Chapter XL: Appendix (4)
Pacific Ocean, islands of, 140;
volcanic islands in, 148;
great volcanic zone in, 149;
areas of elevation and subsidence in its bed, _ib._;
its size, 189.
Palapteryx, fossil bird, 411.
Palms, distribution of, 333.
Palte, lake of, 249.
Pamer, table-land, 420.
Pampas of Buenos Ayres, 106;
their elevation, _ib._;
floods, 107;
conflagrations, _ib._;
geology, 113.
Pampéros hurricanes, 271.
Panama, plains of, extent, 115.
Pandanus, genus of plants, 144.
Pangolin, or manis, 421.
Panicum, genus of Cerealia, 356.
Panthers, 421.
Paradise, birds of, 402.
Parima, mountain system of, 103;
Sierra del Parima, _ib._;
musical rock in, _ib._
Parry, Sir Edward, 464.
Parry’s Mountains, 166.
Passages across the Atlantic, 267.
Patagonia, desert of, 106;
climate, _ib._;
geology, 113.
Peccari, or South American hog, 428.
Pelasgic Islands, description of, 140.
Peltier’s experiments on the heat of the earth, 255.
Pendulum, 17;
its oscillations influenced by gravitation, _ib._;
variations in, 18;
experiments with, for ascertaining compression at the poles, 17;
affected by volcanic islands, _ib._
Penguins, southern (Aptenodytes), 408.
Peninsulas, their southward tendency, 40;
form, _ib._
Pentland, Mr. his measurements of Cordilleras and mountains of the
Andes, 97, _note_;
and of their passes, 101, _note_;
his discovery of a volcanic crater in the valley of the Yucay, 109,
_note_;
and of fossil shells in Bolivia and Peru, 112, _note_;
on measurement of highest peaks and mean heights of several
mountain-chains, 135, _note_;
on horary variation of the barometer, 265;
on fishes of Lake of Titicaca, 375;
on the naturalization of the Llama tribe, 431.
Pepper-tree, 325.
Perfume of flowers, cause of, 304.
Persia, table-land of (Plateau of Iran), area and elevation of, 55;
extent of Persian mountains, 57;
great salt desert, 58;
flora, 319.
Petra, appearance of its site, 83.
Petrel, stormy, the, 397.
Petrel, genus, or Procellariæ, 397, 408.
Phacochœre, or African hog, 425.
Phalanger, 434.
Pheasants, different species of, 401.
Philedon, genus of birds, 401.
Phocæ, or seals, 377.
Physalia, 376.
Physeters, or cachalots, 379.
Pichincha, height of, 100.
Planets, their magnitude relative to that of the earth, 15;
their influence on the earth’s motion, _ib._
Plants, division of, 306;
propagation of, 305;
sleep of, _ib._;
nourishment of, 300; elements of, 301;
geographical distribution of, 306.
Pleiocene period, the earth and its inhabitants during, 30;
changes during, 31;
discoveries of perfect animals buried in this period, 32.
Pœppig, Dr., his ‘Travels’ quoted, 94, 176;
on red water of the ocean, 370.
Pole, North, reasons for the existence of sea at, 203.
Poles, compression at, ascertained by perturbations in the moon’s
motions, 15;
by oscillations of the pendulum, 17.
Polynesia, flora of, 401.
Polyplectron, genus of birds, 407.
Pontoppidan, or sea-serpent, 381.
Popocatepetl, mountain, 121.
Porcupine, 417.
Porpoise, genus of, 379.
Porter, G. R., Esq., his ‘Progress of the Nation’ quoted, 184, _note_.
Porto Rico, dimensions and climate, 117.
Portugal, flora of, 319.
Potato, country of, 350.
Potosi, the height of, 97, _note_;
city of, its elevation, 97;
its mines, 175.
Prairies, N. American, 127, _note_.
Prairie-dog, a marmot, 427.
Prairie wolf, 427.
Prongbuck antelope, 427.
Prongos, 315.
Proteus anguinus, 386.
Puma, or American lion, 428.
Punjab, 80.
Pyrenees, flora of, 318.
Python, genus of snakes, 388.
Q.
Quadrumana, or monkeys, 413.
Quadrupeds, European, 416;
Asiatic, 417;
African, 423;
American, 426;
Australian, 433.
Quagga, species of horse, 424.
Quebec, summer of, 260.
Quicksilver, diffusion of, 178.
Quito, valley of, 99;
dimensions, _ib._;
city of Quito, 100;
monuments of the Incas, _ib._
Quotlamba mountains, 87.
R.
Races of mankind, 436;
inhabiting Europe, 441.
Racoon, 427.
Radii of the earth measured by M. Bessel, 16.
Rakastal lake, 249.
Rain, cause of, and distribution, 275.
Rains, periodical, 275;
countries without, 278.
Rainbows, 283.
Rattle-snakes, 387.
Realejo Bay, 252.
Redfield, W. C., on storms, 270, _note_.
Reich, M., mean density of the earth as ascertained by the torsion
balance, 19, _note_.
Reid, Colonel, on storms, 270.
Rein-deer Lake, 252.
Reptiles, classification of, 383;
geographical distribution of, 385.
Rhinoceros of Asia, 422;
of Java, _ib._;
of Africa, 424.
Rhyncops, or scissor-bill bird, 408.
Rice, cultivation of, 356.
Richardson, Dr. Sir J., his account of the fauna of North America
quoted, 131, 464.
Rivers, origin of, 212; course of, _ib._;
velocity, 213;
junction of rivers, _ib._;
influence of wind and frost, 214;
deltas, _ib._;
tides, _ib._;
floods, _ib._;
inundations, 215;
heads of rivers, _ib._
Rocks, their division into four classes, 19;
plutonic rocks, _ib._;
volcanic rocks, 20;
metamorphic rocks, _ib._;
aqueous rocks, 21;
pierced by lava, _ib._;
Sir Charles Lyell’s theory concerning, 20;
forms of, 42;
height of calcareous rocks in the Alps, 53.
Rocky Mountains, 122.
Rodentia, or gnawers, 414;
American, 432.
Rogers, H. D., Esq., his ‘Physical Geography of North America’ quoted,
130.
Rorqual, a species of whale, 381.
Ross, Sir James, his account of a gale, 205, 464.
Ruminating animals, 413.
Russell, J. Scott, Esq., his ‘Theory of Waves’ quoted, 195, _note_.
Rye, cultivation of, 356.
S.
Sabine, Colonel, experiments with the pendulum, 18, and _note_;
mean height of the Himalaya, 61;
on terrestrial magnetism, 294, 464.
Saquis, bush-tailed monkeys, 429.
Sahama, trachytic dome of, its height, 111.
Sahara desert, 90.
Salamanders, 386.
Salt, diffusion of, 186.
Samojedes, 442.
Sanders-wood, 327.
Sandwich Land, vegetation, 351.
Santa Martha, group of, 100.
Saratov, 248.
Saurians, order of, 389.
Saussure, Necker, on direction of stratified masses, 295.
Solimaun chain, 59.
Scandinavian mountain system, 69;
extent and elevation, 70;
part of the same system as those of Feroe, Britain, Ireland, and
northeastern Ireland, _ib._
Schomburgk, Sir Robert, on water-communication in South America, 243.
