ON THE ACTION" OF COAST-ICE ON AN OSCILLATING AREA. 929 



49. On the Action of Coast-Ice on an Oscillating Area. By Prof. 

 John Milne, E.G.S., of the Imperial College of Engineering, 

 Tokio, Japan. (Read June 20, 1877.) 



[Abridged.] 



[In this paper the author commenced by discussing those theories 

 which have been proposed to account for glacial markings by the 

 assumption of a polar ice-cap. He argued that even if such vast 

 sheets of ice as are accepted by many geologists could have produced 

 the grooves and other markings, and the drift deposits ascribed to 

 their agency, the action of the sea during subsequent submergence 

 and upheaval of the regions where these phenomena are displayed 

 would certainly have effaced all such traces of ice -action. Other 

 objections might also be raised to the hypothesis of great ice-sbeets ; 

 and he thought it desirable to consider fully " whether other agents 

 may not have shared the work with which they have been credited." 

 He proceeds as follows : — J 



Excepting glacier-action, which will generally have taken place 

 in elevated regions, I think it can be shown that the modelling and 

 scratching has in many instances been produced by an agent the 

 existence of which is certain, and which acted under conditions 

 favourable to the preservation of its work. Such an agent is coast 

 or floe-ice acting on a rising area. 



Examples of the work done, and being done, by such an agent 

 under the stated conditions I shall take from Newfoundland, La- 

 brador, and Einland. Every year the shores of these countries are 

 surrounded by a fringe of ice. During the process of freezing and 

 at other times, by various causes, such as tides, currents, wind, the 

 driving in of pack-ice from the sea, this is forced up and down upon 

 the shore on which it rests. By actions such as these, which 

 extend sometimes 100 yards back above high water, the shore line 

 is scratched, scoured, and rounded. Boulders and angular stones 

 travel along the coast, and are often deposited in banks and lines far 

 removed from the cliffs or mountain masses from which they were 

 originally detached. These actions are perhaps best seen upon the 

 small islands which form archipelagos along the shores of all those 

 countries to which I have referred. 



Lying well out from the east coast of Newfoundland there is an 

 island called Eunk Island, which, through the action of the floe-ico 

 by which it is annually invaded, has, I believe, received not only the 

 ordinary marks due to the moulding of ice, but also its contour as a 

 whole. It is about half a mile in length, very low and flat, and is 

 situated right in the stream of arctic ice coming south from Baffin's 

 Bay and Labrador. The northern end of this island, which has 

 every year to face the pressure of the vast fields of ice which are 

 borne down upon it, is visibly worn down and covered with erratic 

 boulders, whilst the opposite extremity is a low but abrupt cliff. 



