60 LIFE AND ORGANISATION. 



point, and merely mention it here, as relating to one of 

 those great powers which are incessantly acting upon and 

 through life in all its forms. The same may be said of 

 Heat; the influence of which, in promoting organisation 

 and maintaining the vital functions, is familiar to us in a 

 thousand ways, and attested in more scientific form in every 

 part of animal physiology. The action of Light, as separate 

 from heat, is somewhat more ambiguous; but that it has 

 special effects on these functions cannot be doubted; and 

 very remarkable proofs of this are every day multiplying 

 upon us. We might almost deem sufficient as evidence, the 

 spectacle of the sudden bursting forth of life of all kinds 

 under the influence of a bright summer sunshine. But 

 science goes far beyond this, in showing that Light, like 

 Heat, does truly permeate and act upon those molecules of 

 matter, of which all bodies, organic or inorganic, are com- 

 posed. Much is yet to be learnt on this curious subject. 



Such are the general evidences and arguments of those, 

 who believe that we need look for no other vital principle 

 than lies in some modified function of the great forces which 

 we see in unceasing action around us, and feel to influence 

 at every moment the conditions of our own being. The fact 

 already noticed of their mutual convertibility, and other 

 various proofs that force may be hidden, latent, or altered in 

 aspect, but never effaced or lost, undoubtedly favour this 

 view. When its sensible effects disappear, we have cause to 

 believe that it is either operating in some way too minute for 

 our detection, or that it exists in a latent condition ready 

 for some new form of future developement. The advocates 

 of this doctrine are apt to startle us by their bold illustra- 

 tions. We feed a jaded horse on a peck of oats, and he is 

 able to travel again ; the effect, say they, of the evolution 

 and conversion into nerve force, of that power which has been 

 laid up in the grain during its growth. We light and warm 



