3 
” 
2 
yi 
M 
, 
x as 
‘ones F 
‘ae 
Supposed Polarity of Diamagnetic Bodies. 205 
perimental helix. Whether the cores act directly on the experi- 
mental helix or indirectly through their influence on the domi- 
nant magnet, is a very aig irgree — I have found. it. 
difficult to select expressions, t I wis to do so, whieh” 
should not in some degree eeindes that pate It seems to 
magnetic metals, raises them into power either permanently or 
transiently, and has their power for that time directed towards i 
ore the core moves to approach the magnet, the magnet and 
experimental helix are in close relation ; and the latter is situated .  «¢ 
in the intense field of magnetic force which belongs tothe pole 
of the former. If the core be iron, as it approaches the | magnet 
ing through the helix and across its convolutions, are competent 
to produce the currents in it which are obtained (2653. 2668. ). 
the iron retreats these lines of force diverge, and again cross-_ 
ing the line of the wire in the helix in a contrary direction to. ~ 
their former course, produce a contrary current. It does not seem_ 
necessary, in viewing the action of the iron core, to suppose any 
direct action of it on the helix, or any other action than this 
which it exerts upon the lines of force of the magnet. An such — <i 
a Case its action upon the helix would be indirect. 
2697. Then, by all parity of reasoning, when a copper | core 
enters the helix its action upon it should be — also. "For 
nat 
the currents which are produeed in it are caused by th e diréct Mes tee 
fluence of the magnet, and must react equivalently upon it. ia, “ 
they do, and because of their direction and paar. | action ei 
will cause the lines of force of the magnet to diverge. the the i. 
core diminishes in its velocity of motion, or cofhes to fest, dy 
currents in it will cease, and then the lines of force: pl eptiverse , : 
and this: divergence and convergence, or passage “In t 0. direc- 
pose: across the wire of the experimental heli is. idfficront to 
ice wig eae ‘which are obtain 
magnet, 67122673. es 
direc et by the retreat ag ¥ 
e Mie ; 
ction’ ft é cor re notof this, 
Tiger andaggss 
imes of the, éxperi-s @ - 
e ‘core and «dur 
te "A hic co per’ ee 68 long, 0-7 of an in 
externa al‘dfar ameter, and 0-1 ‘ef a bane internal diameter, and aa 
»,Seuenty 0-3 of an shy ie sides, was placed i 
fae ee helix, and‘ Estseire core (2668. ).u 
‘Sul, whagever the’ form of the en 