Schools, ragged, 473.
Sclavonian races, 441.
Scorpions, 366.
Scotland, its mountains, 71;
direction of, _ib._;
table-land, height of, _ib._;
lakes, _ib._;
earthquakes, 154;
coal-measures, 183.
Scythrops, genus of birds, 409.
Sea, its mean depth, 17;
rise and fall of, after an earthquake, 155.
Sea, Alps of North America, 122.
Sea serpents, pretended, 282.
Sea snakes, 387.
Secretary-bird, the, 402.
Sedgwick, Mr., mountains of Westmoreland, 44.
Seed, mode of development, 300.
Serpents, or ophidians, 386;
venomous, _ib._;
innocuous, 388;
tree, _ib._
Shahee Lake, 248.
Siberia, its area, 75;
mineral riches, _ib._;
soil, _ib._;
climate, _ib._;
flora, 314.
Sicily, plants of, 319.
Sierra do Mar, 104.
Sierra dos Vertentes, 105.
Sierra Madre, 122.
Silk-worms, 366.
Silvas of the Amazons, 107;
dense vegetation, _ib._;
area of woodland, _ib._;
Humboldt’s description of, _ib._;
geology of, 114.
Silver, diffusion of, 175.
Simayang, a species of ape, 422.
Sinai, Mount (Jebel Houra), its height, 82;
group of Sinai, _ib._
Sine of the latitude, 17, _note_.
Sir-i-Kol, lake of, 249.
Skaptar Jokull, eruption of, in 1783, 161.
Skink, a species of lizard, 390.
Skua gull, 396.
Slave-lake, 252.
Slave-trade, its evil effects, 459.
Sleet, nature of, 283.
Smyth, Captain, R. N., report of soundings, 46, _note_.
Snae Braen, area of, 70.
Snow, how produced, 278;
form of its crystals, 279.
Snow-line, its height on mountains in different latitudes, 279.
Solar system, 15, _note_.
Soudan, 251.
South magnetic pole, its situation, 166.
Senegambia, 89.
South Shetland, vegetation, 352.
South Wales, New character of the country, 137;
structure, 139.
Spain, its mountains, 47;
table-land, area of, _ib._;
plants of, 319.
Spiders, numbers of, 367.
Spitzbergen, 160.
Springs, their origin, 209;
intermittent, 210;
temperature, 211;
hot springs, _ib._;
medicinal springs, _ib._;
saline springs, _ib._
Squalls, arched, 271.
Squirrels, flying, 422.
Steam-power, amount of, in Great Britain in 1833, 172, _note_.
St. Elias, Mount, height of, 123.
Stelvio, pass of, its height, 50.
Steppes of Eastern Europe, 74;
great extent of, _ib._;
climate, _ib._;
soil, _ib._;
atmosphere, 75.
St. Lawrence, river, 12.
Stonefield slate, 26.
Storms, rotatory, 268;
waves, 270.
Strata, primary fossiliferous, 21;
Cambrian, 21;
lower Silurian, _ib._;
upper Silurian, 22;
secondary fossiliferous, _ib._;
Devonian, _ib._;
carboniferous, 23;
mountain limestone, _ib._;
magnesian limestone, 24;
new red sandstone, 25;
oolite, _ib._;
cretaceous strata, 27;
tertiary strata, divided by Sir Charles Lyell into Eocene, Miocene,
and Pleiocene, 28;
boulder formation, 32;
parallel direction of contemporary strata, 43.
Strata, tertiary, of the Alps, height of, 53.
Strachey, Lieut., journeys, 17.
Sudetes, the, 48.
Suez, projected canal of, 461.
Sulphur, diffusion of, 186.
Sumatra, character of the island, 150.
Sumbawa, population of, 438.
Summa Paz, Sierra de la, 100.
Sun, his mass, 15.
Superior, Lake, 251.
Symonds, Major A., on the depression of the Dead Sea, 84, _note_.
Syren, genus of reptiles, 386.
Syria, its soil, 84;
deterioration of the country, _ib._;
shrinking of the strata, _ib._
Swamps, area of, in Denmark, 74.
T.
Table-lands, their soil and climate, 45.
Table Mountain (Cape Town), its height, 86.
Tangaras, American birds, 406.
Tapir, Indian or Malayan, 419;
American, 414.
Targatabai, volcanic range of, 152.
Tartary, flora of, 321.
Tariyani, tract of, 60.
Taurus mountains, 296.
Taylor, Mr., description of an ice-storm in Canada, 127.
Taylor, John, Esq., on the Cornish mines, 172, _note_.
Tchad, river and lake, 251.
Tea, cultivation and varieties of, 321.
Tehuantepec, isthmus of, 116, 252;
bay, _ib._
Temperature of the ocean, 201;
stratum of constant temperature, 202;
line of maximum temperature, _ib._
Temperature of the earth, 254;
mean at any place, 257;
highest observed, 258.
Terror, Mount, 166.
Teutonic races, 442.
Thean-Tchan, volcanic chain of, 152.
Thian-shan, or Celestial Mountains, 59, _etc._
Thomas, St., island, 269.
Thunder storms, 286;
causes of, 287.
Tiberias, Lake, 247.
Tibet, table-land of (Oriental plateau), its area and altitude, 55;
its form and situation, 58;
its width, 69;
mean height, 134.
Tibet, flora of, 316.
Tides, influence of the sun and moon upon, 191;
spring tides, 192;
neap-tides, _ib._;
frequency of tides, _ib._;
their succession, _ib._;
marginal tide, _ib._;
heights of tides, 193;
variation in, _ib._;
velocity, _ib._;
stream, 194.
Tierra del Fuego, account of, 94, 105;
geology, 113;
flora of, 352.
Tiger, royal, country of, 421.
Tin, diffusion of, 178.
Tinamous, an American bird, 407.
Titicaca, lake of, 97;
area and height, 253.
Toads, 384.
Tobolsk, elevation of, 134.
Tomboro, volcanic eruption of, in 1815, 150.
Toozla Lake, 248.
Tortoises, 391.
Trade-winds, 265.
Tragopons, an East Indian bird, 401.
Trees, growth of, 357;
age of, _ib._
Trigonocephalus, or yellow ape, 387.
Tripe de Roche, 314.
Tristan d’Acunha, island, 282.
Trogon, 401.
Troupials, 406.
Trüb, lake of, 247.
Trionyx, 391.
Tui, a New Zealand bird, 412.
Tnngut, or Chinese Tartary, its geographical position, 60.
Turks, 442.
Turtles, 392.
Tuscany, earthquakes in, 154.
Tussack grass, 353.
U.
Uleaborg, 275.
Ular, lake, 249.
Unau sloth, the, 429.
United States territory, area of, 130.
Ural Mountains, 72; extent, _ib._;
height, _ib._;
mineral riches, _ib._;
geology, 73.
Urmiah Lake, 248.
V.
Valmiki, author of the Ramayana, 439, _note_.
“Valley of Death,” 153.
Vampire-bats, 420.
Van, lake, 57, 248.
Van Dieman’s Land, area of, 138;
mountains, _ib._;
soil, _ib._;
structure, 139;
flora, 337.
