260 
MESSRS. R. T. GLAZEBROOK AND E. B. SARGANT ON THE 
current ran when the deflection of the galvanometer was observed, was determined by 
direct comparison with the Elliott box. 
The values 
3060-71 B.A. units 
and 
3060-90 B.A. units 
were obtained as the means of several determinations on two different occasions. 
The mean is 
S=3060-80 
The value of V was determined by comparison with the B.A. coil Flat, using the 
form of bridge devised by Professor Fleming. 
We found on four separate occasions the values 
1-00096 
1-00096 
1-00095 
1-00098 
The temperature throughout at which these values are correct is 12°. 
These methods involve the use of the resistance boxes, and, of course, there must 
be some uncertainty in the temperature of the coils in the interior of the box. 
Another series of determinations, therefore, was made of the values of it and S, in 
which the boxes were only used to determine the values of certain small corrections. 
There is at the laboratory a coil of about 24 B.A. units—the standard used by Lord 
Rayleigh in his experiments on the value of the B.A. unit. This he had compared 
with the B.A. units and found that at 12° its value was 23"92820. He suggested 
that we should compare our standard of about 160 units directly with it, and this was 
done by one of us (R. T. G.). 
I first determined ab initio the value of the 24 ohms in terms of the B.A. units. 
I found by a method to be afterwards described the three values 
and 
The mean is 
23-92807 
23-92810 
23-92850 
23-92822 
which is practically identical with that found some months previously by Lord 
Rayleigh. 
Now the ratio of 24 to 160 is between 1 : 6 and 1 : 7. 
I therefore arranged a Wheatstone's bridge in the following manner;— 
<0 O 
