glacial 

 beds of Canada, Acadia, and Britain. 



