Chapter I: HAVE endeavored, in the preceding part of my work, to explain and (18)

Olbers, comets, 104, 109; aerolites, 114, 118; on their planetary velocity, 121; on the supposed phenomena of ascending shooting stars, 123; their periodic return in August, 125; November stream, 126; prediction of a brilliant fall of shooting stars in Nov., 1867, 127; absence of fossil meteoric stones in secondary and tertiary formations, 131; zodiacal light, its vibration through the tails of comets, 143; on the transparency of celestial space, 152.

Olmsted, Denison of New Haven, Connecticut, observations of aerolites, 113, 118, 119, 124.

Oltmanns, Herr, observed continuously with Humboldt, at Berlin, the movements of the declination needle, 190, 191.

Ovid, his description of the volcanic Hill of Methone, 240.

Oviedo describes the weed of the Gulf Stream as Praderias de yerva (sea weed meadows), 308.

Palaeontology, 270-284.

Pallas, meteoric iron, 131.

Palmer, New Haven, Connecticut, on the prodigious swarm of shooting stars, Nov. 12 and 13, 1833, 124; on the non-appearance in certain years of the August and November fall of aerolites, 129.

Parallaxes of fixed stars, 88, 89; of the solar system, 145, 146.

Perry, Capt., on Auroras, their connection with magnetic perturbations, 197, 201; whether attended with any sound, 200; seen to continue throughout the day, 197; barometric observation at Port Bowen, 314, 315; rarity of electric explosions in northern regions, 337.

Patricius, St., his accurate conjectures on the hot springs of Carthage, 223, 224.

Peltier on the actual source of atmospheric electricity, 335, 336.

Pendulum, its scientific uses, 44; experiments with, 64, 166, 169, 170; employed to investigate the curvature of the earth's surface, 165; local attraction, its influence on the pendulum, and geognostic knowledge deduced from, 44, 45, 167, 168; experiments of Bessel, 64.

Pentland, his measurements of the Andes, 28.

Percy, Dr., on minerals artifically produced. See note by Translator, 268.

Permian system of Murchison, 277.

Perouse, La, expedition of, 186.

Persia, great comet seen in (1608), 139, 140.

Pertz on the large aerolite that fell in the bed of the River Narni, 116.

Peters, Dr., velocity of stones projected from Aetna, 122.

Peucati, Count Mazari, partial infection of calcareous beds by the contact of syenitic granite in the Tyrol, 262.

Phillips on the temperature of a coalmine at increasing depths, 174.

Philolaus, his astronomical studies, 65; his fragmentary writings, 68-71.

Philosophy of nature, first germ, 37.

Phosphorescence of the sea in the torrid zones, 202.

Physics, their limits, 50; influence of physical science on the wealth and prosperity of nations, 53; province of physical science, 59; distinction betweeen the physical 'history' and physical 'description' of the world, 71, 72; physical science, characteristics of its modern progress, 81.

Pindar, 227.

Plans, geodesic experiments in Lombardy, 168.

Planets, 89-99; present number discovered, 90. (See note by Translator on the most recent discoveries, 90, 91); Sir Isaac Newton on their composition, 132; limited physical knowledge of, 156, 157; Ceres, 64-92; Earth, 88-99; Juno, 64, 92-97, 106; Jupiter, 64, 87, 92-98, 202; Mars, 87, 91-94, 132; Mercury, 87, 92-94; Pallas, 64, 92; Saturn, 87, 92-94; Venus, 91-94, 202; Uranus, 90-94; planets which have the largest number of moons, 95, 96.

Plants, geographical distribution of, 346-350.

Plato on the heavenly bodies, etc., 69; interpretation of nature, 163; his geognostic views on hot springs, and volcanic igneous streams, 237, 238.

Pliny the elder, his Natural History, 73; on comets, 104; aerolites, 122, 123, 130; magnetism, 180; attraction of amber, 188; on earthquakes, 205, 207; on the flame of inflammable gas, in the district of Phasells, 223; rarity of jasper, 261; on the configuration of Africa, 292.

