458 NOTICES OF THE MEETINGS [June 9, 
hypothesis endeavours to account for. As the hypothesis of Am- 
pere could not account for diamagnetic action, some assumed that 
magnetic and electric force might, in diamagnetic matter, induce 
currents of electricity in the reverse direction to those in magnetic 
matter; or else might induce currents where before there were none : 
whereas in magnetic cases it was supposed they only constrained 
particle-currents to assume a particular direction, which before were 
in all directions. Weber stands eminent as a profound mathe- 
matician who has confirmed Ampére’s investigations as far as they 
proceeded, and who has made an addition to his hypothetical views ; 
namely, that there is electricity amongst the particles of matter, 
which is not thrown into the form of a current until the magnetic 
induction comes upon it, but which then assumes the character of 
current, having a direction the contrary to that of the currents 
which Ampére supposed to be always circulating round magnetic 
matter; and so these other matters are rendered diamagnetic. 
De la Rive, who has recently most carefully examined the various 
hypotheses, and who as an experimentalist and discoverer has the 
highest right to enter into the consideration of these deep, searching, 
and difficult enquiries, after recalling the various phenomena which 
shew that the powers concerned belong to the particles of matter 
and not to the masses merely, (the former conferring them by 
association upon the latter,) then distinguishes magnetic action 
into four kinds or modes,— namely, the ordinary, the diamagnetic, 
the induction of currents, and the rotation of a ray; and points out 
that any acceptable hypotheses ought to account for the four modes of 
action, and, it may be added, ought to agree with, if not account 
for, the phenomena of electro-chemical action also. De la Rive 
conceives that as regards these modes of action this hypothe- 
tical result may be obtained, and both Ampére and Weber's views 
also retained in the following mannev. All the atoms of 
matter are supposed to be endowed with electrical currents of 
a like kind, which move about them for ever, without diminution 
of their force or velocity, being essentially a part of their nature. 
The direction of these currents for each atom is through one 
determinate diameter, which may therefore be considered as the 
axis. Where they emerge from the body of the atom they divide 
in all directions, and running over every part of the surface 
converge towards the opposite end of the axis diameter, and 
there re-enter the atom to run ever through the same course. 
The converging and diverging points are as it were poles of 
force. Where the atoms of matter are close or numerous in a 
given space, (and chemical considerations lead to the admission 
of such cases,) the hypothesis then admits that several atoms 
may conjoin into a ring, so that their central or axial currents 
may run one into the other, and not return as before over the 
surface of each atom: these form the molecules of magnétic 
matter, and represent Ampére’s hypothesis of molecular currents. 
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