Vanessa Cardui, a butterfly, 364.
Vanilla Epidendron, 345.
Variables, the, 265.
Vegetation, mode of, 298;
effects of, on the atmosphere, 299.
Veragua, Cordillera of, its height, 115.
Verneuil, M. de, 67, _note_.
Vermejo river, 349.
Victoria Land, 165; ice cliffs, _ib._;
mountains, _ib._;
its appearance described, _ib._
Vicuña, 430;
its naturalization, _ib._
Vipers, 387.
Vultures, European, 398;
American, 404.
Volcanic eruptions, frequency of, 153.
Volcanic islands, 148.
Volcanos, eruptions of, 20;
active volcanos, 152.
W.
Wales, earthquakes in, 154.
Waves, causes of, 144;
height, 195;
ground-swell, _ib._;
billows, _ib._;
surf, 196;
force of waves, _ib._
Wealden clay, 27.
Weddell, Dr., on Cinchona, 347, _note_;
on breed of alpaca and vicuna, 431.
Werner, law of parallelism of mineral veins, 43.
Western Asia, its table-lands and mountains, 55.
West Indian islands, 116;
Lesser Antillas (group), _ib._;
Greater Antillas, 117;
Bahamas, 118;
structure, _ib._
Whales, 380.
Wheat, varieties and cultivation, 355.
Whirlwinds, 271.
[Wilkes, Capt. C., discovery of Antarctic Continent, 167.]
Winds, theory of, 264;
trade, 265.
Winnipeg Lake, 252.
Wombat, 434.
Wrangel, Admiral, on the climate of Siberia, 76;
his attempt to reach the North Pole, _ib._, _note_.
X.
Xarayos Lake, 252.
Y.
Yablonnoi Khrebet, 66.
Yablonnoi Mountains, 296.
Yakutsk, “the coldest town on the earth,” 77, 260.
Ybera, swamp, its area, 107.
Yenesei, flora of, 316.
Z.
Zambeze, lake, Africa, 250.
Zealand, New, its mountains, 141;
coast, _ib._;
general character, _ib._
Zebra, 424.
Zenes, their breadth, 16.
Zungary, or Mingolia, its situation, 60.
Zurrah, lake, 248.
Footnotes
Footnote 1:
“Cosmos,” by Alexander Von Humboldt, translated under the
superintendence of Colonel E. Sabine, F.R.S. Second Edition. London,
1848.
Footnote 2:
Alexander Keith Johnston’s “Physical Atlas,” 4to., in Monthly Numbers.
Edinburgh, 1849. [Published by Lea & Blanchard, Philadelphia, 1850.]
Footnote 3:
The Solar System:—
Mercury, nearest the Sun, known to the ancients.
Venus, known to the ancients.
The Earth.
Mars, known to the ancients.
Flora, discovered by Mr. Hind in 1847.
Vesta, discovered by Mr. Olbers in 1807.
Iris, discovered by Mr. Hind in 1847.
Metis, discovered by Mr. Graham in 1848.
Hebe, discovered by Mr. Hencke in 1847.
Astræa, discovered by Mr. Hencke in 1845.
Juno, discovered by Mr. Harding in 1804.
Ceres, discovered by M. Piazza in 1801.
Pallas, discovered by Mr. Olbers in 1802.
Jupiter, known to the ancients.
Saturn, known to the ancients.
Uranus, discovered by Sir William Herschel in 1781.
Neptune, discovered by M. Le Verrier and Mr. Adams in 1846.
Footnote 4:
The compression of the earth is the flattening at the poles. Its
numerical value is equal to the difference between the equatorial and
polar diameters, expressed in feet or miles. [The amount of
compression, oblateness at the poles, is measured by the ratio of the
difference of the equatorial and polar diameters to the equatorial
diameter, which is technically termed the _oblateness_. The following
are the dimensions of the earth in miles:
Miles. Diameter. Radius at the equator 3962·6 = 7925·2 Radius at the pole 3949·6 = 7899·2 Difference of equatorial and polar radii 13·0 = 26·0 Mean radius, or at 45° Latitude 3956·1 = 7912·2 Mean length of a degree 69·05 —— The fourth part of a meridian 6214·2 ——]
Footnote 5:
The theoretical investigation of the figure of the earth, the method
employed for measuring arcs of the meridian, and that of finding the
form of the earth from the oscillations of the pendulum, are given in
the “Connection of the Physical Sciences,” by Mary Somerville, 7th
Section, 7th edition.
Footnote 6:
A pendulum which oscillates 86,400 times in a mean day at the equator,
will do the same at every point of the earth’s surface if its length
be increased progressively to the pole as the square of the sine of
the latitude. The sine of the latitude is a perpendicular line drawn
from any point of a terrestrial meridian to the equatorial radius of
the earth. That line expressed in feet or miles, and multiplied by
itself, is the square of the sine of the latitude. Gravitation
increases from the equator to the poles according to that law, and the
length of the degrees augments very nearly in the same ratio.
Footnote 7:
The compression deduced by M. Bessel from arcs of the meridian is
1/299; that deduced by Colonel Sabine from his experiment with the
pendulum is 1/288·7. Other pendulum experiments have given a
compression of 1/298·2 and 1/266·4. The protuberant matter at the
earth’s equator produces inequalities in the moon’s motions, from
whence the compression of the earth is found to be 1/305·05; and
although the reciprocal action of the moon on the protuberant matter
at the earth’s equator does not actually give the compression, it
proves that it must be between 1/279 and 1/573. Coincidences so near
and so remarkable, arising from such different methods, show how
nearly the irregular figure of the earth has been determined. The
inequalities in the motions of the moon and earth alluded to are
explained in Sections 5 and 11 “Connection of the Physical Sciences.”
Footnote 8:
It is clear that the mean density of the earth may be found from the
attraction of the plumb-line by mountains, or by the irregularity in
the oscillations of the pendulum, but the torsion balance is a much
more sensible instrument than either. The density determined by M.
Reich differs from that found by Mr. Baily by only one twenty-eighth
part.
Footnote 9:
If a line be drawn from the north-eastern coast of North America
within the limit of floating ice, and if it be continued across the
southern half of Ireland and England, and prolonged eastward so as to
strike against the Ural mountains, it will mark the boundary of the
European portion of the Glacial Sea. It submerged part of Russia to
the depth of 1000 feet.—Essay on the British Fauna and Flora, by
Professor E. Forbes, in the “Memoirs of the Geological Survey of Great
Britain,” vol. i.
Footnote 10:
Sir James Ross and Captain Wilkes met with icebergs covered with mud
and stones in the antarctic seas, and even in 66° 5ʹ lat. One block
seen by Sir James Ross was estimated to weigh many tons.—Antarctic
Voyages.—[Narrative of United States Exploring Expedition. By Charles
Wilkes, U. S. N.].
Footnote 11:
Account of the Ganges and Brahmapootra, by Major Rennell.—“Phil.
Trans.,” 1781. Sir George Staunton’s Embassy to China. Elie de
Beaumont, Leçons de Géologie, 1 vol., 8vo. The latter work contains a
very elaborate essay on alluvial deposits by rivers, &c.
Footnote 12:
Lieut. Anjou’s Polar Voyage.
