Page:A Treatise on Electricity and Magnetism - Volume 2.djvu/11

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Part III.

Magnetism.

Chapter I.

Elementary Theory of Magnetism.

Art. Page
371. Properties of a magnet when acted on by the earth 1
372. Definition of the axis of the magnet and of the direction of magnetic force 1
373. Action of magnets on one another. Law of magnetic force 2
374. Definition of magnetic units and their dimensions 3
375. Nature of the evidence for the law of magnetic force 4
376. Magnetism as a mathematical quantity 4
377. The quantities of the opposite kinds of magnetism in a magnet are always exactly equal 4
378. Effects of breaking a magnet 5
379. A magnet is built up of particles each of which is a magnet 5
380. Theory of magnetic 'matter' 5
381. Magnetization is of the nature of a vector 7
382. Meaning of the term 'Magnetic Polarization' 8
383. Properties of a magnetic particle 8
384. Definitions of Magnetic Moment, Intensity of Magnetization, and Components of Magnetization 8
385. Potential of a magnetized element of volume 9
386. Potential of a magnet of finite size. Two expressions for this potential, corresponding respectively to the theory of polarization, and to that of magnetic 'matter' 9
387. Investigation of the action of one magnetic particle on another 10
388. Particular cases 12
389. Potential energy of a magnet in any field of force 14
390. On the magnetic moment and axis of a magnet 15