Vol. 12. OCTOBER 1881. No. 75. 



Published the First Day of every Month. — -Price 2s. 6d. 



THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of Tilloclis 'Philosophical Magazine? 

 Nicholson's 'Journal? and Thomsons 'Annals of Philosophy.'' 



CONDUCTED BY 



SIR ROBERT KANE, LL.D. F.R.S. M.R.I.A. F.C.S. 

 SIR WILLIAM THOMSON, Knt. LL.D. F.R.S. &c. 



AND 



WILLIAM FRANCIS, Ph.D. F.L.S. F.R.A.S. F.C.S. 



FIFTH SERIES. *^ 



N° 75.-OCTOBER 1881. 

 WITH THREE PLATES. 



X 



Illustrative of Mr. T. Gray's Paper on the best Arrangement of the 

 Wheatstone's Bridge for the Measurement of a particular Resistance. 



LONDON: 



PRINTED BY TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET, 



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