170 



HISTORY OF 



nature are Jocked up from us, we find the sea ever opeii to out 

 necessities, aud patient of the hand of industry. 



But it must not be supposed, because in our temperate climate 

 we never see the sea frozen, that it is in the same manner open 

 in every part of it. A very little acquaintance with the accounts 

 of mariners, must have informed us, that at the polar regions it 

 is embarrassed with mountains and moving sheets of ice, that 

 often render it impassable. These tremendous floats are of dif- 

 ferent magnitudes ; sometimes rising more than a thousand feet 

 above the surface of the water ;' sometimes diffused into plains 

 of above two hundred leagues in length ; and, in many parts, 

 sixty or eighty broad. They are usually divided by fissures ; 

 one piece following another so close, that a person may step 

 from one to the other. Sometimes mountains are seen rising 

 amidst these plains, and presenting the appearance of a variegat- 

 ed landscape, with hills and valleys, houses, churches, and towers. 

 These are appearances in which all naturalists are agreed ; but 

 the great contest is respecting their formation. Mr Buffon 

 asserts,^ that they are formed from fresh water alone, which con- 

 gealing at the mouths of great rivers, accumulate those huge 

 masses that disturb navigation. However, this great naturalist 

 seems not to have been aware, that there are two sorts of ice 

 floating in these seas ; the flat ice and the mountain ice .- the 

 one formed of sea-water only ; the other of fresh.^ 



The flat, or driving ice, is entirely composed of sea-water ; 

 which, upon dissolution, is found to be salt; and is readily dis- 

 tinguished from the mountain, or fresh water jce, by its white- 

 ness, and want of transparency. This ice is much more terrible 

 to mariners than that which rises up in lumps : a ship can avoid 

 the one, as it is seen at a distance ; but it often gets in among 

 the other, which, sometimes closing, crushes it to pieces. This, 

 which manifestly has a diff'erent origin from the fresh-water ice, 

 may perhaps have been produced in the Icy Sea, beneath the 

 pole; or along the coasts of Spitzbergen or Nova-Zembla. 



The mountain ice, as was said, is different in every respect, 

 being formed of fresh water, and appearing hard and transparent , 

 it is generally of a pale green colour, though some pieces are of 

 a beautiful sky-blue ; many large masses also appear gray, and 



1 Cnuitz's History of Grcenlnod, vol. i. p, 31. 

 •2 Kiillcm, vol. ii. p. 91. 3 Crantz. 



