▼1 CONTENTS. 



Page 

 Professor J. Thomson on recent Theories and Experiments on Ice at its Melt- 

 ing-point 23 



Professor W. Thomson on Electrical " Frequency" 26 



, Remarks on the Discharge of a Coiled Electric Cable.. 26 



on the Necessity for incessant Recording, and for 



Simultaneous Observations in different Localities, to investigate Atmospheric 

 Electricity 27 



Mr. G. V. Towleh on the Cause of Magnetism 28 



Mr. John T. Towson on Changes of Deviation of the Compass on Board Iron 

 Ships by "heeling," with Experiments on Board the 'City of Baltimore,' 

 'Aphrodite,' ' Simla,' and ' Slieve Donard ' 28 



Mr. J. J. Walker on the Iris seen on the Surface of Water 29 



Astronomy. 



Mr. G. B. Airy on the Present State and History of the Question respecting 

 the Acceleration of the Moon's Motion 29 



Mr. W. R. Birt on the Mid-day Illumination of the Lunar Craters Geminus, 

 Burckhardt, and Bernoulli 30 



Sir David Brewster on Sir Christopher Wren's Cipher, containing Three 

 Methods of finding the Longitude 34 



Sir C. Grey on the Longitude 34 



Mr. J. Pope Hennessy on the Inclination of the Planetary Orbits 34 



Mr. J. B. Lindsay on Chinese Astronomy 35 



Mr. Norman Pogson on an Improvement in the Heliometer 36 



on three Variable Stars, R and S Ursae Majoris, and 



U Geminorum, as observed consecutively for six years 36 



Mr. Daniel Vaughan on the Effects of the Earth's Rotation on Atmospheric 

 Movements 41 



Mr. A. S. S. Wilson on a System of Moving Bodies 43 



Meteorology. 



Mr. John Allan Broun on the Semidiurnal and Annual Variations of the 

 Barometer 43 



Mr. Alexander Brown on the Fall of Rain in Forfarshire 47 



Rev. Charles Clouston's Remarks on the Climate of Orkney 48 



Mr. Alexander Cruickshank's Observations on the Natural Obstructions in 

 the Atmosphere preventing the view of Distant Objects on the Earth's Surface 49 



Mr. T. Davies on the Diurnal Variation of the Barometer 50 



Professor Hennessy on Mild Winters in the British Isles 50 



Mr. J. J. Murphy on the Distribution of Heat over the Sun's Surface 50 



Rear-Admiral FitzRoy on the Aqueous Vapour of the Atmosphere 50 



on Atmospheric Waves 50 



Rev. T. Rankin's Meteorological Observations made at Huggate, Yorkshire ... 52 



M. P. Sandeman on Tables of Rain registered at Georgetown, Demerara 52 



Mr. G. J. Symons on Thunder-storms 54 



Professor W. Thomson on the Reduction of Periodical Variations of Under- 

 ground Temperature, with applications to the Edinburgh Observations 54 



