Physical Geography Of The Sea 1855

THE PHYSICAL GEOGRAPHY OF THE SEA

1855



BY MATTHEW FONTAINE MAURY, LL.D, LIEUTENANT, UNITED STATES NAVY

THIRD EDITION, ENLARGED AND IMPROVED. NEW YORK: HARPER & BROTHERS, PUBLISHERS, 329 & 331 PEARL STREET, FRANKLIN SQUARE. 1855.

Entered according to act of Congress in the year one thousand eight hundred and fifty five by HARPER & BROTHERS in the clerk’s office of the District Court of the Southern District of New York

AS A TOKEN OF FRIENDSHIP, AND A TRIBUTE TO WORTH, This Volume Is Dedicated To GEORGE MANNING, OF NEW YORK. WASHINGTON OBSERVATORY, December, 1854.

INTRODUCTION

CHAPTER I. — THE GULF STREAM.

The Gulf Stream, § 1. — Its Color, 2. — Its Cause, 3-7. — Franklin’s Theory, 8. The Sargasso Sea, 13. — The Trade wind Agency refuted, 14. — Galvanic Properties of Gulf Stream Waters, 26. — Initial Velocity, 30. — Agents that make Water in one part of the Sea heavier than in another, 31. — Temperature of the Gulf Stream, 37. — It is Roof-shaped, 39. — Why the Drift Matter of the Gulf Stream is sloughed off to the right of its Course, 42. — Course of the Gulf Stream, 47. — Currents run along arcs of Great Circles, 49. — The Course of Currents counter to the Gulf Stream, 52. — The Force derived from Changes of Temperature, 53. — Limits of the Gulf Stream for March and September, 54. — Streaks of Warm and Cool Water in it, 55. — A Cushion of Cold Water between the Bottom of the Sea and the Waters of the Gulf Stream, 56. — It runs up hill, 57.-Page 25

CHAPTER II. — INFLUENCE OF THE GULF STREAM UPON CLIMATES.

An Illustration, § 60. — Best Fish in cold Water, 65. — The Sea a Part of a grand Machine, 67. — Influence of the Gulf Stream upon the Meteorology of the Sea: It is a “Weather Breeder,” 69. — Dampness of Climate of England due to it, 70. — The Pole of Maximum Cold, 71. — Gales of the Gulf Stream, 72. — The Wreck of the San Francisco, 73. — Influence of the Gulf Stream upon Commerce and Navigation: Used as a Landmark, 77. — The first Description of it, 78. — Thermal Navigation, 81.

CHAPTER III. — THE ATMOSPHERE.

The Relation of the Winds to the Physical Geography of the Sea, § 88. — No Expression of Nature without Meaning, 93. — The Circulation of the Atmosphere, Plate I., 95. — Southeast Trade-wind Region the larger, 109. — How the Winds approach the Poles, 112. — The Offices of the Atmosphere, 114. — It is a powerful Machine, 118. Whence come the Rains that feed the great Rivers? 120. — How Vapor passes from one Hemisphere to the other, 123. — Evaporation greatest about Latitude 17 degrees 20 minutes, 127. — Explanation, 128. — The Rainy Seasons: how caused, 129. — Why there is one Rainy Season in California, 130 — One at Panama, 131 — Two at Bogotá, 132. — Rainless Regions explained, 135. — Why Australia is a Dry Country, 136. Why Mountains have a dry and a rainy Side, 137. — The immense Fall of Rain upon the Western Ghauts in India: how caused, 139. — Vapor for the Patagonia Rains comes from the North Pacific, 141. — The mean annual Fall of Rain, 144. Evaporation from the Indian Ocean, 146. — Evidences of Design, 148.

CHAPTER IV. — RED FOGS AND SEA DUST.

Where found, § 157. — Tallies on the Wind, 158. — Where taken up, 160. — Humboldt’s Description, 163.—Information derived from Sea Dust, 165. — Its Bearings upon the Theory of Atmospherical Circulation, 167. — Suggests Magnetic Agency, 170.

