Physics. eet 
It is next proved that the diamagnetic excitement produced by one 
pole of a magnet is not the state which set a pole of an opposite 
quality to repel the substance :—that each pole induces a condition pe- 
culiar to itself, or, in other words, that the “excitement of diamagnetic 
bodies in the magnetic field is of a dual cha 
hese points being ean, a Selnthinnss co mparison is instituted 
alone ; secondly, when operated on by the current alone ; and, thirdly, 
when operated on by the magnet and current combined. "A bar of iron 
was, in some of these cases, compared wit th a fire of bismuth, but it 
of re 
__ A bar of this substance, cut in a certain manner from the crystal 
mass, exhibits between the poles of a magnet apes: the same visible 
_ deportment asa bar of iron, while it is wall known that pele 
_ deportment of Appt is opposed to that of iron. Th ea n his 
_ examination of the points before us, divided eping ie bar nid two 
4 distinct classes, and classified diamagnetic bars -same manner ; 
one class he called normal, and the other class abnormal, A normal 
_ paramagnetic bar is one _ poi its i pole to pole in the 
magnetic field, anda normal d e which sets its length 
is hasan magnetic bar, 
ih ‘equa han ; while an ab- 
ets its length axially. 
magnet nit the current 
fat right angles to the line joi ca poles. 
on the contrary, is one pre sets its | 
a cial current, the former sets its 
et and -c 
found that the tiapostidt of forces which produces a deflection from 
tight to left of the <cunnarae bar produces a deflection from 
If t 
But if the ao of the no rmal paramagnetic bar be compared 
“te that of the abnormal diamagnetic one, it will be found that they are 
cases identical ; and the same identity of deportment is exhibited 
bi is abnormal paramagnetic bar is compared with the normal dia- 
one. The necessity of paying attention to structure in exper- 
it 
