CONTENTS (continued). 



ill. Preliminary Note on Experiments in Electro-Photometry. By Professor^** 1 

 James Dewar, F.R.S., Jacksonian Professor University of Cambridge . 354 



IV. On the Determination of the Scale Value of a Thomson's Quadrant Elec- 

 trometer used for Registering the Variations in Atmospheric Electricity 

 at the Kew Observatory. By Gr. M. Whipple, B.Sc, Superintendent 

 of the Kew Observatory . . . 35g 



v 9, 1878. 



I. On the Action of. Sonorous Vibrations in varying the Force of an Electric 



Current. By Professor D. E. Hughes 3G2 



II. Note on the Minute Anatomy of the Thymus. By Herbert Watney, 



M.A., M.D., Cantab. . . . . . . '359 



III. On the Classification of Loci. By W. K. Clippord, F.R.S., Professor of 



Applied Mathematics in University College, London . . . .370 



IV. Harmonic Analyzer. Shown and explained by Sir William Thomson, 



F.R.S., Professor of Natural Philosophy in the University of Glasgow . 371 



May 16, 1878. 



I, Experimental Researches on the Electric Discharge with the Chloride of 

 Silver Battery. Part II. The Discharge in Exhausted Tabes. By 

 Warren De La Rue, M.A., D.C.L., E.R.S., and Hugo W. Muller 



Ph.D., F.R.S. . . ." '374 



II. Note on Legendre's Coefficients. By I. Toe-hunter, F.R.S. . . . 381 



III. On the Spectra of Metalloids. Spectrum of Oxygen. By Arthur 



Schuster, Ph.D., F.R.A.S , 333 



IV. On the Variations of the Diurnal Range of the Magnetic Declination as 



recorded at the Prague Observatory. By BAlpour Stewart, LL.D., 

 F.R.S., Professor of Natural Philosophy at Owens College, Manchester 389 



List of Presents . . . . . . . . . . . 402 



ERRATA. 



Page 78, lines 13 and 27, and page 79, line 16, for Greenwich-Hew read, 

 Kew- Greenwich. 

 Page 119, line 8, for hypochloric read hydrochloric. 



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