Footnote 13:
[See Statistics of Coal. By Richard Cowling Taylor. Philadelphia,
1848.]
Footnote 14:
The author’s geological information rests on the authority of those
distinguished authors whose works are in the hands of every one,
namely, Baron Cuvier, Sir Charles Lyell, Sir Roderick Murchison, Sir
Henry de la Beche, Professor Owen, and the Memoirs of the Geological
Society.
Footnote 15:
The proportions of land to water referred to in the text were
estimated by Mr. Gardner. According to his computation, the extent of
land is about 37,673,000 square British miles, independently of
Victoria Continent [discovered by Charles Wilkes, U. S. N.]; and the
sea occupies 110,849,000. Hence, the land is to the sea as 1 to 4
nearly. The unexplored region within the Arctic Circle is about
7,620,000 square miles.
Footnote 16:
This very general view of the structure of the globe originated
chiefly with the celebrated German geologist Von Buch, and has been
much extended and developed by M. Elie de Beaumont, one of the most
philosophical of modern geologists.
Footnote 17:
M. Boué.
Footnote 18:
The author avails herself with much pleasure of an opportunity of
expressing her admiration of the accuracy, extent, and execution of
Mr. Keith Johnston’s Physical Atlas, and of the valuable information
contained in the letterpress which accompanies it, which has afforded
her the greatest assistance. As Mr. Johnston is publishing a small and
cheap edition of his Atlas, well fitted to illustrate these volumes,
the necessity of inserting in them any similar maps, which was at one
time contemplated, is obviated.
Footnote 19:
“On the Parallel Lines of Simultaneous Elevation in the Weald of Kent
and Sussex,” by —— Hopkins, Esq.
Footnote 20:
M. Boué.
Footnote 21:
By the soundings of Captain Smyth, R. N., the Strait is 960 fathoms
deep between Gibraltar and Ceuta, and varying from 160 to 500 in the
narrowest part.
Footnote 22:
A crater of elevation is a mountain, generally dome-shaped, whose top
has sunk into a crater or hollow, after the internal force which
raised it was withdrawn, but from which no lava has issued.
Dome-shaped mountains owe their form to internal pressure, probably
from lava, but which have not sunk into a crater.
Footnote 23:
Professor Forbes on Glaciers.
Footnote 24:
Dr. Boué.
Footnote 25:
Sir Charles Lyell.
Footnote 26:
Johnston’s Physical Atlas.
Footnote 27:
Sir John Malcolm on Persia, and Mr. Morier’s Travels.
Footnote 28:
Johnston’s Physical Atlas.
Footnote 29:
Ibid.
Footnote 30:
Johnston’s Physical Atlas.
Footnote 31:
Sir Roderick I. Murchison.
Footnote 32:
From the observations of Sir Roderick Murchison, M. Middendorf, M. de
Verneuil, and Count Keyserling, it appears also that the low land of
Siberia has been extended since the existing species of shell-fish
inhabited the northern seas; a circumstance that must have rendered
the Siberian climate still more severe, and materially affected that
of the northern parts of Europe and Asia.
Footnote 33:
In 1820, Admiral (then Lieutenant) Wrangel travelled from the mouth of
the Kolyma to Behring’s Straits on sledges drawn by dogs, and made a
bold but vain attempt to reach the North pole. Lieutenant Anjou, at
the same time, sailed from the mouth of the Jana river, reached 76-1/2
degrees of north latitude, and passed round the group of the New
Siberian Islands.
Footnote 34:
Johnston’s Physical Atlas.
Footnote 35:
From Miss Martineau’s spirited and picturesque account of her journey
to Egypt and Syria.
Footnote 36:
By the trigonometrical measurement of Major Anthony Symonds, confirmed
by French authorities, and adopted by Baron Humboldt, the depression
of the Dead Sea is, as stated in the text, 1300 feet; but MM. Bertou
and Russiger made it out to be 1388 by the barometer. See Lieut.
Molyneux’s paper in the Journal of the Royal Geographical Society,
1848.
Footnote 37:
[For a very interesting and reliable account of the river Jordan and
its valley, the reader is directed to a “Narrative of the United
States’ Expedition to the River Jordan and the Dead Sea, by W. F.
Lynch, U. S. N., Commander of the Expedition.” Philadelphia, 1849.]
Footnote 38:
Estimated from N.E. to S.W., the proportion of the two slopes of the
Abyssinian table-land is as 12·6 to 1.
Footnote 39:
Johnston’s Physical Atlas.
Footnote 40:
The Voyage of Captain King, R. N., Mr. Darwin’s “Journal of a
Naturalist,” Dr. Pœppig’s “Travels in South America,” are the
authorities for the account of Tierra del Fuego, Patagonia, and Chile;
Baron Humboldt, Mr. Pentland, Drs. Pœppig and Meyer of Berlin, for
Peru and the Andean Chain to the Isthmus of Panamá.
Footnote 41:
This great height has been deduced, adopting the position of the Peak
as fixed by Captain Fitz Roy, and employing the angles of elevation
observed by Captain Beechey near Valparaiso.
Footnote 42:
Dr. Pœppig’s Travels.
Footnote 43:
The celebrated silver mines of Potosi were formerly worked to the very
summit of that metalliferous mountain, 16,150 feet above the sea
level.
Footnote 44:
Baron Humboldt and Mr. Pentland.
Footnote 45:
The breadth of the table-land, and the two Cordilleras of the Bolivian
Andes given in the text, was measured by Mr. Pentland; he also
determined the heights of Illimani to be 21,150 feet; of Supäíwasi or
Huayna Potosi, 20,260 feet; and of Ancohuma or the Nevado of Sorata,
21,290 feet.
Footnote 46:
Baron Humboldt.
Footnote 47:
Baron Humboldt.
Footnote 48:
It appears by the measurements of Mr. Pentland in the Peru-Bolivian
Andes, that many of their passes are higher than in the equatorial
portion of the chain. The passes of Rumihuasi, on the high road from
Cusco to Arequipa, of Toledo (between Arequipa and Puno), of Gualillas
and Chullunquiani (between Arica and La Paz), all in the Western
Cordillera, attain the respective elevations of 16,160, 15,790,
14,750, and 15,160 feet;—whilst in the Eastern or Bolivian Cordillera
the passes of Challa (between Oruro and Cochabamba), of Pacuani
(between La Paz and Coröico), of Pumapacheta (between the lake of
Titicaca and the affluents to the Amazon), of Vilcañoto (between the
valley of the Collao and that of the river Yucay), rise to heights of
13,600, 15,350, 13,600, and 14,520 English feet.
Footnote 49:
Dr. Pœppig.
Footnote 50:
Baron Humboldt.
Footnote 51:
Baron Humboldt’s Personal Narrative.
Footnote 52:
Captain King, R. N., and Mr. Darwin.
Footnote 53:
Sir Woodbine Parish on Buenos Ayres, and Sir Francis Head’s Journey
over the Pampas.
