46 THE FIGURE OF THE EARTH 



endians." A prediction from general principles was now 

 in conflict with an inference drawn from actual observa- 

 tion : induction and deduction were opposed. It was 

 impossible that both could be right, and the French 

 Government, with a view to deciding the controversy, 

 sent out two expeditions to make a renewed appeal to 

 fact by fresh measurements of meridional arcs. One 

 expedition was despatched to Lapland, the other to 

 Peru. The result was to prove that Newton was 

 right ; deduction had triumphed over induction, and 

 that not for the first time nor the last in the history 

 of science. 



With continued improvements in the methods of 

 measurement, which are always in progress, and with 

 the multiplication of these measurements, our know- 

 ledge of the earth's form may be expected to become 

 increasingly exact. Already in 1878 Colonel Clarke, as 

 a result of a laborious discussion of the then existing 

 data, was led to the conclusion that the earth is not 

 quite a true spheroid, but an ellipsoid with three unequal 

 axes, one of the equatorial diameters being slightly 

 longer than another at right angles to it. The longer 

 axis intersects the surface in Africa. While Colonel 

 Clarke placed the extremity of the axis in longitude 

 8 15' W., General Schubert placed it in longitude 

 41 4' E., or 49 19' more to the east, but otherwise 

 their results were in general agreement. In the dis- 

 covery of this apparently trivial divergence from a true 

 spheroidal form observation had outrun explanation, and 

 the fact, if it be a fact, remained for a long time isolated 

 and barren. 



Quite recently, however, it has acquired a new and 

 unexpected importance, for the inequality is just what 

 might have been anticipated, if the novel hypothesis of 

 Mr. Jeans should prove to be sound. There is a particu- 



