CONTENTS. xyii 



CHAPTEE lY. 



THE ATMOSPHERE. 



Likened to a Machine, § 200.— The Air and the Ocean governed by stable Laws, 201. 

 — Importance of observing the Works of Nature, 202. — Materials for this Chapter, 

 203.— Different Belts of Winds, 204.— The trade-wind Belts, 205.— The return 

 Current, 206. — The Effect of diurnal Rotation on the Course of the Trade-winds, 

 207.— Two grand Systems of Currents, 208.— From the Pole to 35O-30°, 209,— 

 The "Horse Latitudes," 210. — The Barometer there, 211. — The equatorial calm 

 Belt, 212.— The calm Belt of Capricorn, 213. — The polar Calms and the return 

 Current, 214. — Diagram of the Winds — Plate I., 215. — As our knowledge of the 

 LaAvs of Nature has increased, so have our Readings of the Bible improved, 216. — 

 Sloughing off from the counter Trades, 217. — The Air which supplies the south- 

 east Trade-wind in the Band 5° does not cross the Band 25°, 218. — Winds with 

 Northing and Winds with Southing in them contrasted, 219. — South-cast Trade- 

 winds stronger near the equatorial Limits, 220.— Speed of Vessels through the 

 Trade-winds, 221. — The Question. Whence are the south-east Trade-winds supplied 

 with Air? answered, 222. — AVhither it goes, 223. — How it is drawn down from 

 above, 224. — Velocity of south-east shown to be greater than north-east Trade- 

 winds, 225. — The Air sloughed off from the counter Trades moist Air, 226. — The 

 Air sloughed off from the upper Ti'ade Current dry, 227. — The meteorological 

 Influences of ascending Columns of- moist Air, 228. — Supposing the Air visible, 

 the Spectacle that would be presented between the upper and lower Currents, 229. 

 — The Importance of atmospherical Circulation, 230. — Its vertical Movements, how 

 produced, 231. — Vertical and horizontal Movements in the Air Consequents of, 

 and dependent upon each other, 232.— Cold Belts, 233. — The upper Currents, their 

 Numbers and Offices, 234. — Tendency of Air when put in Motion to move in the 

 Plane of a Great Circle, 235. — The Results upon its Circulation of this Tendency, 

 236. — Experiments by the French Academy, 237. — How Supplies of fresh Air are 

 brought down from the upper Sky, 23S. — Beautiful and benign Arrangements, 239. 

 — Their Influences upon the jMind, 240. — The Effect of downward Currents in pro- 

 ducing Cold, 241. — The Winter Northers of Texas, 242.— Their severe Cold, 243. — 

 " Cold Snaps," 244.— Anemometers to determine the Inclination of the wind wanted, 

 245.— The hot Winds of the Andes, 246. — Certain "Hot Spells" explained, 247.— 

 Reservoirs in the Sky, 248. — The warm Winds of the Andes caused by the Trade- 

 Winds, 249.— Dormant Powers of the Telegraph in Meteorologj', 250. — The Wind 

 in his Circuits, 251.~Forces which propel the Wind, 2.52. — Effect of the direct 

 Heat of the Sun upon the Trade-winds, 253. — The two Systems of Trade-winds un- 

 equal both in Force, Duration, and Stability, 254. — Effects of Heat and Vapour, 

 255. — Hurricanes not due to direct Heat of the Sun, 256. — The Influence of other 

 Agents required, 257. — Where found, 258. — Vapour as one of the Causes of the 

 Trade-winds, 259. — Black's Law, 260. — The latent Heat transported in Vapour, 

 261.— The Effect of the Deserts upon the Trade-winds, 262.— Indications of a 

 Crossing at the calm Belts, 263.— The counter Trades — they approach the Pole in 

 Spirals, 264.^They turn ivitli the Hands of a Watch about the south Pole, against 

 them about the north, 265. — The Arrows in the Diagram of the Winds, 266. — The 

 Offices of Sea and Air in the physical Economy, 267. — Powerful Machinery, 

 268 Page 72 



CHAPTER V. 



RAIXS AND RIVERS. 



Rivers considered as Rain-gauges— the ten largest, § 270. — Heat required to lift Va- 

 pour for these Rivers, 271.— Rain-fall in the Mississippi Valley, 272.— Its Area, 

 and the latent Heat liberated during the Process of Condensation there, 273. — 

 Annual Dischai'ge of the Mississippi River, 274.— Physical Adaptations, 275. — 

 Whence come the Rains for the Mississippi, 276. — The north-east Trades of the 

 Atlantic supply Rains only for the Rivers of Central and South America, 277. — 

 The calm Belt of Cancer furnishes little or no Rain, 278.— The North Atlantic 



