42 DR. FARADAY’S EXPERIMENTAL RESEARCHES IN ELECTRICITY. (SERIES XXVI.) 
(2832.), and therefore I accept the converse phenomena as to place and position of 
a diamagnetic body (2812. 2813.) as proof that it has less power of transmitting the 
magnetic force than the space it occupies, and from that conclude that it conducts 
diamagnetically (2802.). 
2844. The separation of paramagnetic bodies in the equatorial direction is a proof 
of the manner in which, by their better conduction, they disturb the position of the 
lines of force in the medium around them (2831.). The separation of two diamag- 
netic bodies, under the same circumstances, is an equal proof of the manner in which, 
by difference of conducting power, they also disturb the disposition of the force (2831.). 
The equatorial attraction of a paramagnetic and a diamagnetic body for each other, 
when they are in a medium, which in conducting power is between the two (2831.), 
is a proof not only of conduetion in both, but also of their reverse condition in respect 
of each other and the medium. 
2845. The place of a crystal of bismuth, either nearer to or further from the mag- 
netic axis (2841.), according as its magnecrystallic axis is parallel or perpendicular to 
the axial line, is also a case of the difference of conducting power, and therefore of 
the possession of that power by the diamagnetic body. Many other cases might be 
quoted in illustration of the existence of that power which I assumed as conducting 
power ( 2797 .), and which probably nobody may be inclined to deny. I will suppose 
that the above are enough to explain my meaning. 
2846. It is hardly necessary for me to say that magnetic conduction does not mean 
electro-conduction, or anything like it. The very best electro-conductors, as silver, 
gold and copper, are below mere space in their ability to favour the transmission of 
magnetic force, so deficient are they in what I have called magnetic conduction. 
There is a striking analogy between this conduction of magnetic force and what I 
formerly called specific inductive capacity (1252. &c.) in relation to static electricity, 
which I hope will lead to further development of the manner in which lines of power 
are affected in bodies, and in part transmitted by them. 
^ iv. Atmospheric magnetism*^. 
2847. It is to me an impossible thing to perceive, that two-ninths of the atmo- 
sphere, by weight, is a highly magnetic body, subject to great changes in its magnetic 
* A most important paper by Professor Christie “ On the Theory of the Diurnal Variation of the Magnetic 
Needle,” appears in the Philosophical Transactions for 1827, p. 308. Led by the discoveries of Seebeck in 
thermo-magnetism and the experiments of Gumming, he was induced to search how far the idea of thermo- 
currents or thermo-magnetic polarity would apply to the natural phenomena, and concludes (p. 327), that, 
admitting that the earth and the atmosphere are substances in which such action can under any circumstances 
take place, these experiments would indicate that any portion of the earth bounded by parallel planes with the 
atmosphere surrounding it, would become similarly polarized if one part were more heated than another. Thus 
considering alone the eguatorial regions of the earth, we should have two magnetic poles on the northern side, and 
on the southern side two poles similarly posited ; the poles of different names being opposed to each other on the con- 
trary sides of the equator. 
t I ought to refer the readers of my paper to a theory of the cause of the daily variations by M. A. de la 
