ATMOSPHEROLOGY.^ — TEMPEllATUKE. 36l 



been no particular cause to affect it, — then the mean 

 temperature of latitude 76*45' near the western 

 coast of Spitzbergen, would have been 33» 8 instead 

 of 18°.8, as shown by my observations, and the mean 

 temperature of the Pole would have been about 

 31* *. Now, the difference between the mean tem- 

 perature of latitude 76° 45' by observation and cal- 

 culation, which is here 15°, may be considered as 

 the frigorific effect of the ice, because there is no 

 other known cause why there should be any differ- 

 ence at all. But if the ice be the sole cause of the 

 anomaly, it must chiefly produce its effect through 

 the medium of those winds which brush over its 

 surface f , whilst the mild winds from the south and 

 east, will generally bring a temperature uninfluenced 

 by it, and consequently tending to elevate the mean 

 temperature above what it would be in a situation 

 in the ice, so remote from the sea, that the milder 

 winds could never reach it unchanged. Now, 

 at the Pole, no wind whatever could convey the 

 mild influence of a temperate climate, because, from 



* I here follow Kiuwan, who, from Mayer's formula, cal- 

 culates the temperature of latitude 77* at 33.7^ and of 76* 

 at 34.1 ; hence 76° 45' or 76 f ° = 33.8. Professor Leslie, in 

 the second edition of his Geometry, p. 496. calcvJates the 

 temperature of 76° 45' at 34°.7, assuming that of the North 

 Pole at 32'. 



t The effect of what has been called Radiation, being incon- 

 siderable, under a dense atmosphere, subject to ahnost daily 

 obscurities by snow or fog, is not here brought into considera- 

 tion. 



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