282 ACCOUNT OF THE ARCTIC REGIONS. 



Fresh-water ice of the sailors, is distinguished 

 by its black appearance when floating in small 

 pieces in the sea, and by its transparency when re- 

 moved into the air/ Large pieces may occasionally 

 be obtained, possessing a degree of purity and 

 transparency, equal to those of the most beautiful 

 crystal ; but generally, its transparency is inter- 

 rupted by numerous small globular or pear-shaped 

 air-bubbles : these frequently form continuous lines 

 intersecting the ice in a direction apparently per- 

 pendicular to its plane of formation. 



Fresh- water ice is fragile, but hard ; the edges 

 of a fractured part, are frequently so keen, as to 

 inflict a wound like glass. The most transparent 

 pieces are capable of concentrating the rays of the 

 sun, so as to produce a considerable intensity of 

 heat. With a lump of ice, of by no means regu- 

 lar convexity, I have frequently burnt wood, fired 

 gunpowder, melted lead, and lit the sailors' pipes, 

 to their great astonishment ; all of whom, who could 

 procure the needful articles, eagerly flocked around 

 me, for the satisfaction of smoking a pipe ignited 

 by such extraordinary means. Their astonishment 

 was increased, on observing, that the ice remained 

 firm and pellucid, while the solar rays emerging 

 from it were so hot, that the hand could not be kept 

 longer in the focus than for the space of a few se- 

 conds. In the formation of these lenses, I roughed 

 them out with a small axe, then scraped them with a 



