492 J. Trowbridge—Method of freeing a Magnetic Bar, etc. 
Tasie I. 
Resistances Degrees 
in ohms. of divergence, Difference. 
16 ¥ " 
32 14 8 
48 22 8 
54 30 
In the following Table II, the same resistances were intro- 
duced into a closed circuit, the strength of which was measured 
by the same instrument used as a tangent galvanometer: 
Tass IT. 
Resistances Degrees 
in ohms. of divergence. Difference. 
ue et 68°5 9 
“16 66°5 25 
“32 64 2 
“48 62 9 
"54 60 
It will be seen that, estimated in this way, the new method is 
much the more sensitive. It possesses the advantage also that 
the needle can remain at zero even while a strong current 18 
passing through the galvanometer; and is in a position, at the 
same time, to be influenced by the slightest change in the elec- 
trical condition of the closed circuit. : 
The method supplies a magnetic horizontal 
ndulum for the investigation of the induc 
It also 
2. 
as tive effects of large magnetic masses. _ 
e f\ serves to determine the force of attraction of a 
Unbbee coil on a magnet placed in Its axis. 
n the following figure the ellipse represents 
la 
Pe @/ makes an angle 6 with the vertical plane. 
i ta 
