SPITSBERGEN. — FOllMATION OF ICEBERGS. 107 



him, escaped unhurt ; but the mate, and two more of 

 the crew, were killed, and many others were wound- 

 ed*. 



Icebergs are probably formed of more solid ice 

 than glaciers; but in every other respect they are very 

 similar. The ice of which they consist is, indeed, 

 a little porous ; but considerable pieces are found of 

 perfect transparency. Being wholly produced from 

 rain or snow, the w\ater is necessarily potable. Ice- 

 bergs have also the same kind of origin as glaciers. 

 The time of their foundation, or first stratum being 

 frozen, is probably nearly coeval with the land on 

 which they are lodged. Their subsequent increase 

 seems to have been produced by the congelation of 

 the sleet of summer or autumn, and of the bed of 

 snow annually accumulated in winter, which, being 

 partly dissolved by the summer sun, becomes conso- 

 lidated ; and, on the decline of the summer heat, 

 frozen into a new stratum of transparent ice. Snow 

 subjected by a gentle heat to a thawdng process, 

 is first converted into large grains of ice, and these 

 are united, and afterwards consolidated, under par- 

 ticular circumstances, by the water which filters 

 through among them. If, when this imperfectly 

 congealed mass has got cooled down below the 

 freezing temperature by an interval of cold weather, 



* Letter of John Chambers to William Heley, dated Bell 

 Sound, l6th June I619 ;— Pnrchas* " Pilgrime?," \t>1. iii. 

 p. 73i. 



