73 ^ Hi ley . On the Value of Different Degrees of 
Experiment 6. May 9, 1912. 9.25 a.m. to 8.30 p.m. 
•Temp. = 20 0 C. 
Radius of rotation at middle of box =15 cm. 
0 = ioo°. 
Total period (/+ T ) — 1 1 m. 
t 
Y = 7 * 97 - 
R — 3-61. 
Point of equilibrium is 1 cm. below middle of box. 
r — 14 cm. 
Cent, force = 7 ‘3 4 mg. 
C = 7.40 mg. 
Thus 1 = 7 . 97; £ = y . 4 o. 
C 7 7 
_ 0 ,Q, 
mg. t yD 
Experiment 7. June 21, 1912. 10.20 a.m. to 6.40 p.m. 
Temp. = 21 0 C. 
Radius of rotation at middle of box = 15 cm. 
6 = 1 oo°. 
Total period (/+ T) = 11 m. 
t 
Y = 7 * 94 * 
R = 3-82. 
Point of equilibrium is 1-5 cm. below middle of box. 
r - * 3 - 5 - 
Cent, force = 7*93 mg. 
C = 7.98 mg. 
And M.E.C. — i*oo. 
t C 
Thus — = 7 * 94 , — = 7 - 98 - 
CT 
= i-oi. 
mg.t 
Experiment 8. July 29, 1912, 10.20 p.m., to July 30, 10.40 a.m. 
Temp. = 20 0 C. 
Radius of rotation at middle of box = 20 cm. 
6 = 96°. 
Total period (/+ T) = 11 m. 
/ 
Y = I0 '°- 
R — 3.69. 
Point of equilibrium is 1 cm. below middle of box. 
r = 19 cm. 
Cent, force = 10-42 mg. 
C = 10-46 mg. 