Pliny the younger, his description of the great eruption of Mount Vesuvius, and the phenomenon of volcanic ashes, 235.

Plutarch, truth of his conjecture that falling stars are celestial bodies, 133, 134.

Poisson on the planet Jupiter, 64; conjecture on the spontaneous ignition of meteoric stones, 118; zodiacal light, 141; theory on the earth's temperature, 172, 173, 174, 176, 177.

Polarization, chromatic, results of its discovery, 52; experiments on the light of comets, 105, 106.

Polybius, 291.

Posidonius on the Ligyran field of stones, 115, 116.

Pouilet on the actual source of atmospheric electricity, 335.

Prejudices against science, how originated, 38; against the study of the exact sciences, why fallacious, 40-52.

Prichard, his physical history of Mankind, 352.

Pseudo-Plato, 54.

Psychrometer, 332, 338.

Pythagoras, first employed the word Cosmos in its modern sense, 69.

Pythagoreans, their study of the heavenly bodies, 65; doctrine on comets, 103.

Quarterly Review, article on Terrestrial Magnetism, 192.

Quetelet on aerolites, 114; their periodic return in August, 125.

Races, human, their geographical distribution, and unity, 351, 359.

Rain drops, temperature of, 220; mean annual quantity in the two hemispheres, 333, 334.

Reich, mean density of the earth, as ascertained by the torsion balance, 170; temperature of the mines in Saxony, 174.

Reisch, Gregory, his "Margarita Philosophica," 58.

Remusat, Abel, Mongolian tradition on the fall of an aerolite, 116; active volcanoes in Central Asia, at great distances from the sea, 245.

Richardson, magnetic phenomena attending the Aurora, 197; whether accompanied by sound 200; influence on the magnetic needle of the Aurora, 201.

Riohamba, earthquake at, 204, 205, 208, 213, 214.

Ritter, Carl, on his "Geography in relation to Nature and the History of Man," 48, 67.

Robert, Eugene, on the ancient sea-line on the coast of Spitzbergen, 296.

Robertson on the permanency of the compass in Jamaica, 181.

Rocks, their nature and configuration, 228; geognostical classification into four groups, 248-251; i. rocks of eruption, 248, 251-253; ii. sedimentary rocks, 248, 254, 255; iii. transformed, or metamorphic rocks, 248, 259, 255, 256-269; iv. conglomerates, or rocks of detritus, 269, 270; their changes from the action of heat, 258, 259; phenomena of contact, 258-269; effects of pressure and the rapidity of cooling, 258, 267.

Rose, Gustav, on the chemical elements, etc., of various aerolites, 131; on the structural relations of volcanic rocks, 254; on crystals of feldspar and albite found in granite, 251; relations of position in which granite occurs, 252-269; chemical process in the formation of various minerals, 265-269.

Ross, Sir James, his soundings with 27,000 feet of line, 160; magnetic observations at the South Pole, 187; important results of the Antarctic magnetic expedition in 1839, 192; rarity of electric explosions in high northern regions, 337.

Rossell, M. de, his magnetic oscillation experiments, and their date of publication, 186, 187.

Rothmann, confounded the setting zodiscal light with the cessation of twilight, 143.

Rozier, observation of a steady luminous appearance in the clouds, 202.

Rumker, Encke's comet, 106.

Ruppell denies the existence of active volcanoes in Kordofan, 245.

Sabine, Edward, observations on days of unusual magnetic disturbances, 178; recent magnetic observations, 184, 185, 187, 188.

Sagra, Ramon de la, observations on the mean annual quantity of rain in the Havana, 333.

Saint Pierre, Bernardin de, Paul and Virginia, 26; Studies of Nature, 347.

Salses or mud volcanoes, 224-228; striking phenomena attending their origin, 224, 225.

Salt works, depth of 158, 159; temperature, 174.

