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Some "Remarks on Electric Currents in Metalliferous Veins. By 

 Robert Were Fox, Esq. Communicated by the Author. 



I have been much interested by Professor Reich's report 

 of his researches on the electrical currents in metalliferous 

 A'eins, inserted in the last number of the Edinburgh '^i.^^v Phi- 

 losophical Journal ; and it is satisfactory to me to observe, that 

 his results are so much in accordance with my own. It is true, 

 that I did not obtain, as he has done, evidences of such cur- 

 rents on connecting ore-points with non-metalliferous rocks, 

 but this was, doubtless, owing to the inferior delicacy of my 

 galvanometer.* Notwithstanding this cu'cumstance, it was 

 sometimes acted upon very powei'fully Avhen two ore-points 

 were connected, far more so than it could have been by the 

 reciprocal influence of the copper plates, however near to- 

 gether they might have been placed, and yet they were, m 

 some instances, from 300 to 400 yards apart. IMoreover, when 

 a zinc plate was substituted for a copper plate, first at one of 

 the ore-points, and then at the opposite one, the du-ection and 

 intensity of the currents were unaffected by the change ;* 

 whereas they would have been in opposite directions had they 

 been generated by the mutual action of the plates ; their in- 

 tensity would also have been increased, and so it would, had 

 they arisen from an action between an ore-point, and one of 

 the plates. Besides, it should be recollected that the plates 

 could not have had any action whatever on each other when 

 in contact with ore-points, which were ^ood conductors of elec- 

 tricity, as they almost always were ; and when the points only 

 of the copper wires were employed instead of the plates, for 

 making the contact with the ores, the results in both cases 

 were the same. In one mine, electric currents produced by 

 a pair of large plates of copper and zinc plunged mto strong 

 brine, were made to traverse the long wires, and counteract 

 those derived from the vein itself. In those experiments it 



* A description of my galvanometer is given in Philosophical Transactions 

 1830, in note, p. 3»0. 



t See Fourth Report of tlic British Association for the Advancement of 

 Science, 1834, p. 673. 



