LIST OF ILLUSTKATIONS. 
Plate 1.—Professor H. B. Dixon on the Rate of Explosion in Gases. 
Plates 2 to 4.—Mr, E, H. Griffiths on the Value of the Mechanical E(|uivalent of 
Heat, deduced from some Experiments performed with the view of establishing 
the relation between the Electrical and Mechanical Units; together with an 
Investigation into the Capacity for Heat of Water at different Temperatures. 
Plates 5 to 16.—^Mr. T. Gray on the Measurement of the Magnetic Properties of 
Iron. 
Plates 17 and 18.—Dr. J. T. Bottomley on Thermal Radiation in Absolute Measure. 
Plates 19 to 23.—Lieut.-General R. Strachey on Harmonic Analysis of Hourly 
Observations of Air Temperature and Pressure at British Observatories.—Part I. 
Temperature. 
Plates 24 and 25.—Professor W, Ramsay and Dr. J. Shields on the Variation of 
Molecular Surface-Energy with Temperature. 
Plates 26 to 30,—Professor J. N. Lockyer on the Photographic Spectra of some of 
the Brighter Stars. 
Plates 31 and 32.—Dr. O. J. Lodge on Aberration Problems.—A Discussion concern¬ 
ing the Motion of the Ether near the Earth, and concerning the Connexion 
between Ether and Gross Matter; with some new Experiments. 
Plate 33.—Professor J. Prestwicii on the Evidences of a Submergence of Western 
Europe, and of the Mediterranean Coasts, at the (dose of the Glacial or so-called 
Post-glacial Period, and immediately preceding the Neolithic or Recent Period, 
Plates 34 to 41.—Professor J. A, Ewing and Miss H, G. Klaassen on Magnetic 
Qualities of Iron. 
