5,233;Pole of the,493,500,505Electric Light, the,44Ellipse, the,136;eccentricity of,137;focus of,137;Kepler's discoveries respecting,136,138,142–144,505;the form which the orbit of a planet takes,136;the parallactic,444;variety of form of,139Enceladus,559Encke, and the distance of the Sun from the Earth,147,184;his comet,344–352Encke's comet,344–352;approach to Jupiter of,349;and Mercury,349;and the Sun,346;diminution in periodic time of,351;distance from Mercury of,347;disturbed by the Earth,350,and by Mercury,348;irregularities of,347,351;orbit of,346;periodical return of,351;Von Asten's calculations concerning,349–350Energy supplying the tides,539Ensisheim meteorite, the,393Equatorial diameter,196,497;telescope,14Eratosthenes,89Eros,236Eruptions,197Evening star,109,169Eye, structure of the,10FFaculæ of the Sun,37Fire ball of 1869,375Fire balls,374"Fixed" stars,503Flamsteed, first Astronomer-Royal,311;hisHistoria Cœlestis,311Focus of planetary ellipse,137–139Fomalhaut,413Fraunhofer,478Fraunhofer lines,48Fundy, Bay of, tides in,538GGalileo, achievements of,10;and Jupiter's satellites,267;and Saturn's rings,273,274;and the Pleiades,418Galle, Dr., and Neptune,328–330Gassendi, and the transit of Mercury,164;and the transit of Venus,178;lunar crater named after him,90Gauss, and the minor planet Ceres,232Gemini, constellation of,303,420Geminids, the,400Geologists and the lapse of time,453Geometers, Oriental,5Geometry, cultivation by the ancients of,6George III. and Sir W. Herschel,299,306Giant's Causeway,407Gill, Dr. D.,27;and Juno,243;and the minor planets,242;and the parallax of α Centauri,451;and the parallax of Mars,214Glacial period,518Gravitation, law of,122–149;and binary stars,437;and precession,497;and the Earth's axis,495,497,499;and the parabolic path of comets,340;and the periodical return of comets,343;and the weight of the Earth,203,204;illustrated by experiments,123,124,127,129–132;its discovery aided by lunar observations,108,125;its influence on the satellites,149;its influence on stars,149;its influence on tides,149;Le Verrier's triumphant proof of,330;Newton's discoveries,125,126,147;on the Moon,96;universality amongst the heavenly bodies,128,373Great Bear,27,28,241;configuration,410;double star in the,438;positions of,409,411Green, Mr., and Mars,220Greenwich Observatory,26,311Griffiths, Mr., and Jupiter,252Grimaldi,90Grubb, Sir Howard,14"Guards," the,412Gulliver's Travelsand the satellites of Mars,228HHadley's observations of Saturn,282Hall, Professor Asaph, and the satellites of Mars,225Halley, and the periodicity of comets,341–343;and the transit of Venus,180Heat, bearings on astronomy,513;in the interior of the Earth,197–199,514;of the Sun,515–526Heliometer, the,243Helium,55Henderson, and the distance of α Centauri,442,451Hercules, star cluster in,269,462Herodotus (lunar crater),90Herschel, Caroline,299,465Herschel, Sir John, address to British Association,328;address on the presentation of gold medal to Bessel,443;and Biela's comet,357;and nebulæ,464;letter toAthenœumon Adams's share in the discovery of Neptune,330Herschel, Sir W., and double stars,435,436;and Saturn,279;and Saturn's satellites,295;and the Empress Catherine,301;and the movement of solar system towards Lyra,457;discovery of satellite of Uranus by,308,309;discovery of Uranus by,305,308;early life of,299;friendship with Sir W. Watson of302;he makes his own telescopes,301;"King's Astronomer,"307;method of making his telescopes,302;musical talent of,299;organist of Octagon Chapel, Bath,300;pardon for desertion from George III.,299;passion for astronomy of,300,301;relinquishes musical profession,307;sidereal aggregation theory of,529;study of the nebulæ by,464–465,529Herschelian telescope,19Historia