CONTENTS. 



I. Experimental Researches in Electricity. — Eleventh Series. By Michael Faraday, JE^^^'., 



D.C.L. F.R.S., Fullerian Prof. Chem. Royal Institution, Corr. Memh. Royal 

 and Imp. Acadd. of Sciences, Paris, Petersburgh, Florence, Copenhagen, 

 Berlin, 8^c. ^c. . page 1 



II. Fourth Letter on f^ottaic Combinations, with reference to the Mutual Relations of 



the Generating and Conducting Surfaces. Addressed to Michael Faraday, Esq., 

 D.C.L. F.R.S., Fullerian Prof. Chem. Royal Institution, 8^c. S^c. &;c. By 

 J. Frederic Daniell, F.R.S., Prof. Chem. in Kings College, London. . 41 



III. Of such Ellipsoids consisting of homogeneous matter as are capable of having the 



resultant of the attraction of the mass upon a particle in the surface, and a cen- 

 trifugal force caused by revolving about one of the axes, made perpendicular to 

 the surface. By James Ivory, K.H. M.A. F.R.S. L. 8^ E. Instil. Reg. Sc. Paris. 

 Corresp. et Reg. Sc. Gottin. Ccyrresp 57 



IV. Researches towards establishing a Theory of the Dispersion of Light. No. IV. 



By the Rev. Baden Powell, M.A. F.R.S. F.G.S., Savilian Professor of Geo- 

 metry in the University of Oxford 67 



V. On the Colours of Mixed Plates. By Sir David Brewster, K.G.H. F.R.S. . 73 



VI. Supplementary Note to Experimental Researches in Electricity. — Eleventh Series. 



By Michael Faraday, Esq., D.C.L. F.R.S., Fullerian Prof. Chem. Royal 

 Institution, Corr. Memb. Royal and Imp. Acadd. of Sciences, Paris, Petersburgh, 

 Florence, Copenhagen, Berlin, 8^c. ^c 79 



VII. Experimental Researches in Electricity. — Twelfth Series. By Michael 



Faraday, Esq., D. C.L. F.R.S., Fullerian Prof Chem. Royal Institution, Corr. 

 Memb. Royal and Imp. Acadd. of Sciences, Paris, Petersburgh, Florence, Copen- 

 hagen, Berlin, 8^c. Sfc 83 



VIII. Experimental Researches in Electricity. — Thirteenth Series. By Michael 



Faraday, Esq., D.C.L. F.R.S., Fullerian Prof Chem. Royal Institution, Corr. 

 Memb. Royal and Imp. Acadd. of Sciences, Paris, Petersburgh, Florence, Copen- 

 hagen, Berlin, Sfc. 8^c 125 



