Travers. — Presidential Address. 115 



but I cannot find that any of these is charged with this duty 

 within high southern latitudes. Great results are, however, 

 expected by the Bureau from their present effort, and the 

 maritime world is to be congratulated upon the important 

 initiative thus taken up by the French Government. 



A similar difficulty exists as regards modern investigations 

 into the shape of our globe. It will be in your recollection 

 that, during the last year's proceedings of this society. General 

 Schaw read a paper pointing out that these investigations, 

 like those last alluded to, are completely blocked for want of 

 data from the Southern Hemisphere. Hitherto we have been 

 content to look upon the earth as having the form of a ball, 

 flattened at the poles, and to treat this flattening as following 

 regular meridional curves, extending north and south from 

 every point on the equator. It has, however, been demon- 

 strated that this is by no means a correct view, but rather 

 that our globe presents considerable irregularities of shape, 

 both local and general, especially towards the poles, and that 

 pendulum swingings made at various places in polar regions 

 are absolutely necessary before reliable measurements of the 

 earth's diameters can be made, correct diameter measurements 

 being, in effect, the necessary bases of all measurements in 

 astronomy. Pendulum swingings are now the recognised 

 means for determining the extent of local deviations from the 

 ideal form above alluded to, and very precise methods have 

 lately been elaborated for utilising such swingings, which are 

 found to afford rapid and exact means for the purpose in view. 

 It is stated that not more than seven pendulum swingings have 

 yet been made beyond the 50fch parallel of south latitude, none 

 of which were made within the antarctic circle, and hitherto 

 all efforts at determining the exact shape of the earth have 

 failed for want of them. 



In 1867 the late Mr. Proctor drew attention to the perma- 

 nent low barometer of the south temperate zone, and pointed 

 out, in part explanation, that the centre of gravity for the 

 solid portions of the earth lay somewhat to the south of the 

 centre of figure. He stated that this explanation had long 

 been received as accounting for two remarkable geographical 

 features, — namely, the prevalence of water over the Southern 

 Hemisphere, and the configuration of nearly all the peninsulas 

 over the whole globe. He stated, moreover, that, in his view 

 of its causes, it was immaterial whether or not those portions 

 of the antarctic regions which had not then been explored 

 were occupied chiefly by land, or whether the unexplored 

 north polar regions were or were not chiefly occupied by a 

 north polar ocean. But, although the existence of the low 

 barometer in the temperate parts of the Southern Hemisphere 

 has been long known, no generally-received explanation of its 



