56 THE FIGURE OF THE EARTH 



himself with the consequences which follow from the 

 tetrahedral deformation of a sphere is to experiment 

 with a hollow indiarubber ball. Among some of the 

 more interesting results which will then appear is the 

 connexion between the three longitudinal ridges (corre- 

 sponding with America, Africa, and Australia) and the 

 quoin representing the Antarctic continent. Although in 

 the actual case of our planet this connexion can no longer 

 be perceived, it is believed by many geologists on zoologi- 

 cal evidence to have existed in past times. 



A still earlier attempt to refer the irregularities of the 

 earth's form to a polyhedral figure was made by Elie de 

 Beaumont, * who was led to suppose that a pentagonal 

 dodecahedron best represented the facts. His views are 

 now generally regarded as of merely historical interest, 

 and it would be impossible to maintain them in matters 

 of detail ; on the other hand, a very remarkable and 

 unexpected correspondence can be traced between the 

 general symmetry of de Beaumont's figure, as orientated 

 by him, and that which we have been led to adopt. 

 Three contiguous faces lie symmetrically placed over 

 our land hemisphere ; they meet along edges which are 

 not far from coincidence with the triradial lines we have 

 drawn extending through Africa, and these three edges 

 intersect at a point not very far from our morphological 

 centre of the land hemisphere. On the other side of 

 the globe three contiguous faces lie symmetrically over 

 the oceanic hemisphere, while the remaining six faces 

 form a girdle, which corresponds to our Pacific zone of 

 land. Thus we seem to encounter another instance of 

 the existence of a common germ of truth in theories 

 widely different and at first sight opposed, a not infre- 

 quent phenomenon in the history of science. 



* "Notice sur les Systemes de Montagnes," by L. Elie de 

 Beaumont, Paris. 1852. 3 vols., duodecimo. 



