POLAR-ICE. FORMATION OF F1EI,DS. 245 



probably be added by the following process. The 

 frost, which almost constantly prevails during nine 

 months of the year, relaxes towards the end of June or 

 beginning of July, whereby the covering of snow an- 

 nually deposited to the depth of two or three feet 

 on the ice*, dissolves. Now, as this field is suppos- 

 ed to arise amidst the older and heavier ice, it may 

 readily occupy the whole interval, and be cement- 

 ed to the old ice on every side, in such a manner as 

 to prevent the melted snow from making its escape. 

 Or, whatever be the means of its retention on the 

 surface of the young field, whether by the adjunc- 

 tion of higher ice, the elevation of its border by the 

 pressure of the surrounding ice, or the irregularity 

 of its own surface, several inches of ice must be ad- 

 ded to its thickness on the returning winter, by the 

 conversion of the snow-water into solid ice. This 

 process repeated for many successive years, or even 

 ages, together with the enlargement of its under- 

 side from the ocean, miglit be deemed sufficient to 

 produce the most stupendous bodies of ice that have 

 yet been discovered ; at the same time, that the ice 

 thus formed would doubtless correspond, in pu- 

 rity and transparency, with that of fields in gene- 

 ral. 



• That snow is deposited on the ice in high northern lati- 

 tudes, is here allowed, because no field has yet been met with 

 which did not support a considerable bui'den of it. 



n 



