( 671 ) 
in the oil so that the vanes were completely immersed and should 
experience no capillary action. But still we wished to know the order 
of magnitude of the forces brought into play by capillary disturbances; 
for this purpose we greatly magnified them. A damper as like ours as 
possible was filled only to such a height that the vanes and partitions 
intersected the surface of the liquid. The movable portion was suspended 
by a platinum-iridium wire 20 cm. long and 0,1 mm. thick; deflec¬ 
tions were read from a mirror on a scale 2 metres away. The oil 
vessel was placed successively in two different azimuths such that 
the approach of the vanes towards the partitions would bring into 
play 'couples of opposite moments. The scale deflection was 5 cm. 
The moment of the couple is therefore of the order of two thousandths 
of that of the couple exerted on the nickel ellipsoid. 
§ 5. Details of the observations. 
Nickel . 
The first series of measurements was made at 17°.2 C. 
TABLE II. 
H (gauss) /* (cm. of the scale) 
2230 89.42 
6250 89.97 
10270 90.12 
13280 90.34 
17760 90.50 
20300 90.66 
21540 90.79 
22760 90.81 
The scale reading was always corrected for the ratio of the tangent 
of the double angle to the double angle of the deflection. The zero 
as determined by the mean of readings to left and right remained 
constant to a few tenths of a millimeter. 
After this series the apparatus was accidentally damaged; it had 
therefore to be taken to pieces and remounted. That occasioned a 
small change in the magnitude of the deflections. Since the change 
of /* with H is determined by the foregoing series, only two points 
were subsequently determined at ordinary temperature before and 
after determinations in liquid hydrogen. 