Cœlestis,311Hœdi, the,414Holmes's, Mr., comet (1892),355Horrocks, and the transit of Venus,179Howard, Mr., and the Benares meteorite,392Huggins, Sir W.,479,483;and nebulæ,472Huyghens, and Saturn's rings,275–278;discovers first satellite of Saturn,293Hyades, the,419Hydrogen in Sirius and Vega,479;in the Sun,50Hyginus,93Hyperion,559IIapetus,559Iberians, the,3Inquisition, the, and Galileo,10Iris,242Iron, dust in the Arctic regions,408;in the Sun,50;of meteorites, the,396;spectrum of,50JJanssen, M.,34,53;and the transit of Venus,177Juno,233,238Jupiter, ancient study of,6;and the Leonids,386;attraction of,248;axial rotation of,558;belts of,252;brilliancy of,257;composition of,250;covered with an atmosphere of clouds,253,254;density of,558;diameter of,247,558;distance from the Earth of,110,111;distance from the Sun of,246,558;habitability of,257;heat received from the Sun by,256;internal heat of,252,256,515;lack of permanent features of,253;lack of solidity of,248,253,254;moment of momentum of,554,555;occultation of,255;orbit of,114,115,246;path of, perturbed by the attraction of Saturn,316;periodic time of,558;a planet, or "wanderer,"111;red spot in 1878,253;revolution of,246;rotation of,201,202;satellites of,247,249,257–261,265,559;satellites of, and gravitation,266;satellites of, and the Copernican theory,267;shadow from satellites of,257;shape of,201,202,247,252;size of, compared with the Earth,19,246,248,and other planets,114;and the Sun,114;storms on,256;tides on,555;weight of,248,250,and Encke's comet,350KKeeler, Professor, and Saturn's ring,288Kempf, Dr., and the Sun's velocity,484Kepler, and comets,360;and laws of planetary motion,10;and meteors,386;and the orbit of Mars,209;explanation of his laws,147,148,533;his discovery of the shape of the planetary orbits,136,138;his first planetary law,138;lunar crater called after him,90;prediction of the transit of Venus and Mercury,163,178;second law,141;third law,142Kids, the,414Kirchhoff, and spectrum analysis,478Kirkwood, Professor, and the movements of Saturn's satellites,296Klinkerfues, Professor,390LLagrange, and the theory of planetary perturbation,320–322;his assumption of planetary rigidity,531L'Aigle meteorites, the,392Lalande, and Neptune,332,333Landscapes, lunar,98Lane, Mr. J. Homer,522Laplace, and the nebular theory,526;and the satellites of Jupiter,266;and the theory of planetary perturbation,320Lassell, Mr., and Saturn's eighth satellite,296;discovers Neptune's satellite,334Law of gravitation (seeGravitation)Laws of Planetary Motion (seePlanetary Motion)Lead in the Sun,50Ledger, Mr., and Mercury,163Leibnitz, lunar mountains named after him,93Lemonnier, and Uranus,312Leo, and shooting stars,380,420Leonids, attractions of planets on,386;breadth of stream of,387;change of shape of,383;decrease of,385;enormous number of,382;historical records,383;length of stream of,387;Le Verrier, and the cause of their introduction into the solar system,388;meteor shoal of,382;periodic return of,382;their connection with comets and Professor, Schiaparelli,388Leonis γ, value of velocity of,484Leverage by equatorial protuberance,498Le Verrier, and Mars,214;and the discovery of Neptune,324–332;and the introduction of the Leonids into the solar system,388;and the weight of Mercury,349Lexell's comet,370Libration,84Lick Observatory,16Light, aberration of,503–512;velocity of,261,262,265,505,512Linné,87,94Lion, the,420,421Little Bear, the,412Little Dog, the,420Livy, and meteorites,393Lloyd, Provost,407Lockyer, Sir Norman, and Betelgeuze,482;and solar light,52London, tides at,538Louvain, F. Terby, and Titan,295Lowell, Mr., and Mercury,165Lunar tides,548,549Lyra, motion of solar system towards,459Lyre, the,424;Nebula in,469Lyrids, the,400MMädler, and