Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. The grand theory of the conservation of energy is only now in its youth, and the principle of the atomic structure of matter is scarcely out of its cradle. The idea of a universe composed of atoms, linked together by some medium and in ceaseless motion, and that on the character of this motion depend heat, light, electricity, magnetism, chemism, sound, &c., is only now Shaping itself into form in the mind of the philosopher.