THE OCEAN. 341 



seventh of the thickness of the whole mass. During the first expedition of Ross, he 

 found an iceberg in Baffin's Bay, at the distance of seven leagues from the land, which 

 was measured by a party under Lieutenant Parry. Considerable difficulty was expe- 

 rienced in the attempt to land, as, in rowing round the berg, they found it perpendicular 

 in every place but one. When they had ascended to the top, which was perfectly flat, 

 they discovered a white bear in quiet possession of the mass, who plunged into the sea 

 without hesitation, and effected his escape. The party found the iceberg to be 4169 

 yards long, 3869 yards broad, and 51 feet high, being aground in 61 fathoms. Its 

 appearance was like that of the back of the Isle of Wight, and the cliffs resembled those 

 of the chalk range to the west of Dover. The weight of this mass was calculated to 

 amount to 1,292,397,673 tons. An iceberg examined by Captain Graah, on the east 

 coast of Greenland, rose 120 feet out of the water, had a circumference of 4000 feet at 

 the base, and its solid contents were estimated to be upwards of nine hundred millions of 

 cubic feet. When viewed at a distance, nothing can be more interesting than the appear- 

 ance of a considerable number of these formations, exhibiting an infinite variety of shape, 

 and requiring no stretch of imagination to convert them into a series of floating towers, 

 castles, churches, obelisks, and pyramids, or a snowy range of Alpine heights. No pencil, 

 an observer has remarked, has ever given any thing like the true effect of an iceberg. 

 In a picture, they are huge, uncouth masses, stuck in the sea ; while their chief beauty 

 and grandeur their slow stately motion, the whirling of the snow about their summits, 

 and the fearful groaning and crackling of their parts the picture cannot give. The ice 

 of the bergs is compact and solid, of a fine green tint verging to blue ; and large pieces 

 may be frequently obtained, equal to the most beautiful crystal in purity and trans- 

 parency. It is stated by Scoresby, that with a portion of this ice, of by no means regular 

 convexity, used as a burning lens, he has frequently burnt wood, fired gunpowder, melted 

 lead, and lit the sailors' pipes, to their no small astonishment, the ice itself remaining in 

 the mean while perfectly firm and pellucid. 



The great distinction of icebergs from sheet ice, besides that of shape, is, that they are 

 fresh-water formations, have their origin upon the land, and are identical with the 

 glaciers of the Alps and Himalaya. They are formed by the congelation of the fresh 

 water that pours annually from mountains of snow under the action of the solar rays, and 

 have their principal birth-place on the eastern shores of Greenland, and along the 

 coasts of Spitzbergen. In treating of glaciers, the undoubted fact of their motion was 

 referred to, with the circumstances which give rise to it. In relation to those of the 

 Alps, an attempt has been recently made to ascertain the rate of the movement by Pro- 

 fessor Forbes, who arrived at the following results with reference to part of the Mer de 

 Glace, at Montlavert, near Chamouny : 



From June 29th to Sept. 28th - - - 132 feet 



Oct. 10th to Dec. 12th - -70 



Dec. 12th to Feb. 17th - - 76 



Feb. 17th to April 4th - - 66 



April 4th to June 8th 88 



432 



To this Professor Forbes adds for the time in which no 

 observation was taken 



483 



The annual movement of the glacier may therefore be estimated at nearly five hundred 

 feet. By a similar slow yet sure progress, those of the northern regions, formed along 

 the coasts, advance to the sea. where enormous blocks are broken off by the action of the 



z 3 



