84 II INDUCTION IN ROTATING SPHERES On differentiation these become or 30 2n-1 = 2n - σφα = σφι d do o2n+2 d do o)- d o2n+2 d do .0). do 2n 4"-274 - Φι 2n = - Φα P2" -P2' = $1. If we put =2n+1, we get for the equations + 2n+2- Φι σ 2n+2. $ Þ₂" + σ = - = $2 = $1, which equations again lead to the p's and q's. The constants may be determined in the same way as before, and then we find - = - 2n+1 2(n+1)(2n+1)¸2n+3 - - In-1(XS)In( − λo) – In-1( − λS)In(λo) In-1(AS)In+1(As) - In-1 - AS)In+1(As) - The formula becomes especially simple for the case where S∞, that is, when we have to deal with a spherical hollow in an infinitely extended mass. Then In-1(AS) = 0, and we get - = - - 2(n + 1)(2n+1)02n+ = s2n+3 In (λo) In+1(As) If we may neglect upσ in comparison with unity, on account of the small value of w, we may put for the q's their values for small arguments (p. 77). We then obtain - $1 √ − 1 − $₂ = X²e ¯ Mo − s),