CONTENTS. Vll 



Page 

 Professor Tyndall on the Establishment of Thermometric Stations on Mont 



Blanc 56 



General Physics. 



Mr. J. S. Stuart Glennie, Proposal of a General Mechanical Theory of 



Physics 58 



Rev. Dr. Macvicar on the Philosophy of Physics 59 



Instruments, &c. 



Mr. Joseph Beck on producing the Idea of Distance in the Stereoscope 61 



Mr. A. Claudet on the Stereoscopic Angle 61 



on the Stereomonoscope 61 



on the Focas of Object-Glasses 61 



on a Changing Diaphragm for Double Achromatic Combina- 

 tions 62 



Professor J. Clerk Maxwell on an Instrument for exhibiting the Motions of 



Saturn's Rings 62 



Abbe Moigno on a New Photometer . 62 



M. Ruhmkorff on a New Electro-Medical Apparatus 62 



Abbe Moigno on Becquerel's Phosphoroscope 62 



on the Phonautograph, an Instrument for registering Simple and 



Compound Sounds 62 



M. Porro's Portable Apparatus for Analysing Light 63 



Lieut.- Colonel R. Shortrede on an Improvement in the Proportional Compass 63 



Mr. Thomas Sutton on a New Photographic Lens, which gives Images 



entirely free from Distortion 63 



Mr. H. R. Twining on the Angular Measurement of the Picture in Painting . 64 



CHEMISTRY. 



Address by Dr. Lyon Playfair, President of the Section 65 



Mr. Binney on the Solubility of Bone-earth from various Sources in Solutions 



of Chloride of Ammonium and Common Salt 66 



Mr. G. B. Buckton on Pentethyl-stibene 66 



Dr. F. Crace Calvert and R. Johnson on the Specific Gravities of Alloys... 66 

 Dr. Bialloblotzky on the different Points of Fusion to be observed in the 



Constituents of Granite 68 



Dr.F. Crace Calvert on the Formation of Rosolate of Lime on Cotton Fabrics 



in Hot Climates 68 



Dr. Dalzell on Crystallized Bichromate of Strontia 68 



on the Economical Preparation of Pure Chromic Acid..... 68 



Dr. Guthrie's Reports from the Laboratory at Marburg 68 



Dr. J. H. Gladstone on the Fluorescence and Phosphorescence of Diamonds 69 

 on Photographs of Fluorescent Substances 69 



MM. Isoard and Son on a New Form of Instantaneous Generator of Illumi- 

 nating Gas by means of Superheated Aqueous Vapour and any Hydrocarburet 



whatever 69 



Mr. J. B. Lawes and Dr. J. H. Gilbert on the Effects of different Manures 



on the Composition of the Mixed Herbage of Meadow-land 70 



