Whether Galvanifm he EleBricUyf- %fi^ 



in this proccfs would vary with the intenfity of the leading agent, as well as thofc m which, 

 the fpeed of the efFed: is governed by heat, dilutiopj &c. 



With an increafed pile placed in a vertical pofuion, Col. H. obtained V£ry weak (igns of 

 ele£tricity. He conne£ted the apparatus with the condu£l:or of an eledlrical machine, and 

 found the efFecl rather impeded than aflifled by the common ele£tric ftream. He placed 

 the plate of Bennet's eleftrometer in the circuit without producing eleftric figns. 

 He found than the galvanic apparatus placed between the outfide and infide of a jar pre- 

 vented its charging, and that it is alfo capable of conducting the charge, though not 

 rapidly : and on the whole, from the very minute exhibition of the attraftive and repellent 

 powers, while the caufticity, the fliock, and the oxidation, are io very powerful, he 

 cannot be perfuaded that electricity is the principal agent, though fonjic might be 

 generated, or difengaged during the operation of the apparatus. 



Before I attempt to give a numerical elucidation of the phenomena, I (hall take the 

 liberty to remark, i. that Col. Haldane'a eleftric ftream through the apparatus might have 

 been in the contrary direction to its own ftream; 2. that the current from an eleCtrical 

 machine may be incomparably lefs in quantity than that produced by the metals ; 3. that 

 the experiment with the cap of Bennet's eledtrometer was not arranged fo as to direCt the 

 fuppofed current through the leaves ; 4. that the pile muft in any hypothefis prevent a jar 

 from being charged higher than itfelf; 5. that Mr. Crulcklhank, of Woolwich, has 

 charged a large jar, fo as to give a fhock, merely by placing the pile between its coatings; 

 and, 6. laftly, whatever may be wanting in intenftty of eleftric force (upon which the 

 figns depend) may be made up by quantity. Whether the quantity be, indeed, fufficient to 

 account for what happens, muft be deduced from the faCts. I am aware of the great 

 difficulties which oppofe themfelves to our refearches into the laws by which the elec- 

 tric fluid is governed. All the experiments hitherto made, Including a. confiderable 

 number which have employed much of my time, but are ftill too incomplete for publica- 

 tion, are too few and too limited to ferve as the grounds for computation, or to be ex- 

 tended from that intenfity which affords a fpark of more than a foot in length, to thofe 

 minute variations of electrical power which are menfurablc by fparks too fliort to become 

 the objeCl of our fenfes. In the following lines, therefore, when I conGder the galvanic 

 phenomena, it is fimply my wifti to ftiew that they are not inconfiftent with deductions 

 made from the prefent ftate of our knowledge, though the quantities, upon future, and 

 more ftriCt examination, may turn out to be very different from what are here exhibited. 



The apparatus of Volta may be compared with the common Leyden jar, if we extend 

 by analogy the experiments of Cavendifh to all furfaces and intenfities. For fhocks nearly 

 equal will be given when the quantities of coated furface (or eleCtrical capacity) are direClly 

 as the fquares of the quantities of eleClricity, or inverfely as the fquares of the lengths of 



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