CONTENTS. V 



Page 

 Dr. W. J. Macquobn Rankine's Investigation of the Mathematical Theory 



of Comhined Streams 18 



__ on the Thermodynamic Acceleration and 



Retardation of Streams 18 



Mr. John T. Towson's Report of the Liverpool Compass Committee 19 



Mr. W. Pabkes on Non-tidal Variations of the Sea-level on the Coast of 

 India 19 



Astronomy. 



Mr. W. R. BiRT on the Present State of the Question relative to Lunar Ac- 

 tivity or Quiescence 20 



Mr. A. S. Dayis on the Distribution of Cometic Perihelia 22 



The Rev. Fredemck Howlett on Solar Spots observed during the past 



Eleven Years 23 



The Rev. R. Main on Shooting-stars 24 



Mr. R. A. Pboctor on the Laws of Star-grouping 24 



Electeicitt and Magnetism. 



Mr. C. Beckeb on Faure's Battery 24 



Mr. John Bbowning on an Induction-coil, specially arranged for use in Spec- 

 trum Analysis 25 



Mr. H. HiGHTON on the Maximum amovmt of Magnetic Power which can be 

 developed by a given Galvanic Battery 25 



Dr. Joule's Letter on a New Dip-Circle 2-5 



Mr. W. Ladd on an Improved Lantern for Lecture demonstrations with Elec- 

 tric Light 26 



Professor Sir William Thomson on a New Absolute Electrometer 2(3 



Mr. Fbedebick H. Vabley on a New Field of Magnetic Research 26 



on a Constant Battery 26 



Mr. S. Alfred Vabley on a Magnetic Paradox 27 



's Description of the Electric Time-Signal at Port 



Elizabeth, Cape of Good Hope 27 



on the Mode of .i^ction of Lightning on Telegraphs, 



and on a New Method of constructing Telegraph-coils 28 



Meteohologt. 



Mr. Chakles Chambers on Rainfall — its Variation with Elevation of the 



Gauge 30 



Professor J. D. Eveeett on a Scale for computing Humidity 31 



Mr. Fbancis Galton on Barometric Predictions of Weather 31 



Mr. James Glaisheb on the Temperature of the Air at 4 feet, 22 feet, and 

 50 feet above the Ground 33 



Mr. John J. Hall on a New Electro-Magnetic Anemometer, and the mode 

 of using it in Registering the Velocity and Pressure of the Wind 35 



Professor J. Henby on the Rainfall of the United States 36 



Heat, Light. 

 Mr. Charles Brooke's Queries respecting ^Ether , 36 



