328 Mr. Galbraith on the Figure of the Earth. 



Pendulum. 



3943329-2-0-5835803 j/=E 10 

 39-15163— 2-0*6680546 j/=En 

 39-16772— z— 0-7474900 */=E 12 

 39-18213-*— 0*8194250j/=E 13 

 39*19553— z-0-8816350 2/=E l4 

 39*20600-2-0*9321740j/=E 15 



Whence z = 39*098334 — 0-4067622 y (A) 



Again, 



0-0000000 — 0-0000000 z — O'OOOOOOOj/ = E 



0-2924964— 0-0074963^— 0-0000562 j/=Ei 



1-1614649-0-0297652 ■* — 0*0008860#=E 2 



2-5820970-0-0661582 2— 0*0043769^= E 3 



4*5130098-0*1156039 2— 0*0133643 ?/=E 4 



6*8987431— 0*1766568 2-0*0302076 */=E 5 



9*6688209— 0*2475060 2-0*061 2592 j/=E 6 



12-7425870— 0-3260503 2— 0-1063088 ?/=E 7 



16*0283042— 0-4099407 2— 0-16805143/=E 8 



19-4272624-0-4966596 2-0*2466707 j/=E 9 



22-8374171 -0-5835803 2-0-3405660 j/=Eio 



26-1554265— 0-6680546 2-0-44629703/=En 



29-2774790-0-747490O2-0-5587402j/=E 12 



32-1068169-0-8194250 2-0*6714573 < 2/=E 13 



34*5561511— 0*8816350 2— 0*7772800 j/=E ]4 



36*5468138 — 0*9321740 2— 0*8689486 j/=E 15 



Whence z = 39-1498536 — 0-6598551 y (B) 



Equating (A) and (B) there will result 



y = 0-20348 and z = 39*015576 



therefore 2- — 0*0052153, and 



z 



E = 0-0086082 - 0*0052153 = 0*003393 =5 ^ y *. 



Adopting the formula for the length of the pendulum, or 

 I = 2 + y sin 3 (A — 0), the lengths of the pendulum by com- 

 putation may be compared with the foregoing means derived 

 from experiment. 



* As there is some reason to believe that several of the pendulums near 

 the equator are too great ; if the first three of those above be rejected, then 

 the ellipticity will be -y^.. Indeed, I have for some time been induced to 

 consider -^fay to be that which must ultimately be generally adopted. 



Lat. 



