PROCEEDINGS 



THE ROYAL IRISH ACADEMY. 



1840. No. 26. 



December 14, 1840. 

 Rev. J. H. TODD, D.D., Vice-President, in the Chair. 



Dr. Apjohn read the following notice, by George J. 

 Knox, Esq., of " some Improvements in the Voltaic Pile." 



" The chief imperfection in the voltaic pile, its want of a 

 constant uniform power of long duration, by which it is rendered 

 almost useless as an instrument of reseai'ch, having been 

 overcome by the ability of Professor Daniell, the only thing 

 that remained to render it efficient seemed to be, to increase 

 its power; a desideratum accomplished by Mr. Grove, by sub- 

 stituting for copper and sulphate of copper, platinum and ni- 

 tric acid. To give to Grove's battery a constancy of action 

 equal to that of Professor Daniell's, would require an increase 

 in the quantity of acids, (particularly the sulphuric,) into 

 which the metals are immersed ; but inasmuch as in galvanic 

 batteries of the ordinary construction an increase of acid so- 

 lution would require an increased distance of the metals 

 from each other, producing a diminution of intensity, I endea- 

 voured to obviate these disadvantages by the following con- 

 trivance. Porous vessels are fixed half an inch apart in lateral 

 wooden supports, in which grooves are cut, to retain the zinc 

 plates from touching ; the porous vessels are filled with ni- 

 tric acid, from a long glass tube, sealed at one end, and bent 



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