On the Expeditions to the North Vole. 281 



?00 leagues in circumference, and nearly 400 feet high. Per- 

 haps James's island, noted in several charts, was itself one of these 

 masses of ice. Captain Wafer frankly confesses that he mistook 

 these fixed masses of aliont 500 feet in height for real islands. 

 Even the floating ice is often covered with large stones, and trees 

 torn up hy the roots, which appearance produces the idea of land. 

 It is very uncertain whether \he Dutch discovered, to the east of 

 Spitzljergen, a tract of land, or onlv a mass of ice : in one of 

 their voyages to the north of Nova Zemhla, they found a bank 

 of blueish ice, covered with soil, on which birds had built their 

 nests. Ilalf a century ago, two islands of ice were seen to fijc 

 themselves in the bay of Disco : the Dutch whale-ships visited 

 and assigned them a name. The same circumstance took place 

 about Iceland. 



Mr. Scoresbv informs us, that the water of the sea of Spitz- 

 bergen contains only 5i ounces of salt in a gallon of 231 cubical 

 inches : its weight is to pure water as 1,0^60, and it freezes in 

 a cold vi two degrees by a thermometer centigrade. Thus it is 

 probable, that in the polar nights, that is to say, during our 

 winter, the arctic seas are covered with ice. The history of dif- 

 ferent voyages furnishes us with proof of this ; — but let us resume 

 the physical discussion. 



The masses of floating ice arising from the water of the sea, 

 and ivhich is distinguished by its porous contexture (owing to the 

 mixture of the volatile qualities of plants), sink 4-5ths of their 

 thickness into the salt water, the latter being in a freezing state. 

 The masses formed of fresh water have a greater density and 

 more transparency. Mr. Scoresby made bnrning-glasses from 

 pieces of it, and lighted the pipes of t.he astonished sailors. These 

 bodies sink 15-if)ths of their thickness below the surface. It ap- 

 pears certain, that the bays and straits of the polar seas (not ge- 

 nerally very deep) are often obstructed by these masses, resting 

 at the bottom. The floating ices present obstacles not less re- 

 doubtable. — The concussion of the masses produces a tremendom 

 noise, whith warns the navigator with what facility his vessel would 

 be dashed to pieces, if he were placed between two of these float- 

 ing islands. It is even asserted that the wood carried off by the 

 currents kindles by the violent collision caused by the motion of 

 ihe ice; and flame and smoke arise amidst the gloom of eternal 

 winter. Pieces of floating wood have been often found burnt at 

 the extremities. In winter the intense cold continually occasions 

 these mountains of ice to split asunder, and at each moment may 

 be heard the explosion of these masse s which separate in enormoun 

 chasms. In spring, the motions of the ice chiefly consist in the 

 upsetting of those masses, which lose their equilibrium, because 

 ;iiOinc parts dissolve more rapidly than others. In all seasons tlic 



broken 