the lunar craters,88,90,91Magellanic clouds,463Magnesium, colour of flame from,46;in the Sun,50Magnetism, connection with Sun spots,42Manganese in the Sun,50Maraldi, and the rings of Saturn,279Mare crisium,83;fœcunditatis,83;humorum,83;imbrium,83,98;nectaris83;nubium,83;serenitatis,83;tranquillitatis,83;vaporum,83Mars, ancient study of,6;appearance of, through the telescope,218;atmosphere of,222;axial rotation of,558;canals on,220;density of,558;diameter of,558;distance, from the Earth of,213;distance from the Sun of,213,558;gravitation on,225;Le Verrier's discovery of,214;life improbable on,224;marking on,218;movements of,211–213;opposition of,209–211;orbit of,116,209,210,213;orbit of, and the laws of Kepler,209;parallax (1877), and Dr. D. Gill,214;periodic time of,558;a planet or "wanderer,"111;"Polar Caps" on,218,219;proximity to the Earth of,110;rising and setting of,209;rotation of,218;satellites of,225–228,558;size of compared with other planets,116,216;tides on,551;water and ice on,219,224Maximilian, Emperor,393Mayer, Tobias, and Uranus,312Measurement of the Earth,193–196Mediterranean, tides in the,537Mercury, ancient study of,6;antiquity of its discovery,155–157;atmosphere of,166;attraction on comets of,347;climate of,163;comparative proximity to the Earth of,111;composition of,160;crescent-shaped,160;density of,558;diameter of,558;distance from the Sun of,151,558;habitability of,163;movement of,160,161;its elliptic form,139,161;orbit of,114;period of revolution of,161;periodic appearances of,158;periodic time of,558;perturbations of,350;a planet or "wanderer,"111;revolution of,165;rotation of, and Professor Schiaparelli,165;size of, compared with other planets,116;surface of,162;transit of,152;transit of, and Gassendi's observations,164;transit of, predicted by Kepler,163;velocity of,162;weight of,166,349Meridian circle,
5,233;Pole of the,493,500,505Electric Light, the,44Ellipse, the,136;eccentricity of,137;focus of,137;Kepler's discoveries respecting,136,138,142–144,505;the form which the orbit of a planet takes,136;the parallactic,444;variety of form of,139Enceladus,559Encke, and the distance of the Sun from the Earth,147,184;his comet,344–352Encke's comet,344–352;approach to Jupiter of,349;and Mercury,349;and the Sun,346;diminution in periodic time of,351;distance from Mercury of,347;disturbed by the Earth,350,and by Mercury,348;irregularities of,347,351;orbit of,346;periodical return of,351;Von Asten's calculations concerning,349–350Energy supplying the tides,539Ensisheim meteorite, the,393Equatorial diameter,196,497;telescope,14Eratosthenes,89Eros,236Eruptions,197Evening star,109,169Eye, structure of the,10FFaculæ of the Sun,37Fire ball of 1869,375Fire balls,374"Fixed" stars,503Flamsteed, first Astronomer-Royal,311;hisHistoria Cœlestis,311Focus of planetary ellipse,137–139Fomalhaut,413Fraunhofer,478Fraunhofer lines,48Fundy, Bay of, tides in,538GGalileo, achievements of,10;and Jupiter's satellites,267;and Saturn's rings,273,274;and the Pleiades,418Galle, Dr., and Neptune,328–330Gassendi, and the transit of Mercury,164;and the transit of Venus,178;lunar crater named after him,90Gauss, and the minor planet Ceres,232Gemini, constellation of,303,420Geminids, the,400Geologists and the lapse of time,453Geometers, Oriental,5Geometry, cultivation by the ancients of,6George III. and Sir W. Herschel,299,306Giant's Causeway,407Gill, Dr. D.,27;and Juno,243;and the minor planets,242;and the parallax of α Centauri,451;and the parallax of Mars,214Glacial period,518Gravitation, law of,122–149;and binary stars,437;and precession,497;and the Earth's axis,495,497,499;and the parabolic path of comets,340;and the periodical return of comets,343;and the weight of the