268 Dr. C. R. A. Wright and Mr. C. Thompson. [Dec. 15, 



December 15, 1887. 



Professor Gr. G. STOKES, D.C.L., President, in the Chair. 



The Presents received were laid on the tahle, and thanks ordered 

 for them. 



The President read a letter from ELM. Secretary of State for Home 

 Affairs, annonncing that Her Majesty had " been gracionsly pleased 

 to command that the Royal Society be allowed to enjoy the privilege, 

 on all fit and proper occasions, of presenting their addresses to the 

 Sovereign on the Throne." 



The President was requested to convey to the Home Secretary the 

 thanks of the Society for his communication, and to express their 

 satisfaction that Her Majesty had been graciously pleased to honour 

 the Society with this mark of the Royal recognition. 



The following Papers were read : — 



I. 4; Note on the Development of Feeble Currents by purely 

 Physical Action, and on the Oxidation under Voltaic In- 

 fluences of Metals .not ordinarily regarded as spontaneously 

 oxidisable." By C. R. Alder Wright, D.Sc, F.R.S., 

 Lecturer on Chemistry and Physics, and C. Thompson, 

 F.C.S., F.I.C., Demonstrator of Chemistry, in St. Mary's 

 Hospital Medicai School. Received November 24, 1887. 



In the course of a series of further experiments ou cells set up with 

 " aeration plates " (plates simultaneously in contact with the air and 

 the electrolytic fluid used in the cells — ' Roy. Soc. Proc.,' vol. 42, 

 p. 212), we have made a large number of determinations of the E.M.Ps. 

 developed with incorrodible aeration plates of various kinds (e.g., 

 platinum foil, spongy platinum, thin sheet gold, &c.) when opposed to 

 the same oxidisable metal, such as copper or zinc, in contact with the 

 same electrolytic fluid, e.g., dilute sulphuric acid or caustic soda 

 solution. The details of these observations, when completed, will 

 form the subject of a future paper; whilst making them we have 

 noticed that if two or more different kinds of aeration plates be set up 

 on the surface of the fluid contained in a shallow basin in which the 

 oxidisable metai is immersed, and sufficient time be allowed to elapse 

 to enable the films of air attracted to the aeration plates to attain a 



