Salt, spectrum of table,122Samarcand,107"Saros," Chaldean,76–78,84Satellites,26–27,37Saturn,20,22,34,37,108,236–243,258;comet family of,252;a puzzle to the early telescope observers,241–243;retrograde motion of satellite Phœbe,240,250,336;ring system of,241;satellites of,36,239–240;shadows of planet on rings and of rings on planet,237Schaeberle,95–96,303,316Schiaparelli,155,214,223Schickhard (lunar crater),199Schmidt,206Schönfeld,290Schuster,95Schwabe,136Scotland, solar eclipses visible in,89–90,92Sea of Serenity,205"Sea of Showers,"197"Seas" of moon,197,206Seasons on earth,174–175;on Mars,211Secondary bodies,26Seneca,95,260Septentriones,291Serenitatis, Mare,205"Seven Stars,"291"Shadow Bands,"69Shadow of earth, circular shape of,62–64Shadows on moon, inky blackness of,202Shakespeare,259,293Sheepshanks Telescope,119"Shining fluid" of Sir W. Herschel,328"Shooting Stars."SeeMeteorsShort (of Edinburgh),114"Showers, Sea of,"197Sickle of Leo,270–271,296Siderostat,118Silver,145Silvered mirrors for reflecting telescopes,116Sinus Iridum,197Sirius,280,282,284–285,288–290,297,303–304,320;companion of,303;stellar magnitude of,289Size of celestial bodies, how ascertained,59Skeleton telescopes,110Sky, international photographic survey of,290–291;light of the,323Slipher, E.C.,213,222Smithsonian Institution of Washington,98Snow on Mars,213Sodium,122,124,254Sohag,95Solar system,20–21,29–31;centre of gravity of,42;decay and death of,344Somniorum, Lacus,197Sound,125,166,331South pole of heavens,163,285,298–299Southern constellations,298–299Southern Cross.SeeCruxSpace,328Spain, early astronomy in,107;eclipse tracks across93,97–98Spectroheliograph,140Spectroscope,120,122,124–125,144–145,212,231;prominences first observed with,94,140,236Spectrum of chromosphere,132–133;of corona,133;of photosphere,132;of reversing layer,132,137;solar,122–123,127,132Speculum,111,116;metal,112Spherical bodies,29Spherical shape of earth, proofs of,158–161Spherical shapes of sun, planets, and satellites,160Spiral nebulæ,314–316,337–338Spring balance,166Spring tides,192Spy-glass,108"Square of the distance,"43–44Stannyan, Captain,90Star, mass of, how determined,305;parallax of, first ascertained,173,280Stars, the,20,124,126,278et seq.;brightness of,287,320;distances between,326–327;distances of some,173,280,320;diminution of, below twelfth magnitude,324;evolution of, from nebulæ,317–318;faintest magnitude of,288;number of those visible altogether,324;number of those visible to naked eye,288"Steam cracks,"221Steinheil,118Stellar system, estimated extent of,325–327;an organised whole,327;limited extent of,322–328,330;possible disintegration of,329Stiklastad, eclipse of,88Stone Age,285Stoney, G.J.,202,222Stonyhurst Observatory,100Story of the Heavens,271Streams of stars, Kapteyn's two,284Stroobant,196Stukeley,91Sulphur,145Summer,175,178Sun,Chaps XII. andXIII.;as a star,124,278,289;as seen from Neptune,246,304;chemical composition of,144–145;distance of, how ascertained,151,211;equator of,135–136,139;gravitation at surface of,129,138–139;growing cold of,343–344;mean distance of, from earth,47,211;motion of, through space,282–286,326;not a solid body,136;poles of,136;radiations from,130;revolution of earth around,170–173;stellar magnitude of,288–289;variation in distance of,66,178Sunspots,34,125,134–137,140–141,143–144,308;influence of earth on,144Suns and possible systems,50,286Superior conjunction,147–149Superior planets,22,146,209–210,229Swan (constellation).SeeCygnusSwift, Dean,224"Sword" of Orion,297,316Syrtis Major.SeeHour Glass Sea"SystematicParallax,"326Systems, other possible,50,286Tailsof comets,182Tamerlane,107Taurus (constellation),103,296–297,307"Tears of St. Lawrence,"273Tebbutt's Comet,257–258Telescope,33,55,107–108,149;first eclipse of moon seen through,104;of sun,90Telescopes, direct view reflecting,114;gigantic,111;great constructors of,117–118;great modern,117–118Tempel's Comet,274Temperature on moon,203;of sun,128Temporary (or new) stars,310–314Tennyson, Lord,109,296,334Terrestrial planets,229–230Terrestrial telescope,117Thales, Eclipse of,84Themis,240"Tidal drag,"180,188,208,344Tide areas,179–180Tides,178–180,338–339Time Machine,344Tin,145Titan,240Titius,245Total phase,71–72Totality,72;track of,66Trail of a minor planet,226–227Transit,62,150–154;of Mercury,62,151,154;of Venus,62,151–152,154,211Trifid Nebula,316Triple stars,300Tubeless telescopes,110–111,243Tubes used by ancients,110Tuttle's Comet,274Twilight,167,202Twinkling of stars,168Twins (constellation).SeeGeminiTycho Brahe,290,311Tycho (lunar crater),204UlughBeigh,107Umbra of sunspot,134–135Universe, early ideas concerning,17–18,158,177,342Universes, possibility of other,330–331Uranus,22–24,31,210,243,245,275;comet family of,252;discovery of,22,210,243;rotation period of34,245;satellites of,26,245;"year" in,35–36Ursa Major (constellation),279,281,291,295,314;minor,177,279,293–294Ursæ Majoris, (ζ) Zeta.SeeMizarVariablestars,307–310Variations in apparent sizes of sun and moon,67,80,178Vault, shape of the celestial,194–196Vega,177,278,280,282–283,285,290,294,302,307,323Vegetation on Mars,221,217–218;on moon,205Venus,20,22,31,71,90,108–109,111,Chap. XIV.,246,311;rotation period of,34,155Very, F.W.,314Vesta,225,227Violet (rays of light),121–122,125Virgil,19Volcanic theory of lunar craters,203–204,214Volume,38Volumes of sun and planets compared,38–39"Vulcan,"25Wallace, A.R., on Mars,220–223Water, lack of, on moon,201–202Water vapour,202,213,222Wargentin,103Warner and Swasey Co.,117Weather, moon and,206–207Weathering,202Webb, Rev. T.W.,204Weight,43,165–166Wells, H.G.,344Whale (constellation).SeeCetusWhewell,190Willamette meteorite,277Wilson, Mount,118Wilson, W.E.,313"Winged circle" (or "disc"),87Winter,175,178Witt,227Wolf, Max,226–227,232Wright, Thomas,319,334Wybord,89Xenophon,101Year,35"Year" in Uranus and Neptune,35–36Year, number of eclipses in a,68"Year of the Stars,"270Yellow (rays of light),121–122,124Yerkes Telescope Great,117,303Young,94,137,166Zenith,174Zinc,145Zodiacal light,181Zone of asteroids,30–31,227