PLATES. 



I. Illustrative of Mr. C. Barus's Paper on the Fusion Constants of 



Igneous Rock. 



II. Illustrative of Dr. W. Pole's Paper on some unpublished Data on 



Colour-Blindness. 



III. & IV. Illustrative of Messrs. Edser and Stansfield's Paper on a 

 Portable Instrument for Measuring Magnetic Fields. 



V.-VIII. Illustrative of Mr. A. A. Michelson's Paper on the Application 

 of Interference Methods to Spectroscopic Measurements. 



IX. Illustrative of Prof. E. B. Kosa's Paper on the Specific Inductive 

 Capacity of Electrolytes. 



X. Illustrative of Lord Rayleigh's Paper on the Intensity of Light 



reflected from Water andMercury at nearly Perpendicular Incidence. 



ERRATUM. 

 Page 319, line 16, read .r= — 2a cos \6-\-a log cot \6. 