Santorino, the most important of the islands of eruption, 241, 242; description of. See note by Translator, 241.

Sargasso Sea, its situation, 308.

Satellites revolving round the primary planets, their diameter, distance, rotation, etc., 94, 99; Saturn's 96-98, 127' Earth's see Moon, Jupiter's, 96, 97; Uranus, 96-98.

Saurians, flying, fossil remains of, 274, 275.

Saussure, measurements of the marginal ledge of the crater of Mount Vesuvius, 232; traces of ammoniacal vapors in the atmosphere, 311; hygrometric measurements with Humboldt, 334-336.

Schayer, microscopic organisms in the ocean, 342, 343.

Scheerer on the identity of eleolite and nepheline, 253.

Schelling on nature, 55; quotation from his Giordino Bruino, 77.

Scheuchzner's fossil salamander, conjectured to be an antediluvian man, 274.

Schiller, quotation from, 36.

Schnurrer on the obscuration of the sun's disk, 133.

Schouten, Cornelius, in 1616 found the declination null in the Pacific, 182.

Schouw, distribution of the quantity of rain in Central Europe, 333.

Schrieber on the fragmentary character of meteoric stones, 117.

Scientific researches, their frequent result, 50; scientific knowledge a requirement of the present age, 53, 54; scientific terms, their vagueness and misapplication, 58, 68.

Scina, Abbate, earthquakes unconnected with the state of the weather, 206, 207.

Scoresby, rarity of electric explosions in high northern regions, 337.

Sea. See Ocean.

Seismometer, the, 205.

Seleucus of Erythrea, his astronomical studies, 65.

Seneca, noticed the direction of the tails of comets, 102; his views on the nature and paths of comets, 103, 104; omens drawn from their sudden appearance, 111; the germs of later observations on earthquakes found in his writings, 207; problematical extinction and sinking of Mount Aetna, 227, 240.

Shoals, atmospheric indications of their vicinity, 309.

Sidereal systems, 89, 90.

Siljerstrom, his observations on the Aurora, with Lottin and Bravais, on the coast of Lapland, 195.

Sirowatskoi, "Wood Hills" in New Siberia, 281.

Snow-line of the Himalayas, 30-33, 331, 334; of the Andes, 330; redness of long-fallen snow, 344.

Solar system, general description, 90-154; its position in space, 89; its transistory motion, 145-150.

Solinus on mud volcanoes, 225.

Sommering on the fossil remains of the large vertebrata, 274.

Somerville, Mrs., on the volume of fire-balls and shooting stars, 116; faintness of light of planetary nebulae, 141.

Southern celestial hemisphere, its picturesque beauty, 85, 86.

Spontaneous generation, 345, 346.

Springs, hot and cold, 219-225; intermittent, 219; causes of their temperature, 220-222; thermal, 222, 345; deepest Artesian wells the warmest, observed by Arago, 223; salses, 224-226; influence of earthquake shocks on hot springs, 210, 222-224.

Stars, general account of, 85-90; fixed 89, 90, 104; double and multiple, 89, 147; nebulous, 85, 86, 151, 152; their translatory motion, 147-150; parallaxes and distances, 147-149; computations of Bessel and Herschel on their diameter and volume, 148; immense number in the Milky Way, 150, 151; star dust, 85; star gaugings, 150; starless spaces, 150, 152; telescopic stars, 152; velocity of the propagation of light of, 153, 154; apparition of new stars, 153.

Storms, magnetic and volcanic. See Magnetism, Volcanoes.

Strabo, observed the cessation of shocks of erthquake on the eruption of lava, 215; on the mode in which islands are formed, 227; description of the Hill of Methone, 240; volcanic theory, 243; divined the existence of a continent in the northern hemisphere between Theria and Thine, 289; extolled the varied form of our small continent as favorable to the moral and intellectual development of its people, 291, 292.

Struve, Otho, on the proper motion of the solar system, 146; investigations on the propagation of light, 153; parallaxes and distances of fixed stars, 153; observations on Halley's comet, 105.

