394 THE CONNECTION AND EQUIVALENCE OF FOKCES. 



pound of water, generates a magnetic force capable of ele- 

 vating a weight of 13 J cwt. to the height of one foot. 



If the metallic wire through which the electricity is cir- 

 culating, be cut, and both ends immersed in water, a chemical 

 decomposition of the water into hydrogen and oxygen takes 

 place. The circulating electricity is converted into chemical 

 affinity, and into a power of attraction which causes the sep- 

 aration of the elements of water. With the evolution of the 

 hydrogen and oxygen all traces of the electrical current dis- 

 appear. The power to produce heat and magnetic force, the 

 usual effects of the electrical current, is apparently in this 

 case annihilated, and in its place we obtain two gases, one of 

 which, hydrogen, when burned in oxygen, reproduces water 

 and evolves heat. Now it has been proved, by careful ex- 

 periments, that an electrical current of a given strength, 

 which, when converted into heat in a conductor, is capable 

 of raising the temperature of a pound of water by one degree, 

 will produce by the decomposition of water a quantity of hy- 

 drogen, by the combustion of which one pound of water can 

 also be elevated one degree in temperature. f 



The heat and power of attraction which were apparently 

 lost by the decomposition of the water, had only become 

 latent, so to speak, in the elements of water. This heat is 

 again set free on the reunion of these elements, and if con- 

 verted into working power, would produce the same result 

 (viz., raising a given weight a foot high) as would have been 

 effected by a magnetic power generated by a quantity of elec- 

 tricity circulating round a bar of iron, equal to that which 

 was originally employed in the decomposition of the water. 



The electrical current is the consequence of a chemical 

 action, and the amount of electricity which circulates can 

 therefore be measured by the quantity of zinc which is dis- 

 solved. The chemical force (affinity) is converted by the 

 solution of the zinc into a corresponding quantity of elec- 

 tricity ; and this again in the conductor into its equivalent of 



