554 ANNUAL REGISTER, 1817. 



tance of 35 or 40 leagues, whereof 

 one-half was in contracted chan- 

 nels, amidst compact and formi- 

 dable ice. And, further, that in 

 less than a fortnight, while at 

 rest with regard to tlie ice, our 

 drift, as ascertained by astronomi- 

 cal observations, had been 60 or 

 70 miles to the south, and a dis- 

 tance equally as great to the west. 



Effects of the Ice on the Sea and 

 the Atmosphere. 



The profusion of ice in the polar 

 regions produces peculiar and 

 marked effects on the surrounding 

 elements. The sea, in conse- 

 quence, exhibits some interesting 

 characters, and the atmosphere, 

 some striking phenomena. Of 

 these, the power the ice exerts on 

 the wind, — on aqueous vapour, — 

 on the colour of the sky, — and on 

 the temperature of the air, are the 

 most prominent; and of those, 

 accordingly as the ice or swell has 

 the ascendancy, the results are 

 varied and remarkable. 



1. When the wind blows forci- 

 bly across a solid pack or field of 

 ice, its power is much diminished 

 ere it traverses many miles : in- 

 somuch, that a storm will fre- 

 quently blow for several hours on 

 one side of a field, before it be 

 perceptible on the other ; and, 

 while a storm prevails in open 

 water, ships beset within sight 

 will not experience one-half of its 

 severity. 



It is not xmcommon for the ice 

 to produce the effect of repulsing 

 and balancing an assailing wind. 

 Thus, wlien a severe storm blows 

 from the sea, directly towards the 

 main body of ice, an opposite 

 current will sometimes prevail on 



the borders of the ice 3 and such 

 conflicting winds have been ob- 

 served to counterpoise each other 

 a fevy furlongs distant from the 

 ice, for several hours : the vio- 

 lence of the one being, as it were, 

 subdued by the frigorific repulsion 

 and lesser force of the other. Tlie 

 effect resulting, is singular and 

 manifest. 



2. The moist and temperate 

 gale from the southward, becomes 

 chilled on commixture with the 

 northern breeze, and discharges 

 its surplus humidity in the thick- 

 est snow. As the quaotity of the 

 snow depends considerably on the 

 difference of temperature of the 

 two assimilating streams of air, it 

 follows, that the largest proportion 

 must be precipitated on the ex- 

 terior of the main body of ice, 

 where the contrast of temperature 

 is the greatest : and since that 

 contrast must be gradually dimi- 

 nished, as the air passes over the 

 gelid surface of the ice, much of 

 its superabundant moisture must 

 generally be discharged before it 

 reaches the interior. Hence we 

 can account for the fewness of the 

 clouds, — the consequent bright- 

 ness of the atmosphere, — and the 

 rareness of storms, in situations 

 far immured among the northern 

 ice. 



From this consideration, it might 

 be supposed, that after the preci- 

 pitation of a certain small depth 

 of snow on the interior ice, the 

 atmosphere could alone replenish 

 its moisture from the same sur- 

 face, and that whatever changes 

 of temperature might occur, it 

 could only discharge the same 

 again : or, in other words, that 

 the very same moisture would be 

 alternately evaporated and depo- 

 sited, 



I 



