[Footnote 1648: Trans. R. Dublin Soc., vol. iii., p. 61.]

[Footnote 1649: Observatory, vol. vii., p. 167.]

[Footnote 1650: Loewy, Bull. Astr., t. i., p. 265.]

[Footnote 1651: Phil. Trans., vol. clxxi., p. 653.]

[Footnote 1652: Janssen, L'Astronomie, t. ii., p. 121.]

[Footnote 1653: Rev. A. L. Cortie, Astr. and Astrophysics, vol. xi., p. 400.]

[Footnote 1654: Phil. Mag., vol. xiii., 1882, p. 469.]

[Footnote 1655: Bull. Astr., t. iii., p. 331.]



APPENDIX

TABLE I

CHRONOLOGY, 1774-1893

1774, March 4 Herschel's first observation. Subject, the Orion Nebula. 1774 Sun-spots geometrically proved to be depressions by Wilson. 1774 First experimental determination of the earth's mean density by Maskelyne. 1781, March 13 Discovery of Uranus. 1782 Herschel's first Catalogue of Double Stars. 1783 Herschel's first investigation of the sun's movement in space. 1783 Goodricke's discovery of Algol's law of variation. 1784 Analogy between Mars and the Earth pointed out by Herschel. 1784 Construction of the Heavens investigated by Herschel's method of star-gauging. "Cloven-disc" plan of the Milky Way. 1784 Discovery of binary stars anticipated by Michell. 1786 Herschel's first Catalogue of Nebulae. 1787, Jan. 11 Discovery by Herschel of two Uranian moons (Oberon and Titania). 1787, Nov. 19 Acceleration of the moon explained by Laplace. 1789 Herschel's second Catalogue of Nebulae, and classification by age of these objects. 1789 Completion of Herschel's forty-foot reflector. 1789, Aug. 28 His discovery with it of the two inner Saturnian and Sept. 17 satellites. 1789 Repeating-circle invented by Borda. 1789 Five-foot circle constructed by Ramsden for Piazzi. 1790 Maskelyne's Catalogue of thirty-six fundamental stars. 1791 Herschel propounds the hypothesis of a fluid constitution for nebulae. 1792 Atmospheric refraction in Venus announced by Schroeter. 1794 Rotation-period of Saturn fixed by Herschel at 10h. 16m. 1795 Herschel's theory of the solar constitution. 1796 Herschel's first measures of comparative stellar brightness. 1796 Laplace's Nebular Hypothesis published in Exposition du Systeme du Monde. 1797 Publication of Olbers's method of computing cometary orbits. 1798 Retrograde motions of Uranian satellites detected by Herschel. 1799 Publication of first two volumes of Mecanique Celeste. 1799, May 7 Transit of Mercury observed by Schroeter. 1799, Nov. 12 Star-shower observed by Humboldt at Cumana. 1800 Monatliche Correspondenz started by Von Zach. 1800 Invisible heat-rays detected in the solar spectrum by Herschel. 1801, Jan. 1 Discovery of Ceres by Piazzi. 1801 Publication of Lalande's Histoire Celeste. 1801 Investigation by Herschel of solar emissive variability in connection with spot-development. 1802, March 28 Discovery of Pallas by Olbers. 1802 Herschel's third Catalogue of Nebulae. 1802 Herschel's discovery of binary stars. 1802 Marks of clustering in the Milky Way noted by Herschel. 1802 Wollaston records seven dark lines in the solar spectrum. 1802, Nov. 9 Transit of Mercury observed by Herschel. 1804, Sept. 2 Discovery of Juno by Harding. 1804 Foundation of Optical Institute at Munich. 1805 Herschel's second determination of the solar apex. 1807, March 29 Discovery of Vesta by Olbers. 1811 Herschel's theory of the development of stars from nebulae. 1811, Feb. 9 Death of Maskelyne. Pond appointed to succeed him as Astronomer-Royal. 1811, Sept. 12 Perihelion passage of great comet. 1812 Theory of electrical repulsion in comets originated by Olbers. 1812, Sept. 15 Perihelion passage of Pons's comet. 1814 Herschel demonstrates the irregular distribution of stars in space. 1815 Fraunhofer maps 324 dark lines in the solar spectrum. 1818 Publication of Bessel's Fundamenta Astronomiae. 1819 Recognition by Encke of the first short-period comet. 1819, June 26 Passage of the earth through the tail of a comet. 1820 Foundation of the Royal Astronomical Society. 1821 Foundation of Paramatta Observatory. 1821, September First number of Astronomische Nachrichten. 1822, May 24 First calculated return of Encke's comet. 1822, August 25 Death of Herschel. 1823 Bessel introduces the correction of observations for personal equation. 1823 Fraunhofer examines the spectra of fixed stars. 1824 Distance of the sun concluded by Encke to be 95-1/4 million miles. 1824 Publication of Lohrmann's Lunar Chart. 1824 Dorpat refractor mounted equatoreally. 1826 Commencement of Schwabe's observations of sun-spots. 1826, Feb. 27 Biela's discovery of a comet. 1827 Orbit of a binary star calculated by Savary. 1829 Completion of the Royal Observatory at the Cape of Good Hope. 1829 The Koenigsberg heliometer mounted. 1830 Publication of Bessel's Tabulae Regiomontanae. 1832 Discovery by Brewster of "atmospheric lines" in the solar spectrum. 1833 Magnetic observatory established at Gottingen. 1833, Nov. 12,13 Star-shower visible in North America. 1833 Completion of Sir J. Herschel's survey of the northern heavens. 1834, Jan. 16 Sir J. Herschel's landing at the Cape. 1835, September Airy appointed Astronomer-Royal in succession to Pond. 1835, Nov. 16 Perihelion passage of Halley's comet. 1837 Solar movement determined by Argelander. 1837 Bessel's application of the heliometer to measurements of stellar parallax. 1837 Publication of Beer and Maedler's Der Mond. 1837 Publication of Struve's Mensurae Micrometricae. 1837, Dec. 16 Outburst of Eta Carinae observed by Sir J. Herschel. 1837 Thermal power of the sun measured by Herschel and Pouillet. 1838 Parallax of 61 Cygni determined by Bessel. 1839, Jan. 9 Parallax of Alpha Centauri announced by Henderson. 1839 Completion of Pulkowa Observatory. 1839 Solidity of the earth concluded by Hopkins. 1840, March 2 Death of Olbers. 1840 First attempt to photograph the moon by J. W. Draper. 1842 Doppler enounces principle of colour-change by motion. 1842 Conclusion of Baily's experiments in weighing the Earth. 1842, July 8 Total solar eclipse. Corona and prominences observed by Airy, Baily, Arago, and Struve. 1843, Feb. 27 Perihelion-passage of great comet. 1845, February Completion of Parsonstown reflector. 1845, April Discovery with it of spiral nebulae. 1845, April 2 Daguerreotype of the sun taken by Foucault and Fizeau. 1845, Oct. 21 Place of Neptune assigned by Adams. 1845, Dec. 8 Discovery of Astraea by Hencke. 1845, Dec. 29 Duplication of Biela's comet observed at Yale College. 1846 Melloni's detection of heating effects from moonlight. 1846, March 17 Death of Bessel. 1846, Sept. 23 Discovery of Neptune by Galle. 1846, Oct. 10 Neptune's satellite discovered by Lassell. 1847 Publication of Sir J. Herschel's Results of Observations at the Cape of Good Hope. 1847 Cyclonic theory of sun-spots stated by him. 1848 J. R. Mayer's meteoric hypothesis of solar conservation. 1848 Motion-displacements of Fraunhofer lines adverted to by Fizeau. 1848, April 27 New Star in Ophiuchus observed by Hind. 1848, Sept. 19 Simultaneous discovery of Hyperion by Bond and Lassell. 1849 First experimental determination of the velocity of light (Fizeau). 1850, July 17 Vega photographed at Harvard College. 1850, Nov. 15 Discovery by Bond of Saturn's dusky ring. 1851 O. Struve's first measurements of Saturn's ring-system 1851, July 28 Total solar eclipse observed in Sweden. 1851, Oct. 24 Discovery by Lassell of two inner Uranian satellites. 1851 Schwabe's discovery of sun-spot periodicity published by Humboldt. 1852, May 6 Coincidence of magnetic and sun-spot periods announced by Sabine. 1852, Oct. 11 Variable nebula in Taurus discovered by Hind. 1852 Lassell's two-foot reflector transported to Malta. 1853 Adams shows Laplace's explanation of the moon's acceleration to be incomplete. 1854 Hansen infers from lunar theory a reduced value for the distance of the sun. 1854 Helmholtz's "gravitation theory" of solar energy. 1856 Piazzi Smyth's observations on the Peak of Teneriffe. 1857 Saturn's rings shown by Clerk Maxwell to be of meteoric formation. 1857, April 27 Double-star photography initiated at Harvard College. 1858 Solar photography begun at Kew. 1858, Sept. 30 Perihelion of Donati's comet. 1859 Spectrum analysis established by Kirchhoff and Bunsen. 1859 Carrington's discovery of the compound nature of the sun's rotation. 1859, Sept. 1 Luminous solar outburst and magnetic storm. 1859, Oct. 19 Merope nebula discovered by Tempel. 1859, Dec. 15 Chemical constitution of the sun described by Kirchhoff. 1860, Feb. 27 Discovery by Liais of a "double comet." 1860, May 21 New star in Scorpio detected by Auwers. 1860, July 18 Total solar eclipse observed in Spain. Prominences shown by photography to be solar appendages. 1861, June 30 The earth involved in the tail of a great comet. 1861-1862 Kirchhoff's map of the solar spectrum. 1862 Solar hydrogen-absorption recognised by Angstrom. 