He then goes on to develop the idea in relation to different intensities of the magnetic field. I must, however, refer the reader to the paper itself for fuller details. In his greatest work,[34] writing on this subject, he says: “I think we have good evidence for the opinion that some phenomenon of rotation is going on in the magnetic field, that this rotation is performed by a great number of very small portions of matter, each rotating on its own axis, being parallel to the direction of the magnetic force, and that the rotations of these different vortices are made to depend on one another by means of some kind of mechanism.”
From the foregoing extracts taken from Maxwell's writings, we learn that the constitution of the Aether, as given in [Art. 44], exactly coincides with, and satisfactorily fulfils the conditions that he lays down with reference to his physical conception of the lines of force around a magnet or electrified body.
So that the theory of Maxwell is not merely hypothetical, as is suggested by scientists, but exactly describes the conditions and state of the atomic Aether medium which surrounds all magnets. We have, however, seen that the sun is a magnet, and therefore it possesses around it on every side, the same as any other magnet, these aetherial lines of force composed of infinitesimal vortices, or mere whirling points which correspond to an aetherial atom.
These aetherial lines of force stretch out into space on every side of the sun, and in fact form concentric magnetic shells around the sun; which magnetic shells coincide with the equipotential surfaces of the Aether viewed merely from the point of elasticity and density of the medium. We learn by experiment, that these lines are closest together nearest to the magnet, which fact agrees with the statement that Aether is gravitative, and therefore the Aether would be densest nearest the sun. That is, the atoms would be pressed closer together, so that the lines of force of which these atoms are composed ought also to be closer together at the surface of the magnet, which we find by experiment is the case. As the sun is an electro-magnet, therefore, it possesses these magnetic lines of force on all sides, forming a series of magnetic shells. We have now arrived by the aid of Maxwell's theory to a physical conception of the Aether from a magnetic standpoint, which fully agrees with our physical conception of the Aether which was arrived at by purely philosophical reasoning, based on Newton's Rules of Philosophy.
Thus we are able to combine into one whole by our conception that Aether is matter, and therefore atomic and gravitative, not only Faraday's Lines of Force, but also Maxwell's physical conception of the same, apart from the solutions given to the other problems of science by the self-same conception, which solutions will be dealt with in their proper order.
As further evidence of Maxwell's belief in the physical existence of Faraday's Lines of Force, let me again quote from his paper on “Action at a Distance,“[35] already referred to in [Art. 43]. He writes: “Its minute parts may have rotatory as well as vibratory motions, and the axes of rotation form those lines of Magnetic Force which extend in unbroken continuity into regions which no eye has seen.... These lines must not be regarded as mere mathematical abstractions. They are the directions in which the medium is exerting tension like that of a rope, or rather like that of our own muscles.“
[33] Exp. Res.
[34] Magnetism and Electricity.
[35] Collected Works, by Niven.