v i TABLE OF CONTENT 



METEOROLOGY. 



General Climatology : Peculiarities of different Regions, 50 ; Comparative 

 Climate of Hills and Valleys, 51 ; Unusual Weather in the Arctic Regions 

 in 1871, 51 ; European Winter of 1871-72, 52 ; Relation of Weather to Col- 

 liery Explosions, 53 ; Meteorology of the Future, 68 ; Extension of Ameri- 

 can Weather Telegraphy, 82 ; Atmospheric Electricity, 55 ; Carbonic Acid 

 in the Atmosphere, 97. Atmospheric Pressure and the Winds : Influ- 

 ence on Tides, 41 ; on Colliery Explosions, 53 ; the great Barometric Wave, 

 69 ; Laws of the Winds in Europe, 46 ; Cyclones in the Pacific, 54 ; Unva- 

 rying Course of Cirrus Clouds, 67. Temperatures. Of Land : In South 

 America, 43 ; Change in Northern Hemisphere, 54 ; of Ocean : See Terres- 

 trial Physics. Moisture : Do great Fires produce Rain ? 61 ; Course of 

 Cirrus Clouds, 67. Observations and Instruments: Storm - signals in 

 New South Wales, 44 ; British and American Storm Warnings, 45 ; British 

 Weather Map, 46 ; American Weather Telegraphy, 82 ; Steel Sounding- 

 lines, 56, 62 ; Recording Deep-sea Temperatures, 71. 



C. GENERAL PHYSICS 71 



ELECTRICITY AND MAGNETISM. 



Magnetism. Terrestrial: Adjustment of Ships' Compasses, 71; Variation 

 of the Magnetic Pole, 72 ; new Theory of, 72 ; concurrent Observations, 73 ; 

 General : Action of the Magnet on Electric Light, 74 ; of Diamagnetic 

 Body on Electric Current, 80 ; Magnetism of Petroleum, 81. Electricity. 

 General: Apparatus for recording Deep-sea Temperatures, 71 ; Develop- 

 ment by Friction, 72 ; Electric Pyrometer, 81 ; Weather Telegraphy, 82 ; 

 Atmospheric : Palmieri's Law, 55. Light : Action of the Magnet on Elec- 

 tric, 74 ; Boyden Premium, 75 ; Eliminating Oxygen from Plants, 75 ; 

 Spectroscope, Young on the, 75 ; the Microscope : Nomenclature of Object- 

 ives, 76 ; Refraction of, 76 ; Duration of Visual Impressions, 75 ; Polarizing 

 Action of Tartaric Acid, 79 ; Identification of Lights at Sea, 81 ; of Hydro- 

 gen Flame, 87 ; Action on Olive-oil, 90 ; Chemical Action of Daylight, 90. 

 Heat : Hydrogen Flame, 87 ; Action of Gas Jet on Water, 78 ; Ice Ex- 

 periment, 78 ; Electric Pyrometer, 81. Sound : Transmission in Water, 80. 

 Physics : Change of Volume in Solutions, 100 ; Mensbrugghe's Law, 101 ; 

 Valson's Law, 102. 



D. CHEMISTRY AND METALLURGY 83 



Elementary Bodies. Hydrogen : Phenomena of its Flame, 87 ; Reduci 

 Power when Nascent, 114; Action of Nitric Acid on Metals, 91; Sulphur: 

 Amount in Coal, 86 ; Sulphuric Acid in Vinegar, 103 ; Native Sulphuric 

 Acid in Texas, 114 ; Carhon : Carbonic Acid of the Atmosphere, 97 ; of the 

 Ocean, 58, 59 ; direct Oxydation of, 105. Gold: Friable Coin, 83 ; Silver: 

 Formation of Nitrate from Silver Alloy, 84 ; Iridium : Sensibility to Mer- 

 curial Vapor, 102; Mercury: Relation to Iridium, 102; Nickel: Plating, 

 84; Potassium: Metallic, 84 ; Potash from Corn-cobs, 99 ; Iron: Electric 

 Deposit of, 82 ; Nature of burnt, 85 ; Combustibility of, 109 ; Action with 

 Charcoal on Carbonic Acid, 110 ; Native, in Greenland, 134; from the Iron 

 Sand of New Zealand, 85 ; of California, 133. Reduction of Metals : New 

 Agent for the, 83 ; by Nascent Hydrogen, 114 ; Rivot Process, 86 ; of Iron 