Studer, Professor, on mineral metamorphism. See note by Translator, 248.

Sun, magnitude of its volume compared with that of the fixed stars, 136; obscuration of its disk, 132; rotation round the center of gravity of the whole solar system, 145; velocity of its translatory motion, 145; narrow limitations of its atmosphere as compared with the nucleus of other nebulous stars, 141; "sun stones" of the ancients, 122; views of the Greek philosophers on the sun, 122.

Symond, Lieut., his trigonometrical survey of the Dead Sea, 296, 297.

Tacitus, distinguished local climatic relations from those of race, 352.

Temperature of the globe, see Earth and Ocean; remarkable uniformity over the same spaces of the surface of the ocean, 303; zones at which occur the maxima of the oceanic temperature, 319; causes which lower the temperature, 319, 320; temperature of various places, annual, and in the different seasons, 322, 323-328; thermic scale of temperature, 324, 325; of continental climates as compared with insular and littoral climates, 321, 322; law of decrease with increase of elevation, 327; depression of, by shoals, 309; refrigeration of the lower strata of the ocean, 303.

Teneriffe, Peak of its striking scenery, 26.

Theodectes of Phaselis on the color of the Ethiopians, 353.

Theon of Alexandria described comets as "wandering light clouds," 100.

Theophylactus described Scythia as free from earthquakes, 204.

Thermal scales of cultivated plants, 324, 325.

Thermal springs, their temperature, constancy, and change, 221-224; animal and vegetable life in, 345.

Thermometer, 338.

Thibet, habitability of its elevated plateaux, 331, 332.

Thienemann on the Aurora, 197, 200.

Thought, results of its free action, 53, 54; union with language, 56.

Tiberias, Sea of, its depression below the level of the Mediterranean, 296.

Tides of the ocean, their phenomena, 305, 306.

Tillard, Capt., on the sudden appearance of the island of Sabrina, 242.

Tournefort, zones of vegetation on Mount Ararat, 347.

Tralles, his notice of the negative electricity of the air near high waterfalls, 336.

Translator, notes by, 29; on the increase of the earth's internal heat with increase of depth, 45; silicious infusoria and animalculites, 46; chemical analysis of an aerolite, 64; on the recent discoveries of planets, 90, 91; observed the comet of 1843, at New Bedford, Massachusetts, in bright sunshine, 101; on meteoric stones, 111; on a MS., said to be in the library of Christ's College, Cambridge, 124; on the term "salses," 161; on Holberg's satire, "Travels in the World under Ground," 171; on the Aurora Borealis of Oct. 24, 1847, 194, 195, 199; on the electricity of the atmosphere during the Aurora, 200; on volcanic phenomena, 203, 204; description of the seismometer, 205; on the great earthquake of Lisbon, 210; impression made on the natives and foreigners by earthquakes in Peru, 215; earthquakes at Lima, 216, 217; on the gaseous compounds of sulphur, 217, 218; on the Lake of Lasch, its craters, 218; on the emissions of inflammable gas in the district of Phasells, 233; on true volcanoes as distinguished from salses, 224; on the volcano of Pichincha, 228; on the hornitos de Jorullo, as seen by Humboldt, 230; general rule on the dimensions of craters, 230; on the ejection of fish from the volcano of Imbaburn, 223; on the little isle of Volcano, 234; volcanic steam of Pantellaria, 235; on Daubeney's work "On Volcanoes," 236; account of the island of Santorino, 241; on the vicinity of extinct volcanoes to the sea, 244; meaning of the Chinese term "li," 245; on mineral metamorphism, 248; on fossil human remains found in Guadaloupe, 250; on minerals artifically produced 267, 268; fossil organic structures, 271, 272; on Coprolites, 271; geognostic distribution of fossils, 276; fossil fauna of the Sewalik Hills, 278; thickness of coal measures, 281; on the amber pine forests of the Baltic, 283, 284; elevation of mountain chains, 286, 287; the dinornis of Owen, 287; depth of the atmosphere, 302; richness of organic life in the ocean, 309; on filaments of plants resembling the spermatozoa of animals, 341; on the Diatomaceae in the South Arctic Ocean, 343; on the distribution of the floras and faunas of the British Isles, 348, 349; on the origin and diffusion of the British flora, 353, 354.