Earth,203,204;illustrated by experiments,123,124,127,129–132;its discovery aided by lunar observations,108,125;its influence on the satellites,149;its influence on stars,149;its influence on tides,149;Le Verrier's triumphant proof of,330;Newton's discoveries,125,126,147;on the Moon,96;universality amongst the heavenly bodies,128,373Great Bear,27,28,241;configuration,410;double star in the,438;positions of,409,411Green, Mr., and Mars,220Greenwich Observatory,26,311Griffiths, Mr., and Jupiter,252Grimaldi,90Grubb, Sir Howard,14"Guards," the,412Gulliver's Travelsand the satellites of Mars,228HHadley's observations of Saturn,282Hall, Professor Asaph, and the satellites of Mars,225Halley, and the periodicity of comets,341–343;and the transit of Venus,180Heat, bearings on astronomy,513;in the interior of the Earth,197–199,514;of the Sun,515–526Heliometer, the,243Helium,55Henderson, and the distance of α Centauri,442,451Hercules, star cluster in,269,462Herodotus (lunar crater),90Herschel, Caroline,299,465Herschel, Sir John, address to British Association,328;address on the presentation of gold medal to Bessel,443;and Biela's comet,357;and nebulæ,464;letter toAthenœumon Adams's share in the discovery of Neptune,330Herschel, Sir W., and double stars,435,436;and Saturn,279;and Saturn's satellites,295;and the Empress Catherine,301;and the movement of solar system towards Lyra,457;discovery of satellite of Uranus by,308,309;discovery of Uranus by,305,308;early life of,299;friendship with Sir W. Watson of302;he makes his own telescopes,301;"King's Astronomer,"307;method of making his telescopes,302;musical talent of,299;organist of Octagon Chapel, Bath,300;pardon for desertion from George III.,299;passion for astronomy of,300,301;relinquishes musical profession,307;sidereal aggregation theory of,529;study of the nebulæ by,464–465,529Herschelian telescope,19Historia Cœlestis,311Hœdi, the,414Holmes's, Mr., comet (1892),355Horrocks, and the transit of Venus,179Howard, Mr., and the Benares meteorite,392Huggins, Sir W.,479,483;and nebulæ,472Huyghens, and Saturn's rings,275–278;discovers first satellite of Saturn,293Hyades, the,419Hydrogen in Sirius and Vega,479;in the Sun,50Hyginus,93Hyperion,559IIapetus,559Iberians, the,3Inquisition, the, and Galileo,10Iris,242Iron, dust in the Arctic regions,408;in the Sun,50;of meteorites, the,396;spectrum of,50JJanssen, M.,34,53;and the transit of Venus,177Juno,233,238Jupiter, ancient study of,6;and the Leonids,386;attraction of,248;axial rotation of,558;belts of,252;brilliancy of,257;composition of,250;covered with an atmosphere of clouds,253,254;density of,558;diameter of,247,558;distance from the Earth of,110,111;distance from the Sun of,246,558;habitability of,257;heat received from the Sun by,256;internal heat of,252,256,515;lack of permanent features of,253;lack of solidity of,248,253,254;moment of momentum of,554,555;occultation of,255;orbit of,114,115,246;path of, perturbed by the attraction of Saturn,316;periodic time of,558;a planet, or "wanderer,"111;red spot in 1878,253;revolution of,246;rotation of,201,202;satellites of,247,249,257–261,265,559;satellites of, and gravitation,266;satellites of, and the Copernican theory,267;shadow from satellites of,257;shape of,201,202,247,252;size of, compared with the Earth,19,246,248,and other planets,114;and the Sun,114;storms on,256;tides on,555;weight of,248,250,and Encke's comet,350KKeeler, Professor, and Saturn's ring,288Kempf, Dr., and the Sun's velocity,484Kepler, and comets,360;and laws of planetary motion,10;and meteors,386;and the orbit of Mars,209;explanation of his laws,147,148,533;his discovery of the shape of the planetary orbits,136,138;his first planetary law,138;lunar crater called after him,90;prediction