CONTENTS. VU 



Page 

 Physics. 



Mr. J. S. Stuart Glennie on the Application of the Principle of the Conser- 

 vation of Force to the mechanical explanation of the Correlation of Forces... 26 



Professor W. Thomson's Physical Considerations regarding the Possible Age 

 of the Sun's Heat 27 



Light, Heat. 



Sir David Brewster on Photographic Micrometers 28 



■ on the Compensation of Impressions moving over the 



Retina 29 



on the Optical Study of the Retina 29 



on Binocular Lustre 29 



Mr. J. Alexander Davies's Observations upon the Production of Colour by 

 the Prism, the Passive Mental Effect or Instinct in comprehending the En- 

 largement of the Visual Angle, and other Optical Phenomena 31 



Mr. Thomas Rose on Presentations of Colour produced under novel conditions; 

 with their assumed relation to the received Theory of Light and Colour 32 



Mr. William Thomas Shaw's Method of interpreting some of the Pheno- 

 mena of Light 33 



Mr. John Smith on the Chromascope, and what it reveals 33 



■ on the Prism and Chromascope 33 



Mr. Thomas Sutton on the Panoramic Lens 33 



Mr. H. H. Vivian's Microscopic Observations on the Structure of Metals 34 



Mr. J. J. Walker's Observations on an Iris seen in Water, near Sunset 35 



Electricity, Magnetism. 



The Astronomer Royal on Spontaneous Terrestrial Galvanic Currents 35 



■ on the Laws of the Principal Inequalities, Solar and 



Lunar, of Terrestrial Magnetic Force in the Horizontal Plane, from obser- 

 vations at the Royal Observatory, Greenwich, extending from 1848 to 1857... 36 



Mr. Latimer Clark and Sir Charles Bright on the Formation of Stand- 

 ards of Electrical Quantity and Resistance 37 



Mr. J. P. Gassiot on the Deposit of Metals from the Negative Terminal of an 

 Induction Coil during the Electrical Discharge in Vacuo 38 



Professor Hennessy on a Probable Cause of the Diurnal Variation of Magnetic 

 Dip and Declination , 39 



Mr. Fleeminq Jenkin on Permanent Thermo-Electric Currents in Circuits of 

 one Metal 39 



Rev. H. Lloyd on the Secular Changes of Terrestrial Magnetism, and their 

 Connexion with Disturbances 41 



Mr. C. W. Siemens on an Electric Resistance Thermometer for observing 

 Temperatures at inaccessible situations 44 



Messrs. Archibald Smith and F. J- Evans on the Effect produced on the 

 Deviation of the Compass by the Length and Arrangement of the Compass 

 Needles ; and on a New Mode of Correcting the Quadrantal Deviation 45 



Mr. F. J. Evans on H.M.S. Warrior's Compasses 45 



Mr. B. Stewart on the Photographic Records given at the Kew Observatory 

 of the great Magnetic Storm of the end of August and beginning of Septem- 

 ber 1859 47 