1862, Jan. 31 Discovery by Alvan G. Clark of the companion of Sirius. 1862 Foucault determines the sun's distance by the velocity of light. 1862 Opposition of Mars. Determination of solar parallax. 1862 Completion of Bonner Durchmusterung. 1863 Secchi's classification of stellar spectra. 1863 Foundation of the German Astronomical Society. 1864, March 5 Rotation period of Mars determined by Kaiser. 1864 Huggins's first results in stellar spectrum analysis. 1864, Aug. 5 Spectroscopic examination of Tempel's comet by Donati shows it to be composed of glowing gas. 1864, Aug. 29 Discovery by Huggins of gaseous nebulae. 1864 Value of 91,000,000 miles adopted for the sun's distance. 1864 Croll's explanation of glacial epochs. 1864, Nov. 23 Death of Struve. 1865, Jan. 4 Spectroscopic observation by Huggins of the occultation of Eta Piscium. 1865, Jan. 16 Faye's theory of the solar constitution. 1865 Kew results published. 1865 Zoellner argues for a high temperature in the great planets. 1866 Identity of the orbits of the August meteors and of comet 1862 iii. demonstrated by Schiaparelli. 1866 Delaunay explains lunar acceleration by a lengthening of the day through tidal friction. 1866, March 4 Spectroscopic study of the sun's surface by Lockyer. 1866, March 12 New star in Corona Borealis detected by Birmingham. 1866, October Schmidt announces the disappearance of the lunar crater Linne. 1866, Nov. 13 Meteoric shower visible in Europe. 1867 Period of November meteors determined by Adams. 1867, Aug. 29 Total solar eclipse. Minimum sun-spot type of corona observed by Grosch at Santiago. 1867 Discovery of gaseous stars in Cygnus by Wolf and Rayet. 1868, February Principle of daylight spectroscopic visibility of prominences started by Huggins. 1868, Aug. 18 Great Indian eclipse. Spectrum of prominences observed. 1868, Aug. 19 Janssen's first daylight view of a prominence. 1868, Oct. 26 Lockyer and Janssen independently announce their discovery of the spectroscopic method. 1868 Doppler's principle applied by Huggins to measure stellar radial movements. 1868 Publication of Angstrom's map of the normal solar spectrum. 1868 Spectrum of Winnecke's comet found by Huggins to agree with that of olefiant gas. 1869, Feb. 11 Tenuity of chromospheric gases inferred by Lockyer and Frankland. 1869, Feb. 13 Huggins observes a prominence with an "open slit." 1869, Aug. 7 American eclipse. Detection of bright-line coronal spectrum. 1870 Mounting of Newall's 25-inch achromatic at Gateshead. 1870 Proctor indicates the prevalence of drifting movements among the stars. 1870 A solar prominence photographed by Young. 1870, Dec. 22 Sicilian eclipse. Young discovers reversing layer. 1871, May 11 Death of Sir J. Herschel. 1871, June 9 Line-displacements due to solar rotation detected by Vogel. 1871, Dec. 12 Total eclipse visible in India. Janssen observes reflected Fraunhofer lines in spectrum of corona. 1872 Conclusion of a three years' series of observations on lunar heat by Lord Rosse. 1872 Spectrum of Vega photographed by H. Draper. 1872 Faye's cyclonic hypothesis of sun-spots. 1872 Young's solar-spectroscopic observations at Mount Sherman. 1872 Cornu's experiments on the velocity of light. 1872, Nov. 27 Meteoric shower connected with Biela's comet. 1873 Determination of mean density of the earth by Cornu and Baille. 1873 Solar photographic work begun at Greenwich. 1873 Erection of 26-inch Washington refractor. 1874 Light-equation redetermined by Glasenapp. 1874 Vogel's classification of stellar spectra. 1874, Dec. 8 Transit of Venus. 1876 Publication of Neison's The Moon. 1876, Nov. 24 New star in Cygnus discovered by Schmidt. 1876 Spectrum of Vega photographed by Huggins. First use of dry gelatine plates in celestial photography. 1877, May 19 Klein observes a supposed new lunar crater (Hyginus N.). 1877 Measurement by Vogel of selective absorption in solar atmosphere. 1877, Aug. 16-17 Discovery of two satellites of Mars by Hall at Washington. 1877, Sept. 23 Death of Leverrier. 1877 Canals of Mars discovered by Schiaparelli. 1877 Opposition of Mars observed by Gill at Ascension. Solar parallax deduced = 8.78". 1878, January Stationary meteor-radiants described by Denning. 1878 Publication of Schmidt's Charte der Gebirge des Mondes. 1878 First observations of Great Red Spot on Jupiter. 1878 Conclusion of Newcomb's researches on the lunar theory. 1878, May 6 Transit of Mercury. 1878 Foundation of Selenographical Society. 1878, July 29 Total eclipse visible in America. Vast equatoreal extension of the corona. 1878, October Completion of Potsdam Astrophysical Observatory. 1878, Dec. 12 Lockyer's theory of celestial dissociation communicated to the Royal Society. 1879 Michelson's experiments on the velocity of light. 1879 Publication of Gould's Uranometria Argentina. 1879, November Observations of the spectra of sun-spots begun at South Kensington. 1879, Dec. 5 Abney's map of the infra-red solar spectrum presented to the Royal Society. 1879, Dec. 18 Ultra-violet spectra of white stars described by Huggins. 1879, Dec. 18 Communication of G. H. Darwin's researches into the early history of the moon. 1880, Jan. 31 Discovery at Cordoba of a great southern comet. 1880 Conditions of Algol's eclipses determined by Pickering. 1880 Pickering computes mass-brightness of binary stars. 1880, Sept. 30 Draper's photograph of the Orion nebula. 1880 The bolometer invented by Langley. 1881, Jan. 20 Communication of G. H. Darwin's researches into the effects of tidal friction on the evolution of the solar system. 1881 Langley's observations of atmospheric absorption on Mount Whitney. 1881, June 16 Perihelion of Tebbutt's comet. 1881, June 24 Its spectrum photographed by Huggins. 1881, June Photographs of Tebbutt's comet by Janssen and Draper. 1881, Aug. 15 Retirement of Sir George Airy. Succeeded by Christie. 1881, Aug. 22 Perihelion of Schaeberle's comet. 1881 Publication of Stone's Cape Catalogue for 1880. 1882 Struve's second measures of Saturn's ring-system. 1882 Newcomb's determination of the velocity of light. Resulting solar parallax = 8.79". 1882 Correction by Nyren of Struve's constant of aberration. 1882, March 7 Spectrum of Orion nebula photographed by Huggins. 1882, May 17 Total solar eclipse observed at Sohag in Egypt. 1882, May 27 Sodium-rays observed at Dunecht in spectrum of Comet Wells. 1882, June 10 Perihelion of Comet Wells. 1882, Sept. 17 Perihelion of Great Comet. Daylight detection by Common. Transit observed at the Cape. 1882, Sept. 18 Iron lines identified in spectrum by Copeland and J. G. Lohse. 1882, September Photographs of comet taken at the Cape Observatory, showing a background crowded with stars. 1882, Dec. 6 Transit of Venus. 1882 Duplication of Martian canals observed by Schiaparelli. 1882 Completion by Loewy at Paris of first equatoreal Coude. 1882 Rigidity of the earth concluded from tidal observations by G. H. Darwin. 1882 Experiments by Huggins on photographing the corona without an eclipse. 1882 Publication of Holden's Monograph of the Orion Nebula. 1883, Jan. 30 Orion Nebula photographed by Common. 1883, May 6 Caroline Island eclipse. 1883, June 1 Great comet of 1882 observed from Cordoba at a distance from the earth of 470 million miles. 1883 Parallaxes of nine southern stars measured by Gill and Elkin. 1883 Catalogue of the spectra of 4,051 stars by Vogel. 1884, Jan. 25 Return to perihelion of Pons's comet. 1884 Photometric Catalogue by Pickering of 4,260 stars. 1884 Publication of Gore's Catalogue of Variable Stars. 1884 Publication of Faye's Origine du Monde. 1884, Oct. 4 Eclipse of the moon. Heat-phases measured by Boeddicker at Parsonstown. 1884 Duner's Catalogue of Stars with Banded Spectra. 1884 Backlund's researches into the movements of Encke's comet. 1885, February Langley measures the lunar heat-spectrum. 1885 Publication of Uranometria Nova Oxoniensis. 1885, Aug. 17 New star in Andromeda nebula discerned by Gully. 1885, Sept. 5 Thollon's drawing of the solar spectrum presented to the Paris Academy. 1885, Sept. 9 Solar eclipse visible in New Zealand. 1885, Nov. 16 Photographic discovery by Paul and Prosper Henry of a nebula in the Pleiades. 1885, Nov. 27 Shower of Biela meteors. 1885 Thirty-inch achromatic mounted at Pulkowa. 1885 Publication of Rowland's photographic map of the normal solar spectrum. 1885 Bakhuyzen's determination of the rotation period of Mars. 1885 Stellar photographs by Paul and Prosper Henry. 1886, Jan. 26 Spectra of forty Pleiades simultaneously photographed at Harvard College. 1886, Feb. 5 First visual observation of the Maia nebula with the Pulkowa 30-inch refractor. 1886, March Photographs by the Henrys of the Pleiades, showing 2,326 stars with nebulae intermixed. 1886, May Photographic investigations of stellar parallax undertaken by Pritchard. 