Chap. 7] 



GRAVITATIONAL METHODS 



203 



in three, four, and five positions were taken. The formulas used in the 

 calculation of the three-position record were 



t/„ = 1.26[(A2 - A3) - (a;' - a'/) + 0.01044(a;' - a'/)] 



IJy, = 2.18[(A2 + A3) - (a;' + A'3') + 0.01044(a;' + a'/)] 



C/a = -3.60[(A2 - A3) + (a'/ + a'/) - 0.01233(a;' - a'/)] 



2[/^ = -6.24[(A2 + A3) + (a;' + A'3') - 0.01233(a;' + a'/)], 



where = 1.26, p = 2.18, q = 3.60, and r = 6.24, 0.01044 = 1 - s, and 

 0.01233 = 1 — t. These formulas are derived from the standard formulas 



Fig. 7-726. Torsion-balance calculation chart for Uxy and Uyz (after Slotnick). 



(7-52/i), which may be written C/„ = o(Ai — sAj) = o(Ai — A2-}- As — sAj), 

 and so on, so that 



t/.. = 0[(A2' - A3') - (a;' - a'/) -h (1 - s)(A;' - A^)] .... 



