TKANSACTIOXS Ol' TUE SliCTlONS. . 87 



work of yestei'da}'. Is is difficult to conceive how ordinaiy atniospliei-ic agencies, 

 and even the tread of sheep and cattle, should not have broken such an arrangement 

 of loose material. But there are exc<iptionably f;\vourable circunistauces for the 

 preservation of these beds, from absence of considerable streams and the protec- 

 tion of surrounding- rocks. There is little or no evidence of glaciation anywhere 

 around ; and although it is certain that the sea which stood at those beaches so 

 recently was a sea subject to glacial conditions, it is equally certain either that it 

 continued to work there after those conditions had passed away, or, what is more 

 probable, that that particular line of coast v/as protected from the drift of surroinid- 

 ing ice-floes. 



If, now, vre compare the evidence of recent action in these sea-beaches with the 

 similar evidence connected with the position of erratics at far higher levels, Avhicli 

 can only have been placed there by floating ice, I cannot help coming to the con- 

 clusion that the submergence and reelevation of the land to the extent of more 

 than 2000 I'eet above the level of the present ocean has been one of the very latest 

 changes in the history of this portion of the globe ; and, moreover, that the reeleva- 

 tion has been comparatively rapid, probably by lifts or hitclies of considerable 

 extent, and that there vvere few, if any, pauses or rests comparable in duration with 

 those recorded in the Jm-a beaches and in the cutting of the existing coasts. 



Finally, let me repeat that whether this conclusion is correct or not (and I 

 am well aware of the many difficulties which siuTound it), the general fact of sub- 

 mergence and reelevation is, perhaps, as certain as any conclusion of geological 

 science, and that the consequences of it in accounting for the distribution of gravtds 

 and the most recent changes of denudation hare never as yet been worked out with 

 any thing approaching- to consistency or completeness. 



On tJie Suh-Wealden Exploration. D)j Major Beatthoxt, M.P. 



On the Granite of Strath-Erricl; Lough Ness. Bi/ James Bryce, LL.D. 



The author described a granite tract a little distance from the shores of Loch 

 Ness, and near the Fall of Foyers. This fall took place originally over a cliff of Old 

 Red Sandstone, and this stone being of a soft character gradually wore away until 

 it formed a magnificent basin almost inaccessible at the bottom, and the action of 

 the water had also worn the rock back to the slate which came between it and the 

 granite. His .attention had been called to the Loch-Ness granite tract by hearing 

 that gold had been fomid in the lower valley of the Nairn, which passes through 

 this granite district, and he supposed it probable that the gold might have its 

 source in this granite tract in the same way as he had found the granite of Suther- 

 la.ud to be the true source of gold. After describing the limits of the gi-anite 

 tract, he pointed out a most remarkable circumstance connected v.-ith its history, 

 which was illustrated by a section in a glen above Innerfaricaig. Here this triple 

 granite rises from the valley in a direction sloping eastward, at first leaning against 

 the Old Red Sandstone, and ultimately, further east, regularly overlying it, the 

 nielamorphism being very remarkable throug-h about a foot of depth, and portions 

 of gi-anite being embedded in the Old Red. On the east side of the hill the Old Red 

 Sandstone was regidarly overlapped by gi-anite, the strata of the Old Red dipping 

 imder it at an angle of 32 degrees. The well-known vitrified fort on the top of 

 the hill contains both rocks highly vitrified. To the west of this another hill rises 

 composed at the base of OldRed, audits upper part consisting of conglomerate granite. 

 He called the attention of the Section specially to this conglomerate granite, and to 

 the evidence which the whole district afforded that tlie granite here was truly 

 iiTuptive, and not of that hydrothermal origin to which the gi-anites furtlicr east 

 have been ascribed. The only conglomerate granite similar to this with which he 

 was acquainted was one that he had visited some years ago at Forkhill, county 

 Armagh ; and he called attention, especially of Professor Hull, to the connexions 

 of these beds to the probable origin of a great irruption of granrto. 



