1875.] On the Replacement of Metals in a Voltaic Cell 47 



November 25, 1875. 



Dr. J. D ALTON HOOKER, C.B., President, in the Chair. 



In pursuance of the Statutes, notice was given from the Chair of the 

 ensuing Anniversary Meeting, and the list of Officers and Council pro- 

 posed for election was read as follows : — 



President. — Joseph Dalton Hooker, C.B., M.D., D.C.L., LL.D. 



Treasurer. — "William Spottiswoode, M.A., LL.D. 



s . _ f Professor George Gabriel Stokes, M.A., D.C.L., LL.D. 



1 Professor Thomas Henry Huxley, LL.D., Ph.D. 



Foreign Secretary. — Professor Alexander William Williamson, Ph.D. 



Other Members of the Council. — Professor J. Couch Adams, LL.D. ; 

 Major-General John T. Boileau ; Edward Viscount Card well, F.G.S. ; 

 Warren De La Eue, D.C.L. ; Captain Erederick J. O. Evans, R.N., C.B. ; 

 Edward Erankland, D.C.L. ; Albert C. L. G. Giinther, M.A., M.D. ; 

 Professor T. Wharton Jones, E.E.C.S. ; Joseph Norman Lockyer, 

 E.E.A.S. j The Eev. Eobert Main, M.A. ; Professor Daniel Oliver, E.L.S. ; 

 Professor Edmund A. Parkes, M.D. ; Eight Hon. Lyon Playfair, C.B., 

 LL.D. ; William Pole, C.E., Mus. Doc. ; The Eev. Bartholomew Price, 

 M.A. ; Warington W. Smyth, M.A. 



The Presents received were laid on the table, and thanks ordered for 

 them. 



The following Papers were read : — 



I. " On the Eeplacement of Electro-positive by Electro-negative 

 Metals in a Voltaic Cell." By J. H. Gladstone, Ph.D., F.R.S., 

 Eullerian Professor of Chemistry in the Royal Institution, and 

 Alfred Tribe, Esq., Lecturer on Chemistry in Dulwich Col- 

 lege. Received July 31, 1875. 



It is well known that one metal exerts a greater chemical force than 

 another, and is capable of displacing it from its combinations. Among 

 those metals with which we are familiar, potassium is looked upon as the 

 most powerful ; and it is a certain fact that calcium, barium, strontium, 

 aluminium, and magnesium have been isolated by its agency. It could 

 scarcely be expected, therefore, that any other metal could directly replace 

 potassium. If such should happen, we would have an instance of rever- 

 sal, and should expect to find, on examination of the conditions, an agent 

 capable of doing just the reverse work of what is usually assigned to affinity. 



It is also well known that in a simple voltaic cell, such as zinc con- 





