1825.] Mathematical Principles of Chemical Philosophi/. 121 



silver 43, copper 38, iron 34, lead 24, zinc 23, tin 17, carbon 

 about '39 ; but in order to compute correctly tbe conducting 

 power of bodies, tbeir radiating power must be experimentally- 

 ascertained; because it enters into the calculation. The law 

 according to which caloric is conducted is easily determined ; 

 it is this : — If a solid rod be heated at one end, and distances 

 be taken in arithmetical progression, the excess of temperature 

 above that of the surrounding medium will decrease at those 

 distances in geometrical progression. 



The results of these investigations I consider as approxima- 

 tions whereby the general laws of chemical action are developed ; 

 and until these shall be correctly known, the corrections which 

 the numbers require cannot be made. By electric energy, I 

 mean no more than the fact, that bodies have definite tendencies 

 to the poles of the galvanic series. If the particles of all bodies 

 possess definite electrical states, the relation of the force of 

 gravitation to electrical energy is clear ; but this would give 

 rise to results which are inconsistent with the known principles 

 of philosophy ; for it would follow that no solid can be simple, 

 which may be the case; but since such hypothesis is totally 

 unsupported by any evidence whatever, it cannot be admitted : 

 also two masses of the same matter would be incapable of 

 attracting each other, the contrary of which is fully proved by 

 the experiments of Mr. Cavendish, and more decisive evidence 

 cannot be desired : besides, if two bodies, A and B, both posi- 

 tive, attract a negative body, C, the force of A being greater 

 than that of B ; A and B will also attract each other, and the 

 force will be proportional to the difference of their electric state ; 

 whereas in all cases the force is proportional to the quantities of 

 matter : these phenomena militate against the hypothesis of the 

 existence of electric energies. But if we suppose such a rela- 

 tion to exist between gravitation and electricity, that those 

 bodies which have the greatest tendency to the earth are most 

 powerfully attracted by the positive pole, all the phenomena 

 admit of perfectly easy solution, and by electric energy nothing 

 more will be meant than the relative tendencies of bodies to the 

 poles of the battery, which is the sense in which 1 have used the 

 terra ; and upon this hypothesis, chemical attraction, as well as 

 cohesion, capillary attraction, adhesion, and gravitation, will 

 depend upon, and be determined by the quantity of matter, to 

 which there is evidence, that the phenomena of electric action 

 may be reduced. I remain, Gentlemen, yours, &c. 



J. B. Emmett. 



