KINETIC OK MECHANICAL VIEW OF NATLllK. 79 



iietic, and galvanic phenomena, such as Coulomb's electro- 

 static and magnetic laws, Ampere's electro-dynamic and 

 electro-magnetic formulie, and Ohm's anil Faraiiay's laws 

 referring to galvanic currents, and many othei-s. It 

 liad also to give an intelligible representation of t!ie 

 elementary actions of which these complicated plienom- 

 ena are made np. In mder to arrive at the latter, the 

 method usually employed is to look for anabjgies in 

 other provinces of science where the desired uniticatiun 

 has already I'cen brought about. The great natural 

 philosophers of the French school who had so success- 

 fully accomplished the most extensive unification yet 

 attempted in any large branch of knowledge — tlie uni- 

 fication of physical astronomy under Newton's gravita- 

 tion formula — had tried to follow up this analogy in 

 Dther realms of research, and had developed what I 

 called in a former chapter tlie astronomical view of 

 natural phenomena. Ampere, and notably "Weber, had 

 extended this analogy so as to embrace electric and 

 magnetic phenomena. There was, however, another 

 analogy which was more familiar to the great experi- 

 mentahsts in this country, notal)ly to Faraday — namely, 

 the analogy of those various phenomena which depend 

 on processes of emanation, of a gradual spreading out, 

 of a How or conduction: tliose plieiumiena where the 

 factor of time comes in, and where an apparently sta- 

 tionary condition is brought about by a mode of motion, 

 or what has been termed a " dynamic equilibrium." 

 Thomson, starting from Fourier's mathematical analysis 

 of sucli processes, had been led to sec bow far-reaching 

 this analogy is, and bad latterly (1852) extemied it to 



