In his study of conduction of heat James Maxwell observed that quantities which are significant in such a study are 'temperature, flow of heat and conductivity. Further, he noticed that the mathematical laws of the uniform motion of heat in homogeneous media are identical in form with those of attractions varying inversely as the square of the distance. He thought source of heat, flow of heat and temperature correspond respectively to centre of attraction, accelerating effect of attraction and potential. On this ground, Maxwell observed that conduction of heat proceeds by an action between contiguous parts of a medium.
Which one of the following best explains Maxwell's method?