REPLY TO CRITICS. 37 



From the above table we see that it is only in that 

 area lying between the equator and latitude 35° that 

 the southern hemisphere has a lower mean tempera- 

 ture than the northern. But it is from this area that 

 the enormous amount of heat transferred to the 

 northern hemisphere is mainly derived. Were the 

 transference of heat to cease, the temperature of this 

 area would be very considerably raised, and that of 

 the corresponding area on the northern hemisphere 

 lowered. The result would doubtless be that the 

 southern hemisphere down to the equator would then 

 be warmer than the northern. But, even as things 

 are, as Mr. Ferrel remarks, "the mean temperature of 

 the southern hemisphere is the greater of the two," 

 the mean temperature of the southern being 60 o, 89 F. 

 and that of the northern 59 0, 54 F. 



Heat cut off by the Atmosphere. — Professor New- 

 comb says further, "Another idea of the author which 

 calls for explanation is that solar heat absorbed by the 

 atmosphere is entirely lost, so far as warming any 

 region of the globe is concerned." This is no idea of 

 mine. My idea is not that the heat cut off is entirely 

 lost, but merely that the greater part is lost. A large 

 portion of the heat is reflected, and of that absorbed 

 one half, perhaps, is radiated back into space and lost, 

 in so far as the earth is concerned. 