Footnote 54:
Mr. Pentland found a very perfect volcanic crater, with well-marked
currents of lava issuing from it—a rare occurrence in the higher
craters of the Andes—near to San Pedro de Cacha, in the valley of the
Yucay (lat. 14° 12ʹ, long. 71° 15ʹ W., and at an elevation of 12,000
feet), near to the ruins of the Temple of the Inga Viracocha, a
monument and a locality celebrated in Peruvian legend, the nearest
point of the sea-coast being 175 miles distant. It is probable that
many of the most celebrated mining districts of Alto Peru—Potosi, for
instance, situated in a porphyry—have been upheaved at a very recent
period. Modern volcanic rocks are not wanting in the valley of the
Desaguadero; volcanic conglomerates exist in the deep ravines round
the city of La Paz. lat. 16° 30ʹ; and the mountain of Litanias, which
furnishes the building-stone for that Bolivian city (lat. 16° 42ʹ,
long. 68° 19-1/2ʹ), is composed of a most perfect trachyte, and rises
to a height of 14,500 feet above, and at a distance of 160 miles from
the Pacific.
Footnote 55:
Dr. Pœppig.
Footnote 56:
Mr. Pentland found fossil shells of the Silurian period at a height of
17,500 feet, on the Bolivian Nevado of Antakäua, lat. 16° 21ʹ, and
those of the carboniferous limestone as high as 14,200 in several
parts of Upper Peru.
Footnote 57:
Mr. Darwin’s Journal of Travels in South America.
Footnote 58:
Mr. Darwin’s Journal of Travels in South America.
Footnote 59:
Johnston’s Physical Atlas.
Footnote 60:
Baron Humboldt.
Footnote 61:
[Notes on the North-west, or Valley of the Upper Mississippi. By Wm.
J. A. Bradford. New York, 1846.]
Footnote 62:
Mr. Taylor.
Footnote 63:
Sir Charles Lyell’s Travels in North America.
Footnote 64:
A chain of mountains is assumed to be a three-sided horizontal prism,
whose height is the mean elevation of the chain, and the base the mean
length and breadth of the same, or the area on which the chain stands,
and thus its mass may be computed approximately. It is evident that a
table-land must have a greater effect on the mean height of a
continent than a chain of mountains, for, supposing both to be of the
same base and altitude, one would be exactly double the other; and
even if the mountains be the higher of the two, their upper parts
contain much less solid matter than their lower on account of the
intervals and deep valleys between the peaks.
Footnote 65:
The author is indebted to the “Physical Geography of North America” by
H. D. Rogers, Esq., of the United States, for much valuable
information.
Footnote 66:
Dr. Richardson on the Fauna of the High Latitudes of North America.
Footnote 67:
Sir Charles Lyell.
Footnote 68:
This remarkable analogy between the fossil remains of the Silurian
systems in the Old and New World has been more particularly shown by
the researches of Messrs. de Verneuil and Sharpe.
Footnote 69:
According to M. Charpentier, the area of the base of the Pyrenees is
1720 square English miles. As the mean elevation of the passes gives
the mean height of the mountains, Baron Humboldt estimated from the
height of 23 passes over the Pyrenees that the mean crest of that
chain is 7990 feet high, which is 300 feet higher than the mean height
of the Alps, though the peaks in the Alps have a greater elevation
than those of the Pyrenees in the ratio 1-4/10 to 1.
Footnote 70:
The Russian Academicians MM. Fuss and Bunge, found by barometrical
measurement the mean height of that part of the Eastern Asiatic
table-land lying between Lake Baikal and the Great Wall of China to be
only about 6960 feet. The smallness of this mean is owing to hollows
in the table-land, especially in the desert of the Great Gobi.
Footnote 71:
By the mensuration and computation of Baron Humboldt and Mr. Pentland,
the elevation of the highest peaks, and the mean heights of the
Himalaya, of the equatorial and Bolivian Andes and the Alps, are as
follows:—
Peaks. Mean Height.
Himalaya 25,700 15,670 Andes between 5° N. and 2° S. lat. 21,420 11,380 Eastern Cordillera } Between 18° { 21,200 15,250 Western Cordillera } and 15° S. lat. { 22,300 14,900 Alps 15,666 7,353
However, the Peak of Dhawalaghini is certainly 28,000 feet high.
Captain Gerard gives 18,000 or 19,000 feet as the height of the
snow-line on the mountains in the middle of the Asiatic table-land,
and 30,000 feet as the absolute elevation of the Kuen-lun, but Colonel
Sabine observes that these measures want confirmation.
Footnote 72:
Memoirs of Count Strzelecki.
Footnote 73:
Count Strzelecki.
Footnote 74:
M. Von Buch.
Footnote 75:
—— Mansel, Esq.
Footnote 76:
Mr. Darwin on Coral Reefs.
Footnote 77:
Supplement to the Observations on the Temple of Serapis, by Charles
Babbage, Esq.
Footnote 78:
By Mr. Jukes, Naturalist to the Surveying Voyage of Captain Blackwood,
R. N., in Torres Straits.
Footnote 79:
Another theory relative to the formation of the lagoon islands is,
that the coral circuit is but the edge of a submarine elevation
crater, on which the coral animals have raised their edifice. This
view, which has been adopted by Von Buch and Captain Beechy, to whom
we are indebted more than to any other navigator for positive
information and admirable surveys of the coral islands of the Pacific,
receives corroboration from the perfect conformity in shape between
many of the lagoon islands of the Gambier group and the known
elevation craters, and from the circumstance of a lagoon island having
been seen to rise in 1825, in lat. 30° 14ʹ, accompanied with smoke,
and communicating so high a temperature to the surrounding sea as
rendered it impossible to land.—See Beechy’s Voyages, and Pœppig’s
Reise.
Footnote 80:
Few books have more interest than Mr. Darwin’s on Coral Reefs and
Volcanic Islands, to which the author is much indebted. Consult also
Captain Beechy’s Voyages, and his beautiful charts of the Coral
Islands in the Pacific.
Footnote 81:
By the Nautical Survey in 1848.
Footnote 82:
Sir Stamford Raffles on Java.
Footnote 83:
Mr. Darwin on Volcanic Islands.
Footnote 84:
Mr. Douglas’s Voyage to the Sandwich Islands in 1833-4.—Journal of the
Royal Geographical Society of London.
Footnote 85:
Letter from Alex. Loudon, Esq., in the Journal of the Geographical
Society of London.
Footnote 86:
Mitchell on the Causes of Earthquakes, in Philosophical Transactions
for 1760.
Footnote 87:
Captain Graah’s Survey in 1823-4, and Dr. Pingel, 1830-2.
Footnote 88:
Lyell’s Principles of Geology, in 8vo. See also Mr. Darwin’s
observations on the same subject, in the voyage of the Adventure and
Beagle.
Footnote 89:
Remarks on the Antarctic Continent and Southern Islands, by Robert
MacCormick, Esq., Surgeon of H.M.S. Erebus.
Footnote 90:
Captain Cook discovered Sandwich Land in 1772-5.—Captain Smith, of the
brig William, discovered New South Shetland in 1819.—Captain
Billingshausen discovered Peter’s Island, and the coast of Alexander
the First.—Captain Weddel discovered the Southern Orcades.—Captain
Bisco discovered Enderby’s Land and Graham’s Land in 1832, Admiral
d’Urville La Terre d’Adelie in 1841; and Sir James Ross Victoria Land
in the same year.