CHAPTER V. — ON THE PROBABLE RELATION BETWEEN MAGNETISM AND THE CIRCULATION OF THE ATMOSPHERE.

Reasons for supposing that the Air of the Northeast and of the Southeast Trades cross at the calm Belts, § 174. — What Observations have shown, 184. — Physical Agencies not left to Chance, 188. — Conjectures, 192. — Reasons for supposing that there is a crossing of Trade-wind Air at the Equator, 194. — Why the extra-tropical Regions of the Northern Hemisphere are likened to the Condenser of a Steam boiler in the South, 199. — Illustration, 200. — A Coincidence, 202. — Proof, 203. Nature affords nothing in contradiction to the supposed System of Circulation, 204. Objections answered, 205. — Why the Air brought to the Equator by the Northeast Trades will not readily mix with that brought by the Southeast, 207. — Additional Evidence, 209. — Rains for the Mississippi River are not supplied from the Atlantic, 210. — Traced to the South Pacific, 213. — Anticipation of Light from the Polar Regions, 216. — Received from the Microscope of Ehrenberg, 217, and the Experiments of Faraday, 219. — More Light, 221. — Why there should be a calm Place near each Pole, 222. — Why the Whirlwinds of the North should revolve against the Sun, 223. — Why certain Countries should have scanty Rains, 228. — Magnetism the Agent that causes the Atmospherical Crossings at the calm Places, 231.

CHAPTER VI. — CURRENTS OF THE SEA

Governed by Laws, § 232. — The Inhabitants of the Sea the Creatures of Climate, 233. — The Currents of the Sea an Index to its Climates, 235. — First Principles, 236. — Some Currents run up hill, 237. — Currents of the Red Sea, 238. — Top of that Sea an inclined Plane, 240. — How an under Current from it is generated, 245. — Specific Gravity of Sea Waters, 248. — Why the Red Sea is not salting up, 251. — Mediterranean Currents: How we know there is an under Current from this Sea, 252. — The sunken Wreck which drifted out, 253. — Both Currents caused by the Salts of the Sea, 254. — Currents Of The Indian Ocean: Why immense Volumes of warm Water flow from it, 255. — A Gulf Stream along the Coast of China, 256. — Points of Resemblance between it and the Gulf Stream of the Atlantic, 257. — A Current into Bering’s Strait, 258. — Geographical Features unfavorable to large Icebergs in the North Pacific, 260. — Necessity for cold to restore the Waste by the warm Currents, and Evaporation, 261. — Arguments in favor of return Currents, because Sea Water is salt, 262. — Currents Of The Pacific: Its Sargasso Sea, 264. — The Drift on the Aleutian Islands, 265. The cold China Current, 266. — Humboldt’s Current, 267. — Discovery of an immense Body of warm Water drifting South, 268. — Currents about the Equator, 270. — Under Currents: Experiments of Lieutenants Walsh and Lee, 271. — Proof of under Currents afforded by Deep Sea Soundings, 272. — Currents caused by Changes in Specific Gravity of Sea Water, 273. — Constituents of Sea Water every where the same; affords Evidence of a system of Oceanic Circulation, 274. — Currents Of The Atlantic: The great Equatorial Current: its Fountain-head, 275. — The Cape St. Roque Current proved to be not a constant Current, 276. — Difficulties of understanding all the Currents of the Seashore of the Atlantic can not be accounted for without the aid of under Currents, 277.

CHAPTER VII. — THE OPEN SEA IN THE ARCTIC OCEAN.

How Whales struck on the east Side of the Continent have been taken on the west Side, § 278. — Right Whales can not cross the Equator, 279. — How the Existence of a northwest Passage was proved by the Whales, 280. — Other Evidence in Favor of it, 281. — An under Current sets into the Arctic Ocean, 282. — Evidences of a milder Climate near the Pole, 284. — The Water Sky of Lieutenant De Haven, 285. — This open Sea not permanently in one Place, 286.