1886, May 6 Periodical changes in spectra of sun-spots announced by Lockyer. 1886, June 4 An international Photographic Congress proposed by Gill. 1886, Aug. 29 Total eclipse of the sun observed at Grenada. 1886, Oct. 1 Roberts's photograph showing annular structure of the Andromeda nebula. 1886, Dec. 8 Roberts's photograph of the Pleiades nebulosities. 1886 Solar heat-spectrum extended by Langley to below five microns. 1886, Dec. 28 Detection by Copeland of helium-ray in spectrum of the Orion nebula. 1886 Thirty-inch refractor mounted at Nice. 1886 Publication of Argentine General Catalogue. 1886 Completion of Auwers's reduction of Bradley's observations. 1886 Draper Memorial photographic work begun at Harvard College. 1886 Photographic detection at Harvard College of bright hydrogen lines in spectra of variables (Mira Ceti and U Orionis). 1887, Jan. 18 Discovery by Thome at Cordoba of a great comet belonging to the same group as the comet of 1882. 1887 Publication of Lockyer's Chemistry of the Sun. 1887, April 16 Meeting at Paris of the International Astrophotographic Congress. 1887 Heliometric triangulation of the Pleiades by Elkin. 1887 L. Struve's investigation of the sun's motion, and redetermination of the constant of precession. 1887 Von Konkoly's extension to 15 deg. S. Dec. of Vogel's spectroscopic Catalogue. 1887 Auwers's investigation of the solar diameter. 1887 Publication of Schiaparelli's Measures of Double Stars (1875-85). 1887, April 8 Death of Thollon at Nice. 1887, Aug. 19 Total eclipse of the sun. Shadow-path crossed Russia. Observations marred by bad weather. 1887, November Langley's researches on the temperature of the moon. 1887, Nov. 17 Lockyer's Researches on Meteorites communicated to the Royal Society. 1887 Completion of 36-inch Lick refractor. 1888 Kuestner's detection of variations in the latitude of Berlin brought before the International Geodetic Association. 1888 Chandler's first Catalogue of Variable Stars. 1888 Mean parallax of northern first magnitude stars determined by Elkin. 1888 Publication of Dreyer's New General Catalogue of 7,844 nebulae. 1888 Vogel's first spectrographic determinations of stellar radial motion. 1888 Carbon absorption recognised in solar spectrum by Trowbridge and Hutchins. 1888, Jan. 28 Total eclipse of the moon. Heat-phases measured at Parsonstown. 1888, Feb. 5 Remarkable photograph of the Orion nebula spectrum taken at Tulse Hill. 1888, June 1 Activity of the Lick Observatory begun. 1888 Completion of Dr. Common's 5-foot reflector. 1888 Heliometric measures of Iris for solar parallax at the Cape, Newhaven (U.S.A.), and Leipsic. 1888 Loewy describes a comparative method of determining constant of aberration. 1888 Presentation of the Dunecht instrumental outfit to the nation by Lord Crawford. Copeland succeeds Piazzi Smyth as Astronomer-Royal for Scotland. 1888, Sept. 12 Death of R. A. Proctor. 1889 Photograph of the Orion nebula taken by W. H. Pickering, showing it to be the nucleus of a vast spiral. 1889 Discovery at a Harvard College of the first-known spectroscopic doubles, Zeta Ursae Majoris and Beta Aurigae. 1889 Eclipses of Algol demonstrated spectrographically by Vogel. 1889 Completion of photographic work for the Southern Durchmusterung. 1889 Boeddicker's drawing of the Milky Way. 1889 Draper Memorial photographs of southern star-spectra taken in Peru. 1889 Pernter's experiments on scintillation from the Sonnblick. 1889 H. Struve's researches on Saturn's satellites. 1889 Harkness's investigation of the masses of Mercury, Venus, and the Earth. 1889 Heliometric measures of Victoria and Sappho at the Cape. 1889, Jan. 1 Total solar eclipse visible in California. 1889, Feb. 7 Foundation of the Astronomical Society of the Pacific. 1889, March Investigation by Sir William and Lady Huggins of the spectrum of the Orion nebula. 1889, July-Aug. First photographs of the Milky Way taken by Barnard. 1889, August 2 Observation by Barnard of four companions to Brooks's comet. 1889, Nov. 1 Passage of Japetus behind Saturn's dusky ring observed by Barnard. 1889, December Schiaparelli announces synchronous rotation and revolution of Mercury. 1889, Dec. 22 Total eclipse of the sun visible in Guiana. Death of Father Perry, December 27. 1889 Spectrum of Uranus investigated visually by Keeler, photographically by Huggins. 1890 Long-exposure photographs of ring-nebula in Lyra. 1890 Determinations of the solar translation by L. Boss and O. Stumpe. 1890 Schiaparelli finds for Venus an identical period of rotation and revolution. 1890 Publication of Thollon's map of the solar spectrum. 1890 Bigelow's mathematical theory of coronal structures. 1890 Foundation of the British Astronomical Association. 1890 Measurements by Keeler at Lick of nebular radial movements. 1890 Janssen's ascent of Mont Blanc, by which he ascertained the purely terrestrial origin of the oxygen-absorption in the solar spectrum. 1890 Newcomb's discussion of the transits of Venus of 1761 and 1769. 1890 Spiral structure of Magellanic Clouds displayed in photographs taken by H. C. Russell of Sydney. 1890 Publication of the Draper Catalogue of Stellar Spectra. 1890, April 24 Spica announced by Vogel to be a spectroscopic binary. 1890, June Gore's Catalogue of computed Binaries. 1890, November Study by Sir William and Lady Huggins of the spectra of Wolf and Rayet's stars in Cygnus. 1890, November Discovery by Barnard of a close nebulous companion to Merope in the Pleiades. 1890, November McClean Spectrographs of the High and Low Sun. 1891 Capture-theory of comets developed by Callandreau, Tisserand, and Newton. 1891 Duner's spectroscopic researches on the sun's rotation. 1891 Preponderance of Sirian stars in the Milky Way concluded by Pickering, Gill, and Kapteyn. 1891 Detection by Mrs. Fleming of spectral variations corresponding to light-changes in Beta Lyrae. 1891 Establishment of the Harvard College Station at Arequipa in Peru (height 8,000 feet). 1891 Variations of latitude investigated by Chandler. 1891 Prominence-photography set on foot by Hale at Chicago and Deslandres at Paris. 1891 Schmidt's Theory of Refraction in the Sun. 1891, April Meeting at Paris of the Permanent Committee for the Photographic Charting of the Heavens. 1891, May 9 Transit of Mercury. 1891, Aug. 19 Presidential Address by Huggins at the Cardiff Meeting of the British Association. 1891, Dec. 10 Nova Aurigae photographed at Harvard College. 1891, Dec. 20 Photographic maximum of Nova Aurigae. 1891, Dec. 22 First photographic discovery of a minor planet by Max Wolf at Heidelberg. 1892 Commencement of international photographic charting work. 1892 Photographic determination by Scheiner of 833 stars in the Hercules Cluster (M 13). 1892 Publication of Vogel's spectrographic determinations for fifty-one stars. 1892 Publication of Pritchard's photographic parallaxes. 1892, Jan. 2 Death of Sir George Airy. 1892, Jan. 21 Death of Professor Adams. 1892, Feb. 1 Announcement by Anderson of the outburst of a new star in Auriga. 1892, Feb. 5 Appearance of the largest sun-spot ever photographed at Greenwich. 1892, March Photograph of Argo nebula taken by Gill in twelve hours. 1892, March 6 Discovery of a bright comet by Swift. 1892, June 29 Death of Admiral Mouchez. Succeeded by Tisserand as director of the National Observatory, Paris. 1892, Aug. 4 Favourable Opposition of Mars. 1892, Aug. 17 Rediscovery at Lick of Nova Aurigae. 1892, Sept. 9 Discovery by Barnard of Jupiter's inner satellite. 1892, Oct. 12 First photographic discovery of a comet by Barnard. 1892, Nov. 6 Discovery of Holmes's comet. 1892, Nov. 23 Shower of Andromede meteors visible in America. 1892 Poynting's Determination of the Earth's Mean Density. 1892 Duner's Investigation of the System of upsilon Cygni. 1892 Photographic investigation by Deslandres of the spectra of prominences. 1892 Photographs of the sun with faculae and chromospheric surroundings taken by Hale with a single exposure. 1892 Investigation by T. J. J. See of the ancient colour of Sirius. 1892 Publication of T. J. J. See's Thesis on the Evolution of Binary Systems. 1892 Chandler's theory of Algol's inequalities. 1892 Nebula in Cygnus photographically discovered by Max Wolf. 1893, Jan. 28 Kapteyn's investigation of the structure of the stellar universe. 1893, March 10 Gill announces his results from the Opposition of Victoria, among them a solar parallax = 8.809". 1893, April 16 Total solar eclipse observed in South America and West Africa. 1893 Publication of Kruger's Catalog der Farbigen Sterne. 1893 Conclusion of Boys's series of Experiments on the Density of the Earth. 1893 Publication of Cordoba Durchmusterung, vol. i. 1893 Fabry shows comets to be dependents of the Solar System. 1893 Publication of Easton's Voie Lactee. 1893 Campbell detects bright H Alpha in Gamma Argus and Alcyone. 