Boscovich regarded the constitution of matter differently. The ultimate atom was with him a point surrounded by powers of infinite elasticity. (See _Dr. Robisons Mechanical Philosophy_, for a full explanation of the theory of Boscovich.) The view entertained by Dr. Faraday, which will be comprehended from one or two short extracts from his valuable and suggestive paper, claims attention:-- “If the view of the constitution of matter already referred to be assumed to be correct--and I may be allowed to speak of the particles of matter, and the space between them (in water, or in the vapour of water, for instance), as two different things--the space must be taken as the only continuous part, for the particles are considered as separated by space from each other. Space will permeate all masses of matter in every direction like a net, except that in the place of meshes it will form cells, isolating each atom from its neighbours, and itself only being continuous.” Examining the question of the conducting power of different bodies, and observing that as space is the only continuous part, so space, according to the received view of matter, must be at one time a conductor, at others a non-conductor, it is remarked: “It would seem, therefore, that, in accepting the ordinary atomic theory, space may be proved to be a non-conductor in non-conducting bodies, and a conductor in conducting bodies; but the reasoning ends in this--a subversion of that theory altogether; for, if space be an insulator, it cannot exist in conducting bodies; and if it be a conductor, it cannot exist in insulating bodies.”--_A Speculation touching Electric Conduction, and the Nature of Matter_: by Michael Faraday, D.C.L., F.R.S., &c.: Philosophical Magazine, vol. xxiv. Third Series. See also Wollaston, _On the Finite Extent of the Atmosphere_.--Phil. Trans. 1822. Young, _On the Essential Properties of Matter_.--Lectures on Natural Philosophy. Mossotti, _On Molecular Action_.--Scientific Memoirs, vol. i. p. 448. CHAPTER II. MOTION. Are the Physical Forces modes of Motion?--Motion defined--Philosophical Views of Motion, and the Principles to which it has been referred--Motions of the Earth and of the Solar System--Visible Proofs of the Earth’s Motion on its Axis--Influence of the proper Motions of the Earth on the Conditions of Matter--Theory of the Conversion of Motion into Heat, &c.--The Physical Forces regarded as principles independent of Motion, although the Cause and often apparently the Effects of it. Many of the most eminent thinkers of the present time are disposed to regard all the active principles of nature as “modes of motion,”--to look upon light, heat, electricity, and even vital force, as phenomena resulting from “change of place” among the particles of matter; this change, disturbance, or motion, being dependent upon some undefined mover.[2]