294 NERVOUS FORCE. LECT. XIV. XV. 



I can show you in another way the great advantage 

 which results from the transformation of chemical action 

 into nervous force in an animal. 



I endeavoured to measure the amount of mechanical 

 work obtained, when applying to the nerves of a frog a 

 current produced during the oxydisation of a given quantity 

 of zinc in a pile. Here are the numbers obtained : three 

 milligrammes of zinc, oxydising in one day, furnish a cur- 

 rent which, if we suppose that it could be continually ap- 

 plied to the nerves of a frog, would produce a muscular 

 power equal to 5-419 kilogrammes, raised to one metre in 

 height during the same interval of time. It is probable that 

 these numbers are far from being accurate, and I intend 

 hereafter to repeat these experiments : it is, however, certain, 

 that the causes of error are all one way, and tend to repre- 

 sent as much smaller than it really is, the effect produced 

 by the three milligrammes of zinc. 



The same quantity of zinc burnt, would yield a quantity 

 of heat, which employed in forming steam, would execute 

 work equivalent only to O k , 8304, raised to one metre. 



Finally, the current produced by the three milligrammes 

 of zinc was applied to an electro- magnetic machine; and 

 in this case we obtained O k , 96, raised to one metre. 



Everything, then, leads us to the conclusion that the 

 mechanical work developed by chemical action, and trans- 

 formed into nervous force, in an animal, is very great ; and 

 that in all the machines which man has invented he is al- 

 ways, and will perhaps for a long time to come, far from 

 attaining that degree of perfection which exists in those ma- 

 chines which we know not how to imitate and can only 

 admire.* 



* In the Comptes Rendus for the 15th of March, 1847, Matteucci has 

 drawn up the following summary of his hypothetical views respecting the 

 nervous force : * &- 



