11 79 INDUCTION IN ROTATING SPHERES Using formula (a) (p. 77) we may divide out the q's and thus obtain 1 $1+$2 - 1 = δλ 1+ 2n+1 But now we have $8 4πRiw = = h, 2n+1 (2n+1)h according to our previous notation, and hence 1 - = h 1 1+h-1 = 1+ h² 1+h 2 √ — 1, which result agrees with the one previously obtained. Thus we have on the one hand tested our formula by means of a result already known; on the other hand we have proved that the previously given formulæ hold for all values of h, which proof still remained to be given. velocities 2. Secondly, we apply our formula to the case where we Small need only retain the first power of the angular velocity in f₁ of rotation. and f. For simplicity we restrict the investigation to a solid sphere. In this case we found 2n+1 Pr(λo) - = 2n Pn-1(AS) Expanding the p's and retaining only first powers we get 2+ - ƒ₂+ƒ₂√− 1 = 2n+3 - S2 2+ 2n+1 A closer consideration of this equation shows that the values of f,, f, thence found when substituted in merely give the inductions of the first and second order, which we have already calculated on p. 68. Here we only consider the