1893 Nova Normae photographed July 10; discovered on plates, October 26. 1893, May 28 Death of Professor Pritchard. 1893, July 27 Installation of 28-inch refractor at the Royal Observatory, Greenwich. 1893, December Exterior nebulosities of Pleiades photographed by Barnard. 1893, Dec. 6 Death of Rudolf Wolf. 1894, January Sun-spot maximum. 1894 Publication of Potsdam Photometric Durchmusterung, part i. 1894 Publication of Roberts's Celestial Photographs, vol. i. 1894 Wilson and Gray's determination of the sun's temperature. 1894 Barnard's micrometric measures of asteroids. 1894 McClean's gift of an astrophysical outfit to the Cape Observatory. 1894 Establishment of the Lowell Observatory at Flagstaff, Arizona. 1894 Taylor's triple achromatic objective described. 1894, April 3 Discovery of Gale's Comet. 1894 Sampson's investigation of the sun's rotation. 1894, Oct. 20 Favourable opposition of Mars. 1894, Nov. 11 Transit of Mercury. 1894, December Howlett impugns the Wilsonian theory of sun-spots. 1894, Dec. 14 Death of A. Cowper Ranyard. 1895 Publication of Newcomb's Astronomical Constants. 1895 Bailey's Photometric Catalogue of 7,922 Southern Stars. 1895 Bailey's photographic discovery of variable star clusters. 1895 Publication of E. W. Brown's Lunar Theory. 1895 Tisserand's theory of the inequalities of Algol. 1895 Stratonoff's determination of the sun's rotation from photographs of faculae. 1895 Binary character of Eta Aquilae spectroscopically recognised by Belopolsky. 1895 Presentation of the Crossley reflector to the Lick Observatory. 1895, March 23 Great nebula in Ophiuchus discovered photographically by Barnard. 1895, March 25 Ramsay's capture of Helium. 1895, April Constitution of Saturn's rings spectrographically demonstrated by Keeler. 1895 Binary character of Delta Cephei spectroscopically detected by Belopolsky. 1895, June 11 Death of Daniel Kirkwood. 1895, July 7 Death of F. W. G. Sporer. 1895, October Nova Carinae spectrographically discovered by Mrs. Fleming. 1895, Dec. 12 Nova Centauri spectrographically discovered by Mrs. Fleming. 1895, Dec. 28 Death of John Russell Hind. 1896 Gill's Report on the Geodetic Survey of South Africa. 1896 Appearance of Loewy's Photographic Atlas of the Moon, part i. 1896, January Fessenden's electrostatic theory of comets. 1896 Chandler's Third Catalogue of Variable Stars. 1896 Publication of Lick Observatory Photographic Atlas of the Moon, part i. 1896, February Effects of pressure on wave-length described by Humphreys and Mohler. 1896, April 5 Opening of new Scottish Royal Observatory on Blackford Hill, Edinburgh. 1896, April Pickering's photometric determinations of light curves of variable stars. 1896 One of the stars of Castor spectroscopically resolved into two by Belopolsky. 1896, May Third Astrographic Chart Conference at Paris. 1896, Aug. 9 Total eclipse of the sun visible in Novaya Zemlya. Reversing layer photographed by Shackleton. 1896, Aug. 30 Death of Hubert A. Newton. 1896, Sept. 18 Death of Hippolyte Fizeau. 1896, Oct. 20 Death of F. Tisserand. Succeeded by Maurice Loewy. 1896, Nov. 13 Detection by Schaeberle of Procyon's missing satellite. 1896, Nov. 26 Death of Benjamin Apthorp Gould. 1896, November Second series of hydrogen-lines discovered by Pickering in stellar spectra. 1896, December Zeeman's discovery of spectral modifications through magnetic influence. 1896, December Oxygen-absorption identified in the sun by Runge and Paschen. 1896 Study of lunar formations by Loewy and Puiseux. 1896 Mounting of the Mills spectrograph at the Lick Observatory. 1897 Installation at Greenwich of the Thompson 26-inch photographic refractor. 1897 Publication of Miss Maury's Discussion of the Photographed Spectra of 681 Stars. 1897 Callandreau's researches on cometary disaggregation. 1897 Braun's determination of the earth's mean density. 1897 Tenuity of calcium vapour in chromosphere demonstrated spectroscopically by Sir William and Lady Huggins. 1897 Completion at the Cape Observatory of McClean's spectrographic survey of the heavens. 1897 Twenty-one Wolf-Rayet stars found by Mrs. Fleming in Magellanic Cloud. 1897 Percival Lowell's New Observations on the Planet Mercury presented to the American Academy. 1897, April 8 McClean recognises oxygen-absorption in helium stars. 1897, May 9 Death of E. J. Stone, Radcliffe Observer. 1897, June 10 Death of Alvan G. Clark. 1897, June 18 Spectrum of a meteor photographed at Arequipa. 1897, Oct. 21 Inauguration of the Yerkes Observatory. 1897 Rabourdin's photographs of nebulae with the Meudon reflector. 1897 Dr. See's discoveries of Southern double stars with the Lowell 24-inch refractor. 1898, Jan. 22 Total eclipse of the sun visible in India. 1898, February Binary character of Zeta Geminorum ascertained spectroscopically by Belopolsky. 1898 Star with proper motion of nearly 9" discovered by Innes and Kapteyn from the Cape Durchmusterung plates. 1898, March 8 Nova Sagittarii photographed on Draper Memorial plates. 1898, June 20 Opening of Grand-ducal Observatory at Koenigsstuhl, Heidelberg. 1898 Keeler succeeds Holden as Director of the Lick Observatory. 1898 Bruno Peter's results in stellar parallax. 1898 Lewis Swift's discoveries of nebulae at Echo Mountain, California. 1898 Hale's photographic investigation of carbon stars. 1898, Aug. 14 Discovery of Eros by Witt. 1898 Flint's investigations of stellar parallax by meridian differences. 1898 Easton's spiral theory of the Milky Way. 1898 Seeliger's research on star distribution. 1898, October Multiple hydrogen-bands observed by Campbell in Mira Ceti. 1898, November Orbit of a Leonid meteor photographically determined by Elkin. 1899 Publication of Potsdam Photometric Durchmusterung, part ii. 1899 Innes's Reference Catalogue of Southern Double Stars. 1899 Keeler's photographs of nebulae with the Crossley reflector and generalization of their spiral character. 1899, January Spectrum of Andromeda nebula photographed by Scheiner. 1899, April Photographic discovery of Nova Aquilae by Mrs. Fleming. 1899, Aug. 26 Installation of 31-inch photographic refractor at Potsdam. 1899 Campbell's detection of Polaris as spectroscopically triple. 1899, October Duplicate discovery by Campbell and Newall of Capella as a spectroscopic binary. 1899, Nov. 15 Failure of the Leonids. Deflection of the stream predicted by Johnstone Stoney and Downing. 1899, December Publication of Sir William and Lady Huggins's Atlas of Representative Stellar Spectra. 1899 Thirty-two-inch photographic refractor mounted at Meudon. 1899 Issue of first volume of Potsdam measures of international catalogue plates. 1900, Jan. 27 Kapteyn's determination of the apex of solar motion. 1900 Chase's measures for parallax of swiftly-moving stars. 1900 Publication of Gill's Researches on Stellar Parallax. 1900 Kapteyn proposes a method for a stellar parallax Durchmusterung, and gives specimen results for 248 stars. 1900 Burnham's general catalogue of 1,290 double stars. 1900 Publication of the concluding volume of the Cape Photographic Durchmusterung. 1900, May 28 Spanish-American total eclipse of the sun. 1900, July International Conference at Paris. Co-operation arranged of fifty-eight observatories in measures of Eros for solar parallax. 1900 Horizontal refractor, of 50 inches aperture, 197 feet focus, installed in Paris Exhibition. 1900, Aug. 12 Death of Professor Keeler. Succeeded by Campbell in direction of Lick Observatory. 1900, November Opposition of Eros. 1900 Publication of Roberts's Celestial Photographs, vol. ii. 1900 Complete publication of Langley's researches on the infra-red spectrum. 1900 Printing begun of Paris section of International Photographic Catalogue. 1901, Feb. 22 Nova Persei discovered by Anderson. 1901, February Variability of Eros announced by Oppolzer. 1901, April 23 Apparition of a great comet at the Cape. 1901 Publication of Pickering's Photometric Durchmusterung. 1901 Miss Cannon's discussion of the spectra of 1,122 Southern stars. 1901 Kapteyn's investigation of mean stellar parallax. 1901 Campbell's determination of the sun's velocity. 1901 Porter's research on the solar motion in space. 1901 Bigelow's magnetic theory of the solar corona. 1901 Hussey's measurements of the Pulkowa double stars. 1901 Radial velocities of the components of Delta Equulei measured at Lick. 1901, April 16 Death of Henry A. Rowland. 1901, June Nebular spectrum derived from Nova Persei. 1901, Aug. 23 Nebula near Nova Persei photographed by Max Wolf. 1901, Sept. 20 The same exhibited in spiral form on a plate taken by Ritchey at the Yerkes Observatory. 1901, Nov. 8 Photograph taken by Perrine with the Crossley reflector showed nebula in course of rapid change. 1901, Sept. 19 Unveiling of the McClean "Victoria" telescope at the Royal Observatory, Cape of Good Hope. 1901 Sun-spot minimum.