Footnote 91:
The author owes much information on British mines to two publications
on the Mining District of the North of England, by J. Sopwith, Esq.,
Civil Engineer, and Mr. Leithart, Mine Agent. On the Cornish mines she
has derived much information from the writings of John Taylor, Esq.,
and Sir Charles Lemon, Bart.; from a store of valuable materials
contained in the “Progress of the Nation,” by G. R. Porter, Esq.; from
the Statistical Journal; and on the general distribution of minerals
over the globe, from the “Penny Cyclopædia,” and various other
sources.
Footnote 92:
The metals are gold, silver, platinum, copper, lead, tin, iron, zinc,
arsenic, bismuth, antimony, nickel, quicksilver, manganese, cadmium,
cerium, cobalt, iridium, uranium, chrome, lantanium, molybdenum,
columbium, osmium, palladium, pelapium, tantalum, tellurium, rhodium,
titanium, vanadium, tungsten, dydynium, ferbium, erbium. The three
last are little known.
Sir Humphry Davy discovered that lime, magnesia, alumine, and other
similar substances, are metals combined with oxygen. There are
thirteen of these metalloids, namely—calcium, magnesium, aluminum,
glucinum, thorium, yttrium, zirconium, strontium, barium, lithium,
natrium, potassium, and silicium.
Footnote 93:
This subject is ably discussed by Mr. Leithart in his work, already
mentioned, on the formation and filling of metallic veins. Mr.
Leithart is an instance of the intelligence that prevails among
miners, notwithstanding the scanty opportunities of acquiring that
knowledge which they are generally so eager to obtain. He was a
working miner, whose only education was at a Sunday-school.
Footnote 94:
Mineral veins are generally richer near the surface than at great
depths: this is particularly the case in the mines of the precious
metals in America, where the greatest quantities of ore have been
found near the surface—a fact that may be explained by supposing the
mineral substances brought by sublimation from the interior of the
earth, and deposited where the temperature was lowest at or near the
surface in the rocks among which they are situated.
Footnote 95:
Rotation alone produces electrical currents in the earth.—“Connection
of the Physical Sciences,” page 364, 7th edition.
Footnote 96:
J. Taylor, Esq., on Cornish mines.
Footnote 97:
The total amount of steam-power in Great Britain in 1833 was equal to
that of 2,000,000 of men.—J. Taylor, Esq., on Cornish Mines.
Footnote 98:
The splendid discovery of Sir Humphry Davy, that flame does not pass
through fine wire-gauze, prevents the fatal explosion of inflammable
air in the mines, by which thousands of lives have been lost. By means
of a light enclosed in a wire-gauze lantern, a miner now works with
safety surrounded by fire-damp. To the honour of the illustrious
author of this discovery, be it observed that it was not, like that of
gunpowder and others, the unforeseen result of chance by new
combinations of matter, but the solution of a question based on
scientific experiment and induction, which it required the genius of a
philosophic mind like his to arrive at.
Footnote 99:
Supposing the barometer to be 30 inches on the level of the sea.
Footnote 100:
Note to the English translation of Kosmos, by Colonel Sabine, on the
depths below the surface of the earth attained by man.
Footnote 101:
Dr. Pœppig’s “Travels in Chile and Peru.”
Footnote 102:
Dr. Pœppig.
Footnote 103:
Constructed under the direction of Thomas Sopwith, Esq.
Footnote 104:
Sir Charles Lemon, Bart.
Footnote 105:
M. Erman’s “Travels in Siberia.”
Footnote 106:
In 1841 there were 196,921 persons employed in the mines of Great
Britain and Ireland.
Footnote 107:
In the year 1829 the value of the mineral produce of Europe, including
Asiatic Russia, but exclusive of manganese, amounted to—
Gold and Silver £1,943,000 Other metals 28,519,000 Salts 7,640,000 Combustibles 18,050,000 ---------- Total £56,148,000
England contributed more than half this amount, namely,—
Silver £ 28,500 Copper 1,369,000 Iron 11,292,000 Lead 760,000 Tin 536,000 Salts 756,250 Vitriol 33,600 Alum 33,000 Coal 13,000,000 ---------- Total £28,716,750
—nearly £29,000,000 sterling.—John Taylor, Esq., on the Cornish Mines.
At present there are 34,000,000 of tons of coals consumed in Great
Britain annually, besides the quantity exported to our colonies and to
foreign countries, amounting to nearly 2,000,000 of tons. 8,000,000 of
tons are consumed in our iron-foundries alone. Between 500,000 and
600,000 tons are used in making gas.
The iron made in Britain in 1844 amounted to 1,400,000 tons. Iron is
now applied to many uses instead of timber, especially in
ship-building: between the years 1830 and 1847, 150 iron vessels were
launched in Britain. 25 of the steamships of the East India Company
are of iron.
The produce of our copper-mines has increased threefold within the
last 60 years. The quantity of tin has also increased from our own
mines, and also from the extensive importation of that metal from
Banca, where the country yielding stream-tin extends from 7° N. lat.
to 3° S. lat. The yearly produce amounts to 300 tons of pure metal.—
“Progress of the Nation, in its Social and Commercial Relations, since
the beginning of the Nineteenth Century,” by G. R. Porter, Esq., 2d
edition.
In France there are 62 coal-mines, which yielded 3,410,200 tons in
1841, and in 1838 the 12 iron districts in that country yielded to the
value of 4,975,424_l._
The British coal and metal imported into France amounted to
1,222,228_l._—Progress of the Nation.
Belgium is next to Britain as a European coal country. In Britain the
coalfields occupy one-twentieth part of the area of the country—in
Belgium one twenty-second part—in France one two hundred and tenth
part of its area.
The quantity of coal raised in one year is, according to “The
Statistics of Germany,” by R. Valpy, Esq.—
In Britain 347,000,000 tons
Belgium 4,000,000
France 3,783,000
Germany 3,000,000
[The following table exhibits the quantity and value of coal produced,
in the six principal coal countries in the world, in the year 1845:—
+-------+-----------------+-------------+------------+----------+-----------------------------+ | | | | Tons of | | Official estimated value at | | Order | | Square | Fuel | Relative | the places of production. | | in | COUNTRIES. | miles of | raised in | parts of +----------------+------------+ | 1845. | | Coal | the year | 1000. | United States | English | | | | formations. | 1845. | | Dollars. | Sterling. | +-------+-----------------+-------------+------------+----------+-----------------------------+ | 1 | Great Britain | 11,859 | 31,500,000 | 642 | $45,738,000 | £9,450,000 | | 2 | Belgium | 518 | 4,960,077 | 101 | 7,689,900 | 1,660,000 | | 3 | United States | 133,132 | 4,400,000 | 89 | 6,650,000 | 1,373,963 | | 4 | France | 1,719 | 4,141,617 | 84 | 7,663,000 | 1,603,106 | | 5 | Prussian States | Not defined | 3,500,000 | 70 | 4,122,945 | 856,370 | | 6 | Austrian States | Not defined | 659,340 | 14 | 800,000 | 165,290 | +-------+-----------------+-------------+------------+----------+-----------------------------+ | | Total | | 49,161,034 | 1000 | 72,663,845 | 15,108,729 | +-------+-----------------+-------------+------------+----------+-----------------------------+
The coal trade appears to be increasing in all parts of the world.