CHAPTER VIII. — THE SALTS OF THE SEA.

What the Salt in Sea Water has to do with the Currents in the Ocean, § 289. — Reasons for supposing the Sea to have its system of Circulation, 290. — Arguments furnished by Coral Islands, 293. — What would be the Effect of no system of Circulation for Sea Water? 295. — Its Components, 297. — The principal Agents from which Dynamical Force in the Sea is derived, 300. — Illustration, 302. — Sea and Fresh Water have different Laws of Expansion, 308. — The Gulf Stream could not exist in a Sea of fresh Water, 309. — The effect of Evaporation in producing Currents, 310. — How the Polar Sea is supplied with Salt, 323. — The Influence of this under Current upon open Water in the Frozen Ocean, 326. — Sea Shells: The Influence exerted by them upon Currents, 330. — Order among them, 335. — They assist in regulating Climates, 336. — How Sea Shells and Salts act as Compensations in the Machinery by which Oceanic Circulation is conducted, 339. — Whence come the Salts of the Sea? 344.

CHAPTER IX. — THE EQUATORIAL CLOUD-RING.

Description of the Equatorial Doldrums, § 346. — Oppressive Weather, 348. — The Offices performed by Clouds in the terrestrial Economy, 349. — The Barometer and Thermometer under the Cloud-ring, 350. — Its Offices, 353. — How its Vapors are brought by the Trade-winds, 361. — Breadth of the Cloud-ring, 363. — How it would appear if seen from one of the Planets, 364. — Observations at Sea interesting, 368.

CHAPTER X. — ON THE GEOLOGICAL AGENCY OF THE WINDS.

To appreciate the Offices of the Winds and Waves, Nature must be regarded as a Whole, § 369. — Level of the Dead Sea, 370. — Evidences that at former Geological Periods more Rain fell than now falls upon the Dead Sea and other inland Basins, 371. — Where Vapor for the Rains in the Basin of the American Lakes comes from, 375. — The Effect produced by the Upheaval of Mountains across the course of vapor-bearing Winds, 376. — The Agencies by which the Drainage of Hydrographic Basins may be cut off from the Sea, 380. — Utah an Example, 382. — Effect of the Andes upon vapor-bearing Winds, 383. — Geological Age of the Andes and Dead Sea compared, 391. — Ranges of dry Countries and little Rain, 393. — Rain and Evaporation in the Mediterranean, 399. —Evaporation and Precipitation in the Caspian Sea equal, 404. — The Quantity of Moisture the Atmosphere keeps in Circulation, 407. — Where Vapor for the Rains that feed the Nile come from, 409. — Lake Titicaca, 420.

CHAPTER XI. — THE DEPTHS OF THE OCEAN.

The Depth of blue Water unknown, § 421. — Results of former Methods of Deep-sea Soundings not entitled to Confidence, 422. — Attempts by Sound and Pressure, 423. — The Myths of the Sea, 424. — Common Opinion as to its Depths, 425. — Interesting Subject, 427. — The deepest Soundings reported, 428. — Plan adopted in the American Navy, 429. — Soundings to be made from a Boat, 431. — Why the Sounding twine will not stop running out when the Plummet reaches Bottom, 432. — Indications of under Currents, 433. — Rate of Descent, 434. — Lieutenant John Mercer Brooke’s Deep-sea Sounding Apparatus, 437. — The greatest Depths at which Bottom has been found, 438.

CHAPTER XII. — THE BASIN OF THE ATLANTIC.

Plate XI., § 439. — Height of Chimborazo above the Bottom of the Sea, 440. — Orography of Oceanic Basins, 441. — The deepest Place in the Atlantic, 442. — THE BOTTOM OF THE ATLANTIC: The Utility of Deep-sea Soundings, 445. — A Telegraphic Plateau across the Atlantic, 446. — Specimens from it, 447. — A microscopic Examination of them, 448. — Brooke’s Deep-sea Lead presents the Sea in a new Light, 453. — The Agents at work upon the Bottom of the Sea, 454. — How the Ocean is prevented from growing salter, 458. — Knowledge of our Planet to be derived from the Bottom of the Sea, 460.