TABLE II.

CHEMICAL ELEMENTS IN THE SUN (ROWLAND, 1891).

Arranged according to the number of their representative Lines in the Solar Spectrum.

Iron (2000+). Neodymium. Cadmium. Nickel. Lanthanum. Rhodium. Titanium. Yttrium. Erbium. Manganese. Niobium. Zinc. Chromium. Molybdenum. Copper (2). Cobalt. Palladium. Silver (2). Carbon (200+). Magnesium (20+). Glucinum (2). Vanadium. Sodium (11). Germanium. Zirconium. Silicon. Tin. Cerium. Strontium. Lead (1). Calcium (75+). Barium. Potassium (1). Scandium. Aluminium (4).

Doubtful Elements.—Iridium, osmium, platinum, ruthenium, tantalum, thorium, tungsten, uranium.

Not in Solar Spectrum.—Antimony, arsenic, bismuth, boron, nitrogen (vacuum tube), caesium, gold, iridium, mercury, phosphorus, rubidium, selenium, sulphur, thallium, praseodymium.

Oxygen was added to the solar ingredients by Runge and Paschen in 1896, gallium by Hartley and Ramage in 1899. Lithium may be admitted provisionally, and the chromospheric constituent helium takes rank, since 1895, as a chemical element.

TABLE III.

EPOCHS OF SUN-SPOT MAXIMUM AND MINIMUM FROM 1610 TO 1901.

+ + + + + + + Minima. Maxima. Minima. Maxima. Minima. Maxima. + + + + + + + 1610.8 1615.5 1712.0 1718.2 1810.6 1816.4 1619.0 1626.0 1723.5 1727.5 1823.3 1829.9 1634.0 1639.5 1734.0 1738.7 1833.9 1837.2 1645.0 1649.0 1745.0 1750.3 1843.5 1848.1 1655.0 1660.0 1755.2 1761.5 1856.0 1860.1 1666.0 1675.0 1766.5 1769.7 1867.2 1870.6 1679.5 1685.0 1775.5 1778.4 1878.9 1884.0 1689.5 1693.0 1784.7 1788.1 1890.2 1894.0 1698.9 1705.5 1798.3 1804.2 1901.9 + + + + + + +

TABLE IV.

MOVEMENTS OF SUN AND STARS.

1. Translation of Solar System.

- - Apex of Movement. Authority. Date. - - R. A. Dec. 277 deg. 30' + 35 deg. Newcomb 1898 273 deg. 36' + 29 deg. 30' Kapteyn 1901 279 deg. + 46 deg. Porter 1901 275 deg. + 45 deg. Boss 1901 277 deg. 30' + 20 deg. Campbell (from stellar 1902 spectroscopic measures) - - Velocity = 12.4 miles per second (Campbell).

2. Stellar Velocities.

+ -+ + -+ -+ Name of Star. Rate. Direction. Remarks. Miles per Sec. + -+ + -+ -+ Delta Leporis 58 Receding Campbell, 1901 Eta Cephei 54 Approaching " 1899 Theta Canis Majoris 60 Receding " 1901 Iota Pegasi 47 Approaching " " Mu Sagittarii 47 Approaching " " Eta Andromedae 52 Approaching " " Zeta Herculis 44 Approaching Belopolsky, 1893 61 Cygni 34 Approaching " " Mu Cassiopeiae 60 Approaching Campbell, 1901 1830 Groombridge 59 Approaching " " Arcturus 4.3 Approaching Keeler, 1890 Arcturus 278 Tangential Accepting Elkin's parallax of 0.024" 1830 Groombridge 150 Tangential Parallax = 0.14" Mu Cassiopeiae 113 Tangential Parallax = 0.10" (Peter) Z. C. 5^h 243 82 Tangential Parallax = 0.312" (Gill) Lacaille, 2,957 78 Tangential Parallax = 0.064" (Gill) Lacaille, 9,352 73 Tangential Parallax = 0.283" (Gill) o_2, Eridani 72 Tangential Parallax = 0.166" (Gill) Eta Eridani 61 Tangential Parallax = 0.149" (Gill) + -+ + -+ -+

TABLE V.

LIST OF GREAT TELESCOPES.