Translatory motion of the solar system, 145-150.

Trogus, Pompeius, on the supposed necessity that volcanoes were dependent on their vicinity to the sea for their continuance, 243, 244; views of the ancients on spontaneous generation, 346.

Tropical latitudes, their advantages for the contemplation of nature, 33; powerful impressions from their organic richness and fertility, 34; facilities they present for a knowledge of the laws of nature 35; transparency of the atmosphere, 114; phosphorescence of the sea, 202.

Tschudi, Dr., extract from his "Travels in Peru." See Translator's note, 215, 216, 217.

Turner, note on Sir Isaac Newton, 132.

Universality of animated life, 342, 343.

Valz on the comet of 1618, 106.

Varenius, Bernhard, his excellent general and comparative Geography, 66, 67; edited by Newton, 66.

Vegetable world, as viewed with microscopic powers of vision, 341; its predominance over animal life, 343.

Vegetation, its varied distribution on the earth's surface, 29-31, 62; richness and fertility in the tropics, 33-35; zones of vegetation on the declivities of mountains, 29-32, 346-350. See Aetna, Cordilleras, Himalayas, Mountains.

Vico, satellites of Saturn, 96.

Vigne, measurement of Ladak, 322.

Vine, thermal scale of its cultivation, 324.

Volcanoes, 28, 30, 35, 159, 161, 214, 215, 224-248; author's application of the term volcanic, 45; active volcanoes, safety-valves for their immediate neighborhood, 214; volcanic eruptions, 161, 210-270; mud volcanoes or salses, 224-228; traces of volcanic action on the surface of the earth and moon, 228; influence of relations of height on the occurrence of eruptions, 228-233; volcanic storm, 233; volcanic ashes, 233; classification of volcanoes into central and linear, 238; theory of the necessity of their proximity to the sea, 243-246; geographical distribution of still active volcanoes, 245-247; metamorphic action on rocks, 247-249.

Vrolik, his anatomical investigations on the form of the pelvis, 352, 353.

Wagner, Rudolph, notes on the races of Africa, 352.

Walter on the decrease of volcanic activity, 215.

Wartmann, meteors, 113, 114.

Weber, his anatomical investigations on the form of the pelvis, 353.

Webster, Dr. (of Harvard College, U.S.), account of the island named Sabrina. See note by Translator, 242.

Winds, 315-321; monsoons, 316, 317; trade winds, 32-, 321; law of rotation, importance of its knowledge, 315-317.

Wine on the temperature required for its cultivation, 324; thermic table of mean annual heat, 325.

Wolleston on the limitation of the atmosphere, 302.

Wrangel, Admiral, on the brilliancy of the Aurora Borealis, coincident with the fall of shooting stars, 126, 127; observations of the Aurora, 197, 200; wood hills of the Siberian Polar Sea, 281.

Xenophanes of Colophon, described comets as wandering light clouds, 100; marine fossils found in marble quarries, 263.

Young, Thomas, earliest observer of the influence different kinds of rocks exercise on the vibrations of the pendulum, 168.

Yul-sung, described by Chinese writers as "the realm of pleasure," 332.

Zimmerman, Carl, hypsometrical remarks on the elevation of the Himalayas, 32.

Zodiacal light, conjectures on, 86-92; general account of, 137-144; beautiful appearance, 137, 138; first described in Childrey's Britannia Baconica, 138; probable causes, 141; intensity in tropical climates, 142.

Zones, of vegetation, on the declivities of mountains, 29-33; of latitude, their diversified vegetation, 62; of the southern heavens, their magnificence, 85, 86; polar, 197, 198.

END OF VOL. I.