There are no authentic data from which the increasing production of
bituminous coal in the United States can be exactly deduced, but what
we have show that it is very rapid. The production of _anthracite_ may
be said to be entirely confined to the State of Pennsylvania, which
possesses a numerous and interesting group of coal basins, of various
sizes and characters.
In the year 1820, the anthracite coal trade commenced with 365 tons;
in 1827 it reached 48,047 tons; in 1837, 881,026 tons, and advanced to
3,000,000 tons in 1847.
The following table exhibits the production of smelted or manufactured
iron in different countries in the year 1845:—
1. Great Britain 2,200,000
2. United States 502,000
3. France 448,000
4. Russia 400,000
5. Zollverein, or Prussian States 300,000
6. Austria 190,000
7. Belgium 150,000
8. Sweden 145,000
9. Spain (in 1841) 26,000
10. All other European countries 50,000
---------
4,411,000
The rapid increase in the number of railroads and locomotive engines,
and the number of steam vessels employed in commerce, augments the
demand, proportionally, for iron and fuel.
At the commencement of 1847, the length of railroad completed and
partly finished in the principal countries of Europe and America was
20,000 miles, only a few thousand miles less than the entire
circumference of the globe.][108]
Footnote 108:
“Statistics of Coal.” By Richard Cowling Taylor, Philadelphia, 1848.
Footnote 109:
Sir Charles Lyell’s “Travels in the United States of North America.”
Footnote 110:
For the reason of this secular variation in the Moon’s distance, see
page 42 of “The Connection of the Physical Sciences.”
Footnote 111:
Every undulating motion consists of two distinct things—an advancing
form and a molecular movement. The motion of each particle is in an
ellipse lying wholly in a vertical plane, so that, after the momentary
disturbance during the passage of the wave, they return to their
places again.—“Theory of Waves,” by J. Scott Russell, Esq.
Footnote 112:
J. Scott Russell, Esq., on Waves.
Footnote 113:
Beechy’s Voyage to the Pacific.
Footnote 114:
By Captain Albrecht’s soundings.
Footnote 115:
By the measurement of M. Lepère in the French expedition to Egypt.—
“Annales du Bureau de Longitude,” 1836.
Footnote 116:
Proceedings of the Royal Geological Society, vol. ii., p. 210.
Footnote 117:
Baron Humboldt’s Personal Narrative.
Footnote 118:
Leonardo da Vinci was appointed Director of Hydraulic Operations in
Lombardy by the Duke of Milan, and during the time he was painting the
“Last Supper” he completed the Canal of Martesana, extending from the
Adda to Milan, and improved the course of the latter river from where
it emerges from the Lake of Como to the Po. By means of the Naviglio
Grande, the Martesana canal establishes a water communication between
the Adda and the Ticino, the Lakes of Como and Maggiore.
Footnote 119:
Dr. Beke on the Nile and its affluents.
Footnote 120:
Captain W. Allen, R. N.
Footnote 121:
It is in the space comprised between two of the eastern tributaries of
the Tigris, the Khaus and the Great Zab, or Abou Selman of the Arabs,
that the extensive ruins of Koyunjik, Khorsabad, and especially of
Nimroud, are situated, the last of which have been so satisfactorily
identified with the capital of Assyria—the ancient Nineveh—by our
enterprising and talented countryman Mr. Layard, to whose exertions,
under circumstances of peculiar difficulty, surrounded by every
privation, our national Museum is indebted for that magnificent
collection of Assyrian monuments which at this moment forms the
admiration of the British public. It is to be hoped that our
Government will follow up the researches commenced by Mr. Layard, and
that several of the gigantic sculptures removed by him, with such
perseverance and labour, to Bussorah, will ere long be added to the
riches of the British Museum.
See Mr. Layard’s work on “Nineveh and its Remains,” 2 vols. 8vo., and
his illustrated work in folio—the former one of the most interesting
narratives ever published on the antiquities of Central Asia.
Footnote 122:
M. Erman.
Footnote 123:
[Lieutenant W. F. Lynch, of the United States Navy, has recently
published an interesting and valuable narrative of an expedition to
the Dead Sea and River Jordan. According to his measurements and
surveys, the level of the Dead Sea is 1,316·7 feet below that of the
Mediterranean. The city of Jerusalem is 2,610·5 feet above the latter,
and 3,927·24 feet above the former sea. The greatest depth of the Dead
Sea is 1308 feet. Lieutenant Lynch states the density of the water of
the Dead Sea to be 1·13, that of distilled water being 1.]
Footnote 124:
The water of Lake Eltonsk contains chloride of calcium.
Footnote 125:
The water of the Dead Sea, according to Lieutenant Lynch, contains
26·42 per cent. of saline ingredients, one of which is chloride of
magnesium.
Footnote 126:
Professor Schoenbein of Basle attributes the peculiar smell, when
bodies are struck by lightning, to a principle existing in the
atmosphere, which he calls ozone, liberated by the decomposing action
of electricity, and possessing the same electrical characters as
bromine, chlorine, and iodine. He ascribes the luminous appearance of
the ocean to the action of that principle on the animal matter it
contains.
Footnote 127:
Annales des Sciences Géologiques, par M. Rivière, 1842.
Footnote 128:
The mean of any number of unequal quantities is equal to their sum
divided by their number: thus the mean temperature of the air at any
place during a year is equal to the sum of the mean temperature of
each month divided by 12. This method, however, will only give an
approximate value; therefore, to ascertain the mean annual temperature
at any place accurately, the mean of a number of years must be taken.
Footnote 129:
Lines drawn on a map or globe through all places where the mean annual
temperature is the same are isothermal lines.
Footnote 130:
For example, Professor Dove has found that the mean temperature of
December, January, and February, at Toronto in Canada, added to the
mean temperature of the same months at Hobart Town in Van Diemen’s
Land, exceeds the sum of the mean temperature of June, July, and
August, at the same places, added together, by 22°·7 of Fahrenheit.
Similar results, though varying in amount, were obtained for many
corresponding places in the two hemispheres, which establishes the law
given in the text.
Footnote 131:
In the same manner as isothermal lines are supposed to pass through
all parts of the globe where the mean temperature of the air is the
same, so the isogeothermal lines are supposed to pass through all
places where the mean heat of the ground is the same: the isotherial
lines are supposed to be drawn through all places having the same mean
summer temperature; and the isochimenal lines pass through all places
where the mean winter temperature is the same. The practice of
representing to the eye these lines on a map or terrestrial globe is
of the greatest use in following and understanding the complicated
phenomena of temperature and magnetism.
Footnote 132:
If the heights above the earth increase by equal quantities, as a foot
or a mile, the densities of the strata of air, or the heights of the
barometer which are proportional to them, will decrease in geometrical
progression: for example, if the height of the barometer at the level
of the sea be 29·922 inches, it will be 14·961 inches at the height of
18,000 feet, or one-half as great; it will be one-fourth as great at
the height of 36,000 feet, one-eighth at the height of 54,000 feet,
and so on.