1. Reflectors A. Metallic Specula. - - Locality. Aperture in Focal Length Constructor. Remarks. Inches. in Feet. - - Birr Castle, Third Earl Parsonstown, 72 54 of Rosse, Newtonian. Ireland 1845 - - Melbourne 48 28 T. Grubb, Cassegrain. Observatory 1870 - - Third Earl Newtonian. Birr Castle 36 of Rosse, Remounted 1839 equatoreally 1876. - - William Newtonian. Royal Lassell, Presented Observatory 24 20 1846 by the Missess Greenwich Lassell to the Royal Observatory - - B. Silvered Glass Mirrors. - - Ealing, near 60 27 A. A. Common, Newtonian. London 1891 - - G. W. Richey, Can be employed Yerkes 60 25 1902 at choice as a Observatory Coude or a Cassegrain. - - National 48 Martin, 1875 Newtonian. Observatory, Remodelled for Paris spectrographic work by Deslandres in 1892. - - Meudon 39 9.7 Observatory - - Lick 36 17.5 Calver, 1879 Mounted by Observatory Common at Ealing in 1879. Sold by him to Crossley, 1885. Presented by Crossley to the Lick Observatory, 1895. - - Toulouse 32.5 16.2 Brothers Observatory Henry - - Marseilles 31.5 Foucault Observatory - - Royal 30 Common, 1897 Cassegrain. Observatory, Mounted as a Greenwich counterpoise to the Thompson equatoreal. - - Westgate- Common, The property on-Sea 30 1889 of Sir Norman Lockyer. - - Harvard H. Draper, Mounted for College 28 1870 spectrographic Observatory work,1887. - - Royal T. Grubb, Observatory, 24 1872 Edinburgh - - Daramona, Sir H. Remounted 1891. Ireland 24 10.5 Grubb, Owned by Mr. W. E. 1881 Wilson. - - Can be used as a Yerkes 23.5 7.7 Ritchey, Cassegrain, with Observatory 1901 an equivalent focal length of 38 feet. - - Harvard College 20 Common, Observatory 1890 - - Crowborough, 20 8.2 Sir H. Mounted with a Sussex Grubb, 7-inch 1885 refractor. - - 2. Refractors. - - Palais de Gautier, Mounted as a l'Optique, 49.2 197 1900 siderostat in Paris connection with a plane mirror 79 inches across. - - Yerkes 40 62 Alvan G. Observatory Clark, 1897 - - For photographic Lick A. Clark and purposes a Observatory 36 57.8 Sons, 1888 correcting lens is available, of 33 inches aperture, 47.8 feet focus. - - Mounted with a Meudon 32.5 55.2 Henrys and photographic Observatory Gautier, 1891 refractor of 24.4 inches aperture. - - Photographic. Astrophysical Steinheil and Mounted with a Observatory, 31.5 39.4 Repsold, 1899 visual refractor Potsdam 20 inches in aperture. - - Bischoffsheim Visual. Mounted Observatory, 30.3 52.6 Henrys and on Mont Gros, Nice Gautier, 1886 1,100 feet above sea level. - - Imperial A. Clark and Visual. Mounted Observatory, 30 42 Sons, 1885 by Repshold. Pulkowa - - National Observatory, 28.9 Martin Paris - - Royal Sir H. Visual and Observatory, 28 28 Grubb, photographic. Greenwich 1894 Mounted by Ransome and Simms. - - University Sir H. Grubb, Visual. Observatory, 27 34 1881 Vienna - - Royal Sir H. Grubb, The Thompson Observatory, 26 26 1897 photographic Greenwich equatoreal. - - Naval A. Clark and Observatory, 26 29 Sons, 1873 Washington - - Leander A. Clark and McCormick 26 32.5 Sons, 1881 Observatory, Virginia - - Cambridge T. Cooke and Presented to the University 25 Sons, 1870 University in Observatory 1889 by Mr. R. S. Newall. - - Meudon Henrys and Photographic. Observatory 24.4 52.2 Gautier, Mounted with a 1891 visual 32.5 refractor. - - Harvard A. Clark and Photographic College 24 11.3 Sons, 1893 doublet. The gift Observatory of Miss Bruce. Transfered in 1896 to Arequipa, Peru. - - Royal Sir H. Grubb, Photographic. Observatory, 1898 The gift or Mr. Cape of 24 22.6 McClean. Mounted Good Hope with an 18-inch visual refractor. - - Lowell Alvan G. Visual. First Observatory, Clark, 1896 mounted near the Flagstaff, 24 31 city of Mexico. Arizona Installed at Flagstaff, 1897. - - National Henrys and Visual and Observatory, 23.6 59 Gautier, photographic. Paris 1891 Mounted as an equatoreal Coude. - - Halsted A. Clark and Observatory, 23 32 Sons, 1883 Princeton, N.J. - - City Mounted as a Observatory, 22 30 visual Edinburgh equatoreal on the Calton Hill, 1898. - - Etna Merz, 1897 Observatory 21.8 - - Buckingham Buckingham Observatory 21.2 and Wragge - - Porro Porro Observatory, 20.5 Turin - - Chamberlin Alvan G. Visual. Observatory, 20 28 Clark and with a reversible Colorado Saegmueller, crown lens for 1894 photography. - - Manila Merz and Visual. Observatory 20 Saegmueller, Provided with a 1894 photographic correcting lens. - - Strasburg 20.5 23 Merz and Observatory Repsold, 1880 - - Brera Merz and Observatory, 19.1 23 Repsold Milan - - Dearborn A. Clark and Mounted 1864. Observatory, 18.5 27 Sons, 1862 Illinois - - National Henrys and Coude Mount. Observatory, 18.1 29.5 Gautier, Visual. La Plata 1890 - - Lowell Brashear, Mounted with a Observatory, 18 26.3 1894 12-inch Clark Flagstaff, refractor as Arizona counterpoise. - - Van der Zee Fitz Dismounted. Observatory, Buffalo, 18 N.Y. - - Bischoffsheim Henrys and Coude Mount. Observatory, 16.5 26.2 Gautier, Visual. Nice 1889 -= - - University Henrys and Coude Mount. Observatory, 16.5 29.5 Gautier, Visual. Vienna 1890 - - Jesuit Henrys and Photographic. Observatory, 16.5 22.5 Gautier, Mounted with a Zi-ka-Wei 1897 visual refractor of equal aperture. - - Goodsell Brashear, Observatory, 16.2 1891 Northfield, Minnesota. - - Warner A. Clark and Observatory, 16 22 Sons, 1891 Rochester, N.Y. - - Grand-Ducal Brashear and A twin Observatory, 16 6.6 Grubb, 1900 photographic Koenigsstuhl, doublet. The gift Heidelberg of Miss Bruce. Mounted with a visual 10-inch refractor by Pauly. - - Meudon Observatory 15.7 5.3 - - Washburn A. Clark and Observatory, 15.6 20.3 Sons, 1879 Wisconsin - - Teramo T. Cooke and Formerly the Observatory, 15.5 Sons, 1885 property of Italy Mr. Wigglesworth. - - Royal T. Grubb, Presented by Observatory, 15.1 1872 Lord Crawford. Edinburgh - - Madrid Merz Observatory 15 - - Tulse Hill Sir H. Grubb, Lent by the Observatory 15 15 1870 Royal Society to Sir William Huggins. Mounted with an 18-inch Cassegrain reflector. - - National Lerebours Observatory, 15 29 Paris - - Harvard Merz, 1847 College 15 22 Observatory - - National Observatory, 15 Rio de Janeiro - - Tacubaya Sir H. Grubb, Observatory, 15 15 1880 Mexico - - Stonyhurst Sir H. Grubb, College 15 15 1893 Observatory - - Brera Observatory, 15 Milan - - University Sir H. Grubb, Visual. of 15 15 1893 Mounted with a Mississippi photographic 9-inch refractor. - - Imperial Merz and Observatory, 15 22.5 Mahler, 1840 Pulkowa - - Maidenhead Sir H. Grubb, The property of Observatory 15 1893 Mr. Dunn. Mounted with a twin photographic reflector. - - Odessa Merz, 1881 Observatory 14.9 - - Bischoffsheim Henrys and Observatory, 14.9 23 Gautier Nice - - Brussels Merz and Observatory 14.9 20 Cooke, 1877 - - Observatory Merz and of Bordeaux 14.9 22.4 Gautier, 1880 - - Observatory Merz and of Lisbon 14.9 Mahler - -

TABLE VI.

List of Observatories employed in the Construction of the Photographic Chart and Catalogue of the Heavens.

All are provided with 13-inch photographic, coupled with 11-inch visual refractors:

Name of Observatory. Constructors of Instruments. - Optical Part. Mechanical Part. Paris Henrys Gautier Algiers " " Bordeaux " " Toulouse " " San Fernando (Spain) " " Vatican " " Cordoba " " Montevideo " " Perth, Western Australia " " Helsingfors " Repsold Potsdam Steinheil " Catania " Salmoiraghi Greenwich Sir H. Grubb Sir H. Grubb Oxford " " The Cape " " Melbourne " " Sydney " " Tacubaya (Mexico) " "



INDEX

Abbe, Cleveland, corona of 1878, 176, 177

Aberdour, Lord, solar chromosphere, 68

Aberration, discovered by Bradley, 3, 15; cause of, 31, 231; investigations of, 241, 438

Abney, daylight coronal photographs, 179; infra-red photography, 210, 223, 438

Absorption, terrestrial atmospheric, 134, 211, 214-216, 225; solar, 134-136, 172, 213, 221, 222, 225, 277; correlative with emission, 135, 136, 140

Adams, discovery of Neptune, 79-82; lunar acceleration, 271; orbit of November meteors, 331

Aerolites, falls of, 339, 340

Airy, solar translation, 39; observations during eclipses, 62, 64, 70; Astronomer-Royal, 79; search for Neptune, 80, 81; corona of 1851, 175; solar parallax, 227, 236; transit of Venus, 233; Mercurian halo, 235; lunar atmosphere, 264

