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XIII. Experimental Researches in Voltaic Electricity and Electro-Magnetism. 
By the Rev. William Ritchie, LL.D. F.R.S. Professor of Natural and Ex¬ 
perimental Philosophy in the Royal Institution of Great Britain, and Professor 
of Natural Philosophy and Astronomy in the University of London . 
Read January 19, 1892. 
The splendid discoveries which have lately been made in magnetism and 
electro-magnetism have so much engaged the attention of philosophers, that 
the theory and laws of action of voltaic electricity, no longer possessing the 
charms of novelty, have been entirely neglected. The subject appearing to me 
full of interest, and lying at the very foundation of a large portion of physical 
science, induced me to undertake an experimental investigation of some of the 
most important points connected with it, the result of which I have the honour 
of laying before the Royal Society. 
PART I. 
ON THE LAWS OF ACTION OF AN ELEMENTARY BATTERY. 
1. Volta was led to the invention of the pile by what he conceived to be 
the discovery of a new power in nature, viz. the development of electricity by 
the simple contact of dissimilar metals. Other philosophers have denied the 
existence of this power, and have substituted that of chemical action in its 
stead ; whilst a third class still maintain that both powers are concerned in the 
production of voltaic effects. We have lately had a series of experiments by 
M. Matte ucci to prove that motions could be excited in the limbs of a frog 
by carefully washing it in distilled water, and then acting on it with discs of 
copper and zinc. These experiments were intended to prove that galvanic 
action resulted from the simple contact of dissimilar metals, without the aid 
of chemical action, and that consequently the theory of Volta was well founded. 
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