74 



CHARLES S. SLICHTER 

 q* a* 



'• 



«))*■ 



a' \ 3(1 — q a cot ^ 



in which e is the ellipticity of the stratum whose mean radius is 



1 ii- ■ • r 1 r 1 2.4605 z 

 a, e is the ellipticity or the surface, and q= 



La Placm/v Law or De^/s/ry. 



£LL/PT/C/T/ES OF- <3t&ATA CoAffA/r'SD W/rs/ iSo/?&4CeI/>1£</£& 



Fig. 3. 



1 See Thompson and Tait, II, p. 410; Pratt, Figure of the Earth, 4th ed., p. 115; 

 Clarke, Geodosy, p. 84. 



