LOW BAROMETER OF ANTARCTIC ZONE. 303 



we have to account ; and. indeed, so far as the com 

 parison between the northern and southern temperate 

 zones is concerned (and this is the true question at 

 issue), we are only entitled to consider the third part 

 of an inch lost by overflow, as the true measure of the 

 efficiency of this cause. 



So far as I am aware, the theory I am about to pre 

 sent in explanation of the phenomenon of a low antarctic 

 barometer is original. It is sufficiently simple; 

 perhaps, if we remember how very seldom physical 

 phenomena admit of a simple explanation, one may 

 say that the theory labours under the disadvantage of 

 simplicity. 



It is obvious that the centre of gravity of the solid 

 portion of the earth s globe lies somewhat to the south 

 of the centre of figure. This arrangement has long 

 been accepted as the explanation of two remarkable 

 geographical features the prevalence of water over 

 the southern hemisphere, and the configuration of 

 nearly all the peninsulas over the whole globe. Whether 

 or not those parts within the antarctic regions which 

 have not yet been explored, are occupied by land 

 (chiefly) is a question which has little more bearing on 

 our views respecting this point than has the counter 

 question whether the unexplored north-polar regions 

 are or are not occupied by a north-polar ocean. 1 Sup- 



1 Captain Maury holds the affirmative on both points. I have already 

 had occasion to discuss in these pages his theory of a tidal north-polar 

 ocean, and I think the theory cannot be maintained. But the theory of 

 a polar ocean communicating with the Atlantic and Pacific is a sufficiently 



