Published posthumously in 1888, this treatise by the first Cavendish Professor of Physics at Cambridge explores and explains the fundamental principles and laws that are the basis of elementary physics. Maxwell was at the forefront of physics and mathematics during the nineteenth century and his pioneering work brought together existing ideas to give 'a dynamical theory of the electromagnetic field'. This work inspired not only the applications of electromagnetic waves like fibre optics but also Einstein's theory of relativity. The text explains many of Newton's laws and the unifying concepts that govern a body and its motion. The increment in the complexity of topics allows one to build a solid understanding of the accepted laws of mathematical physics that explain topics like force, work, energy and the centre mass point of a material system. This logical guide and instruction is as timeless as the laws of physics that it explains.