THE LAW OF SUBSTANCE. 475 



"The truths of science are thus coming into evident accord with 

 those doctrines of religious belief which are common to all creeds. We 

 are, however, as far as ever from the determination of the question 

 whether those higher forms of force and energy have quantivalent rela- 

 tions and intertransformability; although a belief that mind and matter 

 have a certain identity, and that in matter can be discerned 'the promise 

 and potency of all terrestrial life/ has been avowed, explicitly or im- 

 plicitly, by more than one great thinker when wandering into the realms 

 of speculation." 



In this, Tyndall long anticipated our contemporary writers.* 

 Lavoisier showed to the satisfaction of the scientific men of his time 

 that matter is indestructible, whatever the apparent result of chemical 

 action. Faraday, and probably many among his predecessors, recog- 

 nized that the forces are indestructible, and that great investigator 

 wrote: 



"To admit that force may be destructible, or can altogether disap- 

 pear, would be to admit that matter could be uncreated; for we know 

 matter only by its forces/'f 



Liebig fully recognized the distinction between the proper use, of 

 the term, force and energy, and usually called the latter 'power/ as when 

 he says: 



"Man by food not only maintains the perfect structure of the body, 

 but he daily inlays a store of power and heat, derived in the first in- 

 stance from the sun. This power and heat, latent for a time, reappears 

 and again becomes active when the living structures are resolved by the 

 vital processes into their original elements."^ 



Carpenter clearly saw these distinctions and recognized the nature 

 of energy, as distinguished from force, when, in his discussion of the ac- 

 tion of the vital forces, he asserted: 



"What the germ really supplies is not the force but the directive 

 agency; thus rather resembling the control exercised by the superintend- 

 ent builder, who is charged with working out the designs of the archi- 

 tect, than the bodily force of the workmen who labor under his guidance 

 in the construction of the fabric." § 

 Carpenter says explicitly: 



"Hence we seem justified in affirming that the correlation between 

 heat and the organizing forces of plants is not less intimate than that 



* See his 'Heat Considered as a Mode of Motion,' N. Y., D. Appleton & Co., 

 1864, for an admirable statement of this point and for his splendid championage 

 of Mayer. 



f 'The Conservation of Force.' 



I 'The Connection and Equivalence of Force.' 



§ 'The Correlation of Vital and Physical Forces.' 



