J. Nicklés on Magnetisation. 101° 
Distance between the poles. Current a. Current 6. Current ¢, Current d. 
i tad ag bee paper, “ kil. 10 kil. 17 kil. = 45 kil. 
0:0005 14-15 22 52 
0025 .- : ‘ 1 16 23 55 
0-045 i oe Ap 18 25-26 58-59 
0-120 - > . 9 18 27 65 
0:220 ‘ : 7 18 27 @ 66 
0-280 - 5 15 27 66 
These results ‘establish another analogy between the bifurcate 
electromagnets and the rectilinear, It is seen that the numbers 
which express the magnetising power increase at first regularly 
as in the last ;* that they then decrease after passing a pes 
point, variable with the intensity of the current or with the | wis 
netism developed, and whose range augments with these 1 
sities, 
The residual magnetisms of the electromagnets employed ex- 
hibits the same relation after the Mbp of — current ; 
the armature falls spontaneously w are at a small 
distance from one another ; it remains = enspiltied. when this dis- 
tance is increased ; finally it falls Spe when the separation has 
reached a certain point. SS 
nalogous facts have , Eve with a circular electromag- 
nit construct ted L thas? consists _- 2) of two disks of iron 
‘aa’ 9 centimeters in diameter, and 2 in thickness, excavated to a 
depth of 8 millimeters ; these. two disks are put on an axis m, 35 
m. in diameter ; the helix A is wound on the middle of this 
axis, aud the helix made narrow so as to be enclosed by the disks ; 
