IHO TROF. TROUTOX AND MR. XOBLE OX THE MECHAXICAL FORCES ACTIXC4 
The following table gives the final results obtained. These were oliser vat Ions 
taken after many months of experience with the apparatus, and were consldeied by 
us as conclusive against there being any such efiect as we were seeking. 
Azimuth of Condenser + 45°, 
Pate. 
Time. 
Potential in 
volts. 
March 9 . . . 
12 .1.0 I’.lNt. 
2100 
9 . . . 
G r.M. 
2100 
„ 10. . . 
12 (day) 
2100 
„ 10 . . . 
3 P.M. 
2100 
„ 10 . . . 
6 P.M. 
2100 
„ 12 . . . 
12 (day) 
2100 
„ 12 . . . 
3 P.M. 
2100 
12 . . . 
6 P.M. 
‘ 2100 
”, 13 . . . 
.0.30 P.M. 
2100 
„ 13 . . . 
6.30 P.iu. 
1 2100 
„ 18 . . , 
3 I’.M. 
2000 
Deflection 
Deflection 
Deflection 
calculated 
calculated 
observed. j 
(annual motion). 
(annual -!- proper). , 
1 
('cntims. 
ceiitiins. 
cent i ms.. 
- 2 • G 
- 6-8 
-0-3.O 1 
+ 0-8 
0-0 
-0-12 ! 
-2-6 
-6-8 
-0-34 ; 
- 1-2 
-3-4 
-0-23 
+ 0-8 
0-0 
-0-26 
-2-6 
-G-8 
-0-36 
- 1-2 
-3-4 
- 0 • 2.0 
+ 0-8 
0-0 
-0-32 
+ 0-8 
0-0 
-0-.34 
+ 0-8 
0-0 
-0-18 
-1-2 
-3-4 
-0-02 
Tlie laro-est observed deflection, •36 centlm., barely exceeds 5 per cent, of the 
calculated deflection, 6‘8 centlms. 
The following observations, taken l)etween Marcli 13 and March 18, illustrate the 
behaviour of the apparatus as regards electrostatic effects. These justity^ the 
conclusion that the effect observed was the result of residual electrostatic action,* 
and could in no vary lie attributed to the relative motion of the eaitli and the lethei. 
The sign of the charges was reversed at times. 
The Insulation was good. 
Ilate. 
Potential. 
Sign of suspension. 
Ileflection. 
March 13 ... . 
1100 
negative 
+ 0-05 
1100 
positive 
-0-01 ! 
: 18.... 
1100 
slight + ' 
1100 
negative 
4-0-01 1 
1.500 
11 
4-0-04 1 
1500 
positive 
4-0-16 ! 
1500 
+ 0 -13 ; 
1.500 
negative 
+ 0-24 
1500 
+ 0-14 
1 
1500 
po.sitive 
-0-09 j 
* It niio-ht l)e thought, ;it first sight, that the magnetic fichl produced hy the moving condenser might 
interact with the earth’s magnetie field; that no such action exists has heen shown by FitzGkrai.u 
(‘Scientific Papers,’p. 111). We are therefore justified in concluding that the residual action did not 
arise from disturbances due to the earth’s magnetic field. 
