Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/921

 The midst of this deposit ; and from every new grave opened there numbers of these shells, and more especially the first and third named above, are thrown out. The length of the whole Long Sault Rapids, from Long Sault Island to two miles below Cornwall at St. Regis Island is over eighteen miles.

9. On the Physics of Arctic Ice, as Explanatory of the Glacial Remains in Scotland. By Robert Brown, of Campster, M.A., Ph.D., F.R.G.S., &c.

(Communicated by Professor Ramsay, LL.D., F.R.S., F.G.S.)

Contents.

Introduction.

I. Glacier- system of Greenland.

1. The Interior Ice-field. 2. The Defluents of the Interior Ice-field. 3. The Iceberg. 4. The Subglacial Stream. 5. The Moraines. 6. Life near the Ice-fjord.

II. Action of Sea-ice.

Conclusions regarding the Bottom of Davis Strait.

III. Rise and Fall of the Greenland Coast.

1. Rise. | 2. Fall.

IV. Application of the facts regarding Arctic Ice-action as explanatory of Glacial and other Ice-remains in Britain.

1. The sub- Azoic Boulder-clay. 2. The Fossiliferous Brick-clays. 3. Gravel, Kaimes, &c. 4. Boulders. 5. Life in the Old Waters. 6. Inferences from Facts given.

Conclusion.

In touching again on the subject of Arctic ice-action and Glacial remains in Britain, I am well aware that I am risking the stirring up of a hardly subsided degree of controversy most disquieting to the peace of mind of men unwilling to enter the lists of combatants. Of late years, however, the subject has received new light from the hypothesis, propounded first, I believe, by Agassiz 1, that Scotland and other portions of the north of Europe were at one time covered with an icy mantle, and that it is to this, and not to the agency of floating ice, that the glacial 2 markings and remains so abundantly scattered over our country are due. More recently still, this theory, at one time so violently opposed, has been brought into almost universal favour by the publication of the fact that Greenland is at this day exactly in the condition in which Agassiz, reasoning on observed facts, hypothetically described North Britain to have been. This new start has been chiefly due to the writings of Dr. Heinrich

1 Edin. New Phil. Journ. vol. xxxiii. p. 217 ; Proc. Geol. Soc. vol. iii. p. 327.

2 I use the word " Glacial" as expressing all relating to ice, on sea or land; while the word glacier is, of course, used in the ordinary acceptation of the term.