conte;nts. xxiii 



Wind, 469. — Influence of Salts and Evaporation, 470. — The under Currents 

 owing entirely to the Salts of Sea-water, 471. — A Property ])eculiar to Seas of 

 salt Water, 472. — Quantity of Salt in the Sea, 473. — Deductions, 474. — Drift of 

 the Resolute, 475. — Dc Haven's Drift, 47G. — An anti-polynian View, 477. — Tiic 

 Drift explained, 478. — Thickness of a AVinter's Ice, 47'J. — Layers of Water of 

 difterent Temperature in the Arctic Ocean, 480. — The ice-bearing Drift from 

 the Arctic like the ordinaiy Drift from the Bahic, 481. — Icebergs drifting north, 

 482. — Temperature of the under Current, 483. — It comes to the Surface, 484. — 

 Sea-shells — their Influence upon Currents, 485. — Solid Matter secreted by them, 

 486. — Dynamical Force derived from, 487. — Their physical Relations, 488. — The 

 Regulators of the Sea, 489. — Whence does the Sea derive its Salts? 490. — Their 

 Antiquity, 491. — Insects of the Sea — their Abundance, 492. — Ditto, calcareous 

 in the Pacific, silicious in the Atlantic, 493. — The Records of the Sea and of 

 Revelation agree, 494. — Cubic Miles of Sea-salt, 495. — The Saltness of Water 

 retards Evaporation, 496. — The Harmonies of the Ocean, 497. — The Micro- 

 scope and the Telescope, 498. — Sea-shells and Animalcula? in a new Light, 

 499 Page 234 



CHAPTER XL 



THE CLOUD REGION, THE EQUATORIAL CLOUD-RIXG, AND SEA FOGS. 



Cloud Region— highest in the calm Belts, § 501. — Fogless Regions, 502. — The 

 most stormy Latitudes, 503. — Influences of the Gulf Stream and the ice-bearing 

 Currents of the South, 504. — Sea Fogs rare within 20° of the Equator — Red 

 Fogs, 505. — Cloudless Regions and Height of Clouds at Sea, 506. — Height and 

 Velocity of Waves— Plan for detennining, 507. — Determining the Height of 

 Clouds at Sea, 508. — Cloud Regions at Sea in the Shape of a double-inclined 

 Plane, 509. — Fogs in the Harbor of Callao, 510. — The cloudy Latitudes, 511.— 

 AVhy there should be less xVtmosphere in the southern than in the northern Hemi- 

 sphere, 512. — Influence of antarctic Icebergs in expelling the Air from austral 

 Regions, 513.— The Horse Latitudes— the Doldrums, 514. — A Frigate under the 

 Cloud-ring, 515. — Subjects which at Sea present themselves for Contemplation, 

 516.— The Barometer under the Cloud-ring, 517.— Its Motions, 518.— Meteoro- 

 logical Processes, 519. — Snow-line mounts up as it crosses the Equatorial calm 

 Belt, 520.— Offices of the Cloud-ring, 521.— It acts as a Regulator, 522.— The 

 latent Heat liberated in the Processes of Condensation from and under the Cloud- 

 ring, true Cause of the Trade-winds, 523. — Imagined Appearance of the Cloud- 

 ring to a distant Observer, 524. — Thunder, 525.— Exceeding Interest attached to 

 physical Research at Sea, 526 270 



CHAPTER XII. 



THE GEOLOGICAL AGENCY OF THE WINDS. 



The Sea and Air regarded as Parts of the same Machine, § 531.— The Level of the 

 Dead Sea, 532.— An ancient River from it, 533.— Precipitation and Evaporation 

 in the Dead Sea Valley, 534.— Whence come its Rains? 535.— The Influence 

 of mountain Ranges, 536.— How the Level of Caspians is reduced, 537.— The 

 Formation of inland Basins— a third Process, 538.— Examples, 539.— The Influ- 

 ence of the South American Continent upon the Climate of the Dead Sea, 540.— 

 The Path of the S.E. Trade-winds over into the northern Hemisphere, 541.— Re- 

 lays for supjilying them with Va])or by the way, 542.— Adjustments in tliis Hy- 