Aitken, double star discoveries, 419

Albedo, of Mercury, 246; of Venus, 255; of Mars, 283; of minor planets, 288; of Jupiter, 290; of Saturn, 303; of Uranus, 304

Alexander, spiral nebulae, 118; observation during eclipse, 245

Algol, variability of light, 10, 390; eclipses, 390; nature of system, 391

Altitude and azimuth instrument, 120 note, 121

Amici, comet of 1843, 103

Anderson, discovery of Nova Aurigae, 396; of Nova Persei, 400

Andrews, conditions of liquefaction, 151

Angstrom, C. J., Optical Researches, 138; spark spectrum, 139; nature of photosphere, 152; solar spectroscopy, 210, 212; hydrogen in sun, 211; temperature of stars, 375

Angstrom, K., infra-red solar spectrum, 210; solar constant, 225

Arago, eclipse of 1842, 62, 64, 65; prominences, 69; polarization in comets, 103; magnetic relations of aurorae, 130; nature of photosphere, 151; meteor-systems, 329

Arai, photographs of corona of 1887, 185

Arcturus, spectrum, 373, 383; radial movement, 387

Argelander, Bonn Durchmusterung, 32, 423; solar motion, 39; centre of Milky Way, 40; comet of 1811, 100

Aristotle, description of a comet, 350

Arrhenius, light-pressure theory of comets, 348

Asten, movements of Encke's comet, 94

Asteroids, so designated by Herschel, 75

Astronomical circles, 121, 122

Astronomical physics, 7, 141, 142

Astronomical Society founded, 6; Herschel its first President, 14

Astronomy, classification, 1; popularity and progress, 5; in United States, 6; in Germany, 28; practical reform, 32; of the invisible, 42; physical, 141

Atmosphere, solar, 94, 182, 192, 221, 225; of Venus, 236, 239, 253, 254; of Mercury, 246-248; of the moon, 263, 264; of Mars, 276; of minor planets, 288

Aurorae, periodicity, 129, 162; excited by meteors, 335

Auwers, reduction of Bradley's observations, 39; system of Procyon, 42; opposition of Victoria, 238; solar parallax, 240; new star in Scorpio, 395

Babinet, nebular hypothesis, 314

Backlund, movements of Encke's comet, 94, 360

Baden-Powell, Sir George, eclipse expedition, 188

Bailey, nebulosity round Pleiades, 411; stellar photometric observations, 421; discovery of variable clusters, 436

Baily, early life and career, 59-61; observations of eclipses, 61-64; density of the earth, 60, 261

Baily's Beads, 61, 62

Bakhuyzen, rotation of Mars, 275

Ball, Sir Robert, parallaxes of stars, 36 note, 416; contacts in transits, 239

Balmer's Law, 198, 383

Barnard, micrometrical measures of Neptune, 84; of minor planets, 288; of Saturn's rings, 301; photographs of solar corona, 186, 190; transit of Mercury, 245; halo round Venus, 254; surface of Mars, 280; ellipticity of Jupiter's first satellite, 292; of Uranus, 304; discovery of inner Jovian satellite, 293, 434; red spot on Jupiter, 296; eclipse of Japetus, 300; attendants on comet of 1882, 363; on Brooks's comet, 366, 367; Swift's comet, 368; photographic discovery of a comet, 369; observations of Nova Aurigae, 398, 399; Hind's variable nebula, 403; exterior Pleiades nebulosities, 411; galactic stars, 423; photographs of Milky Way, 424, 425; cluster variables, 433; horizontal telescope, 438

Bartlett, photograph of a partial eclipse, 166

Basic lines, 206, 207

Baxendell, meteors of 1866, 331

Becker, drawings of solar spectrum, 211

Beckett, Sir E. (Lord Grimthorpe), value of solar parallax, 232

Beer and Maedler, surveys of lunar surface, 265, 267; studies of Mars, 275

Belopolsky, coronal photographs, 185; theory of corona, 191; rotation of Venus, 252; of Jupiter, 297; spectroscopic determinations of Saturn's rings, 300; spectrum of Gamma Cassiopeiae, 378; system of Castor, 389, 391; detection of variable stars as spectroscopic binaries, 391

Berberich, mass of asteroids, 287; orbit of Holmes's comet, 337

Berkowski, daguerrotype of eclipsed sun, 166

Bessel, biographical sketch, 28-30; reduction of Bradley's observations, 32; parallax of 61 Cygni, 36; disturbed motion of Sirius and Procyon, 41; trans-Uranian planet, 79; Halley's comet, 102; theory of instrumental errors, 122; personal equation, 123; rotation of Mercury, 246; lunar atmosphere, 263; cometary emanations, 325, 345; multiple tails, 347; comet of 1807, 352

Betelgeux, remoteness, 37, 417; spectrum, 373, 381, 383, 384; radial movement, 387

Bianchini, rotation of Venus, 250

Biela, discovery of a comet, 95

Bigelow, magnetic and solar disturbances, 161; theory of corona, 191

Bigourdan, eclipse of 1893, 187; velocity of comet of 1882, 364

Bird's quadrants, 4, 112, 121

Birmingham, colours of stars, 375 note; discovery of T Coronae, 393

Birt, rotation of a sun-spot, 144; Selenographical Society, 266

Bischoffsheim, Coude telescope, 436

Black Ligament, 235

Bode, popular writings, 5; solar constitution, 57; missing planet, 72, 73

Bode's Law, 71, 83, 286

Boeddicker, heat-phases during lunar eclipses, 269, 270; drawings of Jupiter, 296; of the Milky Way, 424

Boehm, solar observations, 146, 148

Boguslawski, centre of sidereal revolutions, 41; observation of Halley's comet, 102

Bolometer, principle of construction, 222

Bond, G. P., his father's successor, 86; light of Jupiter, 289; Saturn's rings, 298; Donati's comet, 324, 325; Andromeda nebula, 409; double-star photography, 409

Bond, W. C., observation of Neptune's satellite, 84; discovery of Hyperion, 85; of Saturn's dusky ring, 86; resolution of nebulae, 119; celestial photography, 153, 409; satellite-transit on Jupiter, 291

Borda, repeating circle, 121

Boss, solar translation, 40; observations on comets, 352, 356

Bossert, proper motions of stars, 415

Bouguer, solar atmospheric absorption, 221

Boulliaud, period of Mira, 10

Bouvard, tables of Uranus, 78; Encke's comet, 90

Boys, radio-micrometer, 220; density of the earth, 261

Bradley, discoveries of aberration and nutation, 3; solar translation, 10; star-distances, 10, 16; observation on Castor, 17; instruments, 28, 120; observations reduced by Bessel and Auwers, 32, 39

Brahe, Tycho, star of 1572, 24

Brandes, observations of meteors, 327, 334;

Braun, prominence photography, 197; density of the earth, 261

Brayley, meteoric origin of planets, 311

Bredikhine, theory of cometary appendages, 100, 348; repulsive forces, 346, 347; chemical differences, 347, 348; formative types, 351, 352, 355, 363, 369; structure of chromosphere, 199; red spot on Jupiter, 294; Andromede meteors, 337; stationary radiants, 341; spectrum of Coggia's comet, 343

Bremiker, star maps, 81

Brenner, rotation of Venus, 252

Brester, Theorie du Soleil, 152

Brewster, diffraction theory of corona, 67; telluric lines in solar spectrum, 134; absorption spectra, 136

Brinkley, ostensible stellar parallaxes, 33

Brisbane, establishment of Paramatta Observatory, 6, 90

Brooks, fragment of 1882 comet, 363; cometary discoveries, 365, 366

Bruennow, stellar parallaxes, 113, 416

Bruno, Giordano, motion of stars, 9

Buffham, rotation of Uranus, 303

Buffon, internal heat of Jupiter, 289

Bunsen, discovery of spectrum analysis, 132

Burchell, magnitude of Eta Carinae, 48

Burnham, stellar orbits, 46; coronal photographs, 186; measures of Nova Aurigae, 399; of planetary nebulae, 404; discoveries of double stars, 418, 430, 433, 435; catalogue, 419; system of 61 Cygni, 419

Burton, canals of Mars, 279; rotation of Jupiter's satellites, 292

Calandrelli, stellar parallaxes, 33

Callandreau, capture theory of comets, 98

Campani, Saturn's dusky ring, 86

Campbell, Lieutenant, polarisation of corona, 170

Campbell, Professor, stellar radial velocities, 39, 406, 434; flash spectrum, 189; spectroscopic observations of Saturn's rings, 300; Wolf-Rayet stars, 380; spectroscopic binaries, 389; Nova Aurigae, 398; translation of solar system, 406; stellar diffraction-spectra, 440