CHAPTER XIII. — THE WINDS.

Plate VIII., § 461. — Monsoons, 462. — Why the Belt of Southeast is broader than the Belt of Northeast Trade-winds, 463. — Effect of Deserts upon the Trade-winds, 466. — At Sea the Laws of Atmospherical Circulation are better developed, 470. — RAIN WINDS: Precipitation on Land greater than Evaporation, 472. — The Place of Supply for the Vapors that feed the Amazon with Rains, 473. — MONSOONS: How formed, 474. — Monsoons of the Indian Ocean, 475. — How caused, 476. — How the Monsoon Season may be known, 478. — The Distance to which the Influence of Deserts upon Winds may be felt at Sea, 479. — Why there are no Monsoons in the Southern Hemisphere, 482. — Why the Trade-wind Zones are not stationary, 483. THE CALM BELTS: Doldrums — a Zone of constant Precipitation, 486. — The Horse Latitudes, 488. — The Westerly Winds, 490.

CHAPTER XIV. — THE CLIMATES OF THE OCEAN.

Gulf Stream likened to the Milky Way, — 492. — March and September the hottest Months in the Sea, 496. — How the Isothermal Lines move up and down the Ocean, 498. — A Line of invariable Temperature, 508. — How the western Half of the Atlantic is heated up, 509. — The Relation between a Shore-line in one part of the World and Climates in another, 512. — The Climate of Patagonia, 516. — The Summer of the northern Hemisphere warmer than the Summer of the southern, indicated by the Sea, 521. — How the cold Waters from Davis’s Straits press upon the Gulf Stream, 522. — How the different Isotherms travel from North to South with the Seasons, 523. — The Polar and Equatorial Drift, 524.

CHAPTER XV. — THE DRIFT OF THE SEA.

Object of Plate IX., § 528. — The Eastern Edge of the Gulf Stream sometimes visible, 529. — The Polar Drift about Cape Horn, 533. — How the Polar Waters drift into the South Atlantic, and force the Equatorial aside, 535. — How this is accomplished, 537. — A Harbor in a Bend of the Gulf Stream for Icebergs, 539. — Why Icebergs are not found in the North Pacific, 540. — The Womb of the Sea, 541. — Drift of warm Waters out of the Indian Ocean, 543. — A Suggestion from Lieutenant Jansen, of the Dutch Navy, 544. — A Current of warm Water sixteen hundred Miles wide, 545. — The Pulse of the Sea, 546. — How the Gulf Stream beats Time, 547. — The Circulation of the Sea likened to that of the Blood, 548. — THE FISH: Number of Vessels engaged in the Fisheries of the Sea, 551. — The Sperm Whale delights in warm Water, 552. — The Torrid Zone impassable to the Right Whale, 553.

CHAPTER XVI. — STORMS.

Typhoons, § 559. — Cyclones, 561. — West India Hurricanes, 562. — Extra-tropical Gales, 563. — The San Francisco’s Gale, 564. — These Gales seldom occur at certain Seasons, 565. — Most prevalent Quarter for the Gales beyond the Calm Belt of Caprieorn, 566. — Storm and Rain Charts, 567.

CHAPTER XVII. — ROUTES.

How Passages have been shortened, § 568. — How closely Vessels follow each other’s Track, 570. — The Archer and the Flying Cloud, 571. — The great Race-course upon the Ocean, 573. — Description of a Race, 575. — Present Knowledge of Winds enables the Navigator to compute his Detour, 582.

CHAPTER XVIII. — A LAST WORD.

Brussels Conference, § 584. — How Navigators may obtain a Set of Lieutenant M. F. Maury’s “Wind and Current Charts”, 585. — The Abstract Log, 586.