PLATES. 



I. Illustrative of Professor Carnelley's Paper on the Periodic Law. 



II. Illustrative of Professor E. Wiedemann's Paper on the Electric 

 Discharge in Gases. 



III. Illustrative of Professors Ayrton and Perry's Paper on the Gas- 



Engine Indicator-Diagram. 



IV. Illustrative of Sir A. Campbell and Mr. W. T. Goolden's Paper on 



a " Speed Indicator '" for Ship's Propellors. 



V. Illustrative of Mr. II. H. Hoffert's Paper on a new Apparatus for 

 Colour-Combinations. 



VI. Illustrative of Mr. H. A. Miers's Paper on the Hemihedrism of 

 Cuprite. 



VII. Illustrative of Mr. D. J. Blaikley's Paper on the Velocity of Sound 

 in Air. 



VIII. Illustrative of Mr. A. M. Worthington's Paper on the Surface 

 Forces in Fluids. 



IX. Illustrative of Mr. J. Hopps's Paper on the Alterations in the Elec- 

 trical Resistances of Metallic Wires, produced by Coiling and 

 Uncoiling. 



X. Illustrative of Prof. J. Loudon's Paper on Geometrical Methods in 

 the Theory of Refraction at one or more Spherical Surfaces. 



