J. Milne — Ice and Ice-work in Newfoundland. 407 



formed by the freezing of the "balacada" so firmly to the ground 

 at low water, that at the rising of the tide it remains beneath the 

 surface of the water. The consequence of these transportive move- 

 ments is that much material, both boulders and pebbles are carried 

 out to sea, and then deposited in a manner similar to that which 

 has so often been explained in the case of icebergs. Another con- 

 sequence is that similar materials are carried from point to point 

 along the coast, and on the disappearance of the ice are left as 

 monuments of its former existence. In places boulders may be 

 seen lining the shores in long lines, like tiers of barrels on a wharf, 

 as at Change Island. Boulders of this sort are referred to, and a 

 sketch of them is given, in Ly ell's Principles of Geology, vol. i. 

 p. 381. I have here spoken irrespective of the immense quantities 

 of boulders that are annually brought down attached to the "ground- 

 ice" of rivers. 



Movements of Coast-Ice. — On the first calm day the ice out at sea 

 along the edge of the pack commences to break up, and small lakes 

 and pools are formed between the pans. This appears to be due to 

 the tide. In a calm five square miles of ice will rapidly open out 

 and spread over 20 miles, during v^hich it is greatly smashed about 

 and tumbled. Oapt. A. Jackman, to whom I am indebted for many 

 facts regarding the action and formation of coast-ice, informed me 

 that on one occasion he knew of two vessels closely wedged in the 

 ice, which were separated 20 miles apart in one night during a 

 calm. A wind from seawards only jams it the tighter on the land, 

 whilst one from the shore sends it off in a body until there is suffi- 

 cient water between it and the land, where a sea can form, upon 

 which the ice is speedily dispersed. In calm v^eather the pack 

 travels with the current, but at other times it follows the direction 

 of the wind. Icebergs, on the contrary, although afiected by the 

 wind, have a more definite direction in their line of travel dependent 

 on currents. The consequence of this would appear to be that the 

 line of distribution of material derived from pack-ice is not so 

 definite in its direction as that of icebergs. In both cases the pro- 

 portion of the mass exposed above water to that which is submerged 

 is equal. The explanation therefore appears to lie mainly in the 

 fact that the pack only rests on the upper surface of the water, 

 which is affected by the wind, whereas the iceberg, descending to 

 greater depths, will move in a steady current unaffected by any such 

 surface disturbances. The ratio of the surface exposed above water 

 to that beneath it in the pan of ice, to that in the berg, must often- 

 times also be influential in the explanation of this phenomenon. 

 Should a berg be entangled in a pack, and the tide be contrary to 

 the wind, the berg may hold its own against both the wind and 

 pack, and, so to speak, will force for itself a passage. Capt. A. 

 Jackman has, whilst frozen in the pack, travelled at the rate of from 

 two to three knots per hour past bergs, but whether these were 

 aground or not was not definitely stated. 



Condiisious regarding Coast-Ice. — As before remarked, it would 

 appear that coast-ice might at least be considered as an agent in the 



