SECT. XXXIV. MAGNETISM A DUAL POWER. 335 



SECTION XXXIV. 



Magnetism a Dual Power Antithetic Character of Paramagnetism and 

 Diamagnetism The Earth Paramagnetic Properties of Paramagnetic 

 Bodies Polarity Induction Lines of Magnetic Force Currents 

 of Electricity induced by them Proved to he Closed Curves Analogy 

 and Identity of Electricity and Magnetism Terrestrial Magnetism 

 Mean Values of the Three Magnetic Elements Their Variations in 

 Double Progression proved to consist of Two Superposed Vaiiations 

 Discovery of the Periodicity of the Magnetic Storms The Decennial 

 Period of the Magnetic Elements the same with that of the Solar Spots 



Magnetism of the Atmosphere Diamagnetism Action of Electro- 

 Magnetism on Paramagnetic, Diamagnetic Bodies, and on Copper, very 

 different Proof of Diamagnetic Polarity and Induction Magne- 

 crystallic Action Effects of Compression, Heat, and Cleavage on Mag- 

 netic Bodies Mutual Dependence of Light, Heat, Electricity, &c. &c. 



The Conservation of Force and the Permanency of Matter Primary 

 Laws of Nature Definition of Gravity not according to that Law 

 Gravity only the Residual Force of a Universal Power Magnetism of 

 the Ethereal Medium. 



MAGNETISM may be regarded as a new science in consequence 

 of the profound researches and admirable discoveries of Dr. Fara- 

 day. Since the magnetism of matter is only known by the 

 action of a magnet or of electricity upon it, by using an ex- 

 tremely energetic magnet or electro-magnet he has proved that 

 all known substances, whether solid, liquid, or aeriform, are more 

 or less magnetic, but that the magnetism is very different in 

 different substances. For example, if a bar of iron be freely sus- 

 pended between the poles of a very powerful magnet or electro- 

 magnet, it will be attracted by both poles, and will set or rest 

 in the direction of a straight line joining them ; but if a similar 

 bar of bismuth be freely suspended in the same manner, it will 

 rest in a direction at right angles to that which the iron bar 

 assumed. Thus the direction in which the iron sets is axial or 

 in the line of force, while that which the bismuth assumes is 

 equatorial or perpendicular to the line of force. Substances that 

 are magnetic after the manner of iron are said to be paramag- 

 netic, those that are magnetic after the manner of bismuth are 

 diamagnetic. As far as we know, all matter comes under one or 



