CONTENTS. vii 



PAGE 



Chapter II. — "Weight of the Air. — Height of the Upper Strata. — Barometric 



Measures 228 



Chapter III. — Mean Pressure of the Atmosphere under various Latitudes. — 

 Density of the Air in the Northern Hemisphere. — Diurnal Oscillations of the 

 Barometrical Column. — Annual Oscillations. — Irregular Variations. — Iso-baro- 

 metric Lines . ^ 232 



Chapter IV. — General Law of the Circulation of "Winds. — Trade-winds from the 

 North-east and South-east. — Equatorial Calms. — Oscillation of the System of 

 Winds 239 



Chapter V. — Counter Trade-winds or Eeturning "Winds 245 



Chapter VI. — The Trade-winds of the Continents. — The Monsoons. — Etesian Winds 253 



Chapter VII. — Land and Sea Breezes. — Winds from the Mountains. — Solar Breezes. 



— Local Winds. — The Simoon, Scirocco, Foehn, Tempests, and Mistral . . 259 



Chapter VIII. — Zone of Variable Winds. — Struggle of Opposing Winds. — Mean 



Direction of the Atmospheric Currents. — Law of Gyration .... 266 



BOOK II.— HURRICANES AND WHIRLWINDS. 



Chapter IX, — Aerial Eddies. — Cyclones of the Equatorial Regions. — The " Great 



Hurricane " 273 



Chapter X. — Speed of the Revolving Masses of Air. — Speed of the Cyclone. — Fall 

 of the Barometric Column. — Irregularities of the Wind in the Path of the 

 Cyclone 280 



Chapter XI. — Spiral of the Hurricanes in the Two Hemispheres. — Theory of Cy- 

 clones. — Nautical Instructions to avoid Hurricanes 287 



Chapter XII. — Eddies of Tempests. — ^Whirlwinds ...... 294 