of the transit of Venus and Mercury,163,178;second law,141;third law,142Kids, the,414Kirchhoff, and spectrum analysis,478Kirkwood, Professor, and the movements of Saturn's satellites,296Klinkerfues, Professor,390LLagrange, and the theory of planetary perturbation,320–322;his assumption of planetary rigidity,531L'Aigle meteorites, the,392Lalande, and Neptune,332,333Landscapes, lunar,98Lane, Mr. J. Homer,522Laplace, and the nebular theory,526;and the satellites of Jupiter,266;and the theory of planetary perturbation,320Lassell, Mr., and Saturn's eighth satellite,296;discovers Neptune's satellite,334Law of gravitation (seeGravitation)Laws of Planetary Motion (seePlanetary Motion)Lead in the Sun,50Ledger, Mr., and Mercury,163Leibnitz, lunar mountains named after him,93Lemonnier, and Uranus,312Leo, and shooting stars,380,420Leonids, attractions of planets on,386;breadth of stream of,387;change of shape of,383;decrease of,385;enormous number of,382;historical records,383;length of stream of,387;Le Verrier, and the cause of their introduction into the solar system,388;meteor shoal of,382;periodic return of,382;their connection with comets and Professor, Schiaparelli,388Leonis γ, value of velocity of,484Leverage by equatorial protuberance,498Le Verrier, and Mars,214;and the discovery of Neptune,324–332;and the introduction of the Leonids into the solar system,388;and the weight of Mercury,349Lexell's comet,370Libration,84Lick Observatory,16Light, aberration of,503–512;velocity of,261,262,265,505,512Linné,87,94Lion, the,420,421Little Bear, the,412Little Dog, the,420Livy, and meteorites,393Lloyd, Provost,407Lockyer, Sir Norman, and Betelgeuze,482;and solar light,52London, tides at,538Louvain, F. Terby, and Titan,295Lowell, Mr., and Mercury,165Lunar tides,548,549Lyra, motion of solar system towards,459Lyre, the,424;Nebula in,469Lyrids, the,400MMädler, and the lunar craters,88,90,91Magellanic clouds,463Magnesium, colour of flame from,46;in the Sun,50Magnetism, connection with Sun spots,42Manganese in the Sun,50Maraldi, and the rings of Saturn,279Mare crisium,83;fœcunditatis,83;humorum,83;imbrium,83,98;nectaris83;nubium,83;serenitatis,83;tranquillitatis,83;vaporum,83Mars, ancient study of,6;appearance of, through the telescope,218;atmosphere of,222;axial rotation of,558;canals on,220;density of,558;diameter of,558;distance, from the Earth of,213;distance from the Sun of,213,558;gravitation on,225;Le Verrier's discovery of,214;life improbable on,224;marking on,218;movements of,211–213;opposition of,209–211;orbit of,116,209,210,213;orbit of, and the laws of Kepler,209;parallax (1877), and Dr. D. Gill,214;periodic time of,558;a planet or "wanderer,"111;"Polar Caps" on,218,219;proximity to the Earth of,110;rising and setting of,209;rotation of,218;satellites of,225–228,558;size of compared with other planets,116,216;tides on,551;water and ice on,219,224Maximilian, Emperor,393Mayer, Tobias, and Uranus,312Measurement of the Earth,193–196Mediterranean, tides in the,537Mercury, ancient study of,6;antiquity of its discovery,155–157;atmosphere of,166;attraction on comets of,347;climate of,163;comparative proximity to the Earth of,111;composition of,160;crescent-shaped,160;density of,558;diameter of,558;distance from the Sun of,151,558;habitability of,163;movement of,160,161;its elliptic form,139,161;orbit of,114;period of revolution of,161;periodic appearances of,158;periodic time of,558;perturbations of,350;a planet or "wanderer,"111;revolution of,165;rotation of, and Professor Schiaparelli,165;size of, compared with other planets,116;surface of,162;transit of,152;transit of, and Gassendi's observations,164;transit of, predicted by Kepler,163;velocity of,162;weight of,166,349Meridian circle,