Footnote 133:
A very ingenious little instrument, called the Aneroid Barometer, has
been lately invented in France; which, at the same time that it forms
an exact and very portable _weather_-glass, in the common acceptation
of that term, may be employed with considerable accuracy in
ascertaining differences of level. Although not to be compared, as an
instrument of precision, with the ordinary mercurial barometer, it is
infinitely more portable, and gives with promptitude and accuracy
small differences of level.
A friend of the author’s has recently tested it in the latter respect
on some of our railways, and found that observations made with it
carefully will give, on a line of 200 miles in extent, the relative
levels of the different stations within a few feet. The observations
can be made in a couple of minutes. The gentleman in question writes
to us, that he considers the Aneroid Barometer will prove a very
useful instrument to the geological and the botanical traveller.
See, for a description of this instrument, a pamphlet recently
published at 84, Strand, by Mr. E. J. Dent, on the Construction and
Uses of the Aneroid Barometer. London, 1849.
Footnote 134:
The moon’s orbit is very much elongated, so that her distance from the
earth varies considerably, and consequently her attractive force.
Moreover, her attraction varies with the rotation of the earth, which
brings her twice in 24 hours in the meridian of any place, once in the
superior and once in the inferior meridian; but her action on the
atmosphere is much inferior to that of the heat of the sun.
Footnote 135:
Mr. Pentland has, however, found in the Peru-Bolivian Andes, at
elevations between 11,000 and 14,000 feet, the horary oscillations of
the barometer as regular, and nearly as extensive, as on the level of
the sea in the same latitude.
Footnote 136:
Lieutenant Maury, of the United States Navy, is led to believe that
there is a region within the limit of the N.E. trade-winds, in the
Atlantic, in which the prevailing winds are from the south and west:
this region is somewhat in the shape of a wedge, with its base towards
the coast of Africa, between the equator and 10° N. lat., and between
the meridians of 10° and 25° W. long. In this space, in which the law
of the trade-winds is reversed, there are great atmospheric
disturbances, violent squalls, sudden gusts of wind, thunder, storms,
heavy rains, baffling airs, and calms.
Footnote 137:
In the northern hemisphere, a north wind sets out with a less rotatory
motion than the places have at which it successively arrives,
consequently it veers through all the points of the compass from N. to
N.E. and E. If a south wind should now spring up, it would gradually
veer from S. to S.W. and W., because its rotatory velocity would be
greater than that of the places it successively comes to. The
combination of the two would cause a vane to veer from E. to S.E. and
S.; but the rotation of the earth would now cause the south wind to
veer round from S. to S.W. and W.; and should a north wind now arise,
its combination with the west wind would bring the vane round from W.
to N.W. and N. again. At the Greenwich Observatory the wind makes five
gyrations in that direction in the course of a year. In Europe it is
the contention of the N.E. and S.W. winds which causes the rotation of
the wind, and the principal changes of weather, the S.W. being warm
and moist, the N.E. cold and dry, except where it comes over the
German Ocean.
Footnote 138:
In all hurricanes hitherto observed, the sinking of the mercury, and
the increase of the wind, have been more or less regularly progressive
till within three or four hours’ sail of the centre of the storm; and
in one class they have continued so even to the centre; while in
another class, and by far the most terrible, the depression of the
mercury has been sudden and excessive when within that distance of the
centre, and the violence of the tempest far beyond the average. When a
ship is within 50 or 60 miles of the centre, the storm has the
mastery, and seamanship is of little avail. Rules for avoiding this
calamity, and for managing a ship when involved in a hurricane, are
fully explained in the “Sailor’s Horn-Book for the Laws of Storms,” by
H. Piddington, Esq., President of the Marine Courts of Inquiry at
Calcutta. The following approximate table is given by him, to serve as
a guide till better data shall be obtained:—
Average fall of the Distance of a ship from the
barometer per hour. centre of the storm, in miles.
From 0·020 to 0·060 From 250 to 150
From 0·060 to 0·080 From 150 to 100
From 0·080 to 0·120 From 100 to 80
From 0·120 to 0·150 From 80 to 50
The rate of fall per hour doubles after the storm has lasted six
hours, and within three hours of the centre of the hurricane the
mercury will fall four times as fast, if it be of the violent class.
Colonel James Capper discovered the rotatory motions of storms, and W.
C. Redfield, Esq., of New York, was the first who determined their
laws. Colonel Reid, Governor of Barbadoes, and Dr. Thom, of the 86th
regiment, have also written on the subject.
Footnote 139:
The four subordinate forms of clouds are the cirro-stratus, composed
of little bands of filaments, more compact than the cirrus, forming
horizontal strata, which seem to be numerous thin clouds when in the
zenith, and at the horizon a long narrow band. The cumulo-stratus
consists of the summer-cloud, like snowy mountains heaped on one
another, which at sunrise have a black or bluish tint at the horizon,
and pass into the nimbus, or rain-cloud, which has a uniform grey
tint, fringed at the edges; and the fourth is the cirro-cumulus, a
combination of filaments and heaped-up cumuli or summer-clouds.
Footnote 140:
The reader is referred to the chart of the distribution of rain in the
Physical Atlas of Alexander Keith Johnston, Esq., where the value of
the practice referred to in note p. 27 is shown.
Footnote 141:
The reader is referred to the “Connection of the Physical Sciences”
for an account of Dr. Dalton’s theory of definite proportions, and the
relative weight of atoms.
Footnote 142:
The reader is referred to the 18th section of the “Physical Sciences”
for reflection, refraction, and absorption of light, and to the 19th
section for the constitution of the solar light and colours.
Footnote 143:
For the cause of mirage, see the “Connection of the Physical
Sciences.”
Footnote 144:
For phenomena and theory of polarized light, see section 21,
“Connection of the Physical Sciences.”
Footnote 145:
Every substance, whether solid or fluid, has its own polarizing angle.
Footnote 146:
The reader is referred to a plate in “Johnston’s Physical Atlas”
showing the phenomena of the polarization of the atmosphere.
Footnote 147:
See sections 28 and 29 of the “Connection of the Physical Sciences:”
on Electricity.
Footnote 148:
Sound travels at the rate of 1120 feet in a second in air at the
temperature of 62° of Fahrenheit; so if that number be multiplied by
the seconds elapsed between the flash of lightning and the thunder,
the result will be the distance in feet at which the stroke took
place.
Footnote 149:
Colonel Sabine’s Notes to “Kosmos.”
Footnote 150:
The foci are all of different intensities; that in the South Atlantic,
discovered by M. Erman, has the least intensity of the four, and the
other in the southern hemisphere, discovered by Sir James Ross, has
the greatest; taking 1 as the unit at the magnetic equator in Peru,
their intensities are as 2·071 and 0·706. In the northern hemisphere
the American focus is more intense than that in Siberia, which is
moving from west to east, while the minor focus in the southern
hemisphere is moving from east to west.
Footnote 151:
The author is indebted to the admirable and profound investigations of
Colonel Sabine for almost all she knows on the subject of terrestrial
magnetism. In these, and in his notes on the English translation of
“Kosmos,” the reader will find all that is most interesting on the
subject. In his own works there are plates of the course of the
different magnetic lines mentioned in the text.
Footnote 152:
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Physical GeographyChapter XL: Appendix (4)
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