Canals of Mars, 278-280

Cannon, Miss A. J., spectrographic researches, 386

Canopus, remoteness, 37, 417; spectrum, 416

Capella, spectrum, 373, 383, 384; a spectroscopic binary, 389

Carbon, material of photosphere, 152; absorption by, in sun, 212; in stars, 374

Carbonelle, origin of meteorites, 340

Carinae, Eta, light variation, 48, 49; spectrum, 379

Carrington, astronomical career, 144, 145; sun-spot observations, 146; solar rotation, 147; spot-distribution, 148; luminous outburst on sun, 159, 160; Jovian and sun-spot periods, 163; origin of comets, 370

Cassini, Domenico, discoveries of Saturnian satellites, 84; of division in ring, 85; solar rotation period, 146; solar parallax, 228; rotation of Venus, 250; of Mars, 274; of Jupiter, 290, 295; satellite of Venus, 256; satellite-transit on Jupiter, 291

Cassini, J. J., stellar proper motions, 10; sun-spots on limb, 54; theory of corona, 66; rotation of Venus, 250; structure of Saturn's rings, 299

Castor, system of, 18, 389

Cavendish experiment, 60, 261

Ceres, discovery, 73, 74; diameter, 75, 288

Chacornac, observation of sun-spot, 156; star-maps, 284, 413; variable nebula, 403

Challis, search for Neptune, 81, 82; duplication of Biela's comet, 96

Charlois, discoveries of minor planets, 283

Charroppin, coronal photographs, 186

Chase, photographic discovery of a comet, 338; stellar parallaxes, 416

Chladni, origin of meteors, 327, 332

Christie, Mercurian halo, 245

Chromosphere, early indications, 68; distinct recognition, 69, 70, 167; depth, 174, 175, 200; metallic injections, 195; eruptive character, 199; spectrum, 200

Clark, Alvan, large refractors, 114, 429, 430, 436

Clark, Alvan G., discovery of Sirian companion, 42, 430; 40-inch refractor, 433

Clarke, Colonel, figure of the earth, 262

Clarke, F. W., celestial dissociation, 206

Clausen, period of 1843 comet, 105; cometary systems, 362

Clerihew, secondary tail of 1843 comet, 103

Clusters, variable stars in, 436

Coggia, discovery of a comet, 343

Comet, Halley's, return in 1759, 4, 88; orbit computed by Bessel, 29; capture by Neptune, 98, 365; return in 1835, 101-103, 345; type of tail, 346, 352; of 1843, 7, 103-105; type of tail, 346, 352; relationships, 349-351; Newton's, 88, 364; Encke's, 90; changes of volume, 92; of brightness, 95; acceleration, 93, 94; capture by Mercury, 99; Winnecke's, 94, 342; Biela's, 95-97, 333; Brorsen's, 97; Vico's, 97, 367; Faye's, 98; of 1811, 99-101, 346; of 1807, 100, 347, 352; of 1819, 101, 103; Lexell's, 106, 367; Tewfik, 178, 358, 362, 369; Donati's, 323-325, 347, 348; of 1861, 326, 327, 346; Perseid, 327, 332; Leonid, 327, 332, 333, 343; Klinkerfues's, 335; Holmes's, 337, 343, 369; Coggia's, 343, 346, 347; of 1901, 343; of 1880, 349, 351; Aristotle's, 350; Tebbutt's, 352-355; Schaeberle's, 355, 356; Wells's, 356, 357; of September, 1882, 358-361, 362-364; Thome's, 361; Pons-Brooks, 365, 366; Sawerthal's, 366; Brooks's, of 1889, 366, 367; Swift's, 368

Cometary tails, repulsive action upon, 100, 103, 104, 346-348; coruscations in, 105; three types, 346-348, 355, 363; multiple, 347, 348, 351, 352, 355, 363, 368

Comets, subject to gravitation, 88; of short period, 92, 93; translucency, 95, 105, 106, 353; small masses, 96, 106; capture by planets, 98, 306, 367; changes of volume, 102, 365, 369; polarisation of light, 103, 354, 355; refractive inertness, 106, 353; relations to meteor-systems, 327, 332-336; disintegration, 333, 339, 362, 363; spectra, 342-344, 354, 355, 362-364; luminous by electricity, 344, 355, 357; systems, 353, 355, 357, 362, 365; origin, 369-371

Common, reflectors for eclipse photography, 187; Jupiter's inner satellite, 293; detection of great comet near the sun, 358; its five nuclei, 362; photographs of Andromeda nebula, 395; of Orion nebula and Jupiter, 407, 408; great reflectors, 412, 429; cluster variables, 436

Common, Miss, drawing of eclipsed sun, 187

Comstock, lunar atmosphere, 264

Comte, celestial chemistry, 140; astronomy, 142

Cooke, 25-inch refractor, 430

Copeland, comets of 1843 and 1880, 349; spectrum of comet of 1882, 364; of Gamma Cassiopeiae, 378; of Nova Andromedae, 395; of Orion nebula, 407; discoveries of gaseous stars, 379; Nova Aurigae, 396, 398

Copernicus, stellar parallax, 16

Cornu, telluric lines in solar spectrum, 202; velocities in prominences, 205; ultra-violet solar spectrum, 210, 215; velocity of light, 232 note, 241; spectrum of hydrogen, 383; of Nova Cygni, 393

Cornu and Bailie, density of the earth, 261

Corona of 1842, 62-64, 67; early records and theories, 65-67; photographs, 166, 173, 178, 181, 185-190; spectrum, 170, 173, 178, 188, 190, 193; varying types, 174-176, 193; of 1877, 175-177; of 1882, 177; of 1869, 183; of 1886, 185; of 1889, 185-187; of 1893, 188; of 1898, 189; of 1900, 189; of 1901, 190; daylight photography of, 178-180; glare theory, 182; mechanical theory, 191; electro-magnetic theories, 191, 192

Coronium, 171, 174, 193

Cortie, movements in sun-spots, 157; their spectral changes, 208

Cotes, corona of 1715, 176

Croll, secular changes of climate, 259, 260; derivation of solar energy, 313

Crookes, chemical elements, 210

Crova, solar constant, 225

Cruls, comet of 1882, 358, 364

Cusa, solar constitution, 57

Cysatus, Orion nebula, 21; comet of 1618, 362

Damoiseau, theory of Halley's comet, 101

D'Arrest, orbits of minor planets, 285; Andromede meteors, 334; ages of stars, 375; variable nebulae, 403; measures of nebulae, 404

Darwin, G. H., rigidity of the earth, 258; Saturn's ring system, 301; origin of the moon, 316-318; development of solar system, 318, 319, 322; solar tidal friction, 319

Daubree, falls of aerolites, 339

Davidson, satellite-transit on Jupiter, 292

Davis, stellar parallaxes, 417

Dawes, prominences in 1851, 70; Saturn's dusky ring, 86; a star behind a comet, 106; solar observations, 143, 164; observations and drawings of Mars, 276, 278, 280; satellite-transits on Jupiter, 291, 292

De Ball, markings on Mercury, 248

Delambre, Greenwich observations, 3; solar rotation, 146; light-equation, 231

De la Roche, Newton's law of cooling, 217

De la Rue, celestial photography, 152, 153, 268; solar investigations, 154; expedition to Spain, 166, 167

De la Tour, experiments on liquefaction, 151

Delaunay, tidal friction, 271, 272; Coude telescope, 436

Delisle, diffraction theory of corona, 67; transits of Venus, 233, 239

Dembowski, double star measurements, 418

Denning, observations of Mercury, 246, 247; mountain on Venus, 253; rotation of Jupiter, 290; red spot, 295; periodicity of markings, 297; rotation of Saturn, 302; meteors of 1885, 336; of 1892, 338; stationary radiants, 341

Denza, meteors of 1872, 334

Derham, theory of sun-spots, 53; ashen light on Venus, 255

Deslandres, eclipse expedition, 187; rotation of corona, 188; prominence photography, 198; hydrogen spectrum in prominences, 198, 383; photographs of Jupiter, 297; radial movements of Saturn's rings, 300; helium absorption in stars, 376; stellar radial velocities, 406

Diffraction, corona explained by, 67, 70, 181; spectrum, 139, 210, 223, 439

Dissociation in the sun, 152, 206-210; in space, 312

Doberck, orbits of double stars, 38, 418

Dollond, discovery of achromatic telescope, 4, 112

Donati, discovery of comet, 323; spectra of comets, 342; of stars, 372

Doppler, effect of motion on light, 200

Douglass, observations of Jupiter's satellites, 292

Downing, perturbations of the Leonids, 338

Draper, H., ultra-violet spectrum, 210; oxygen in sun, 213; photographs of the moon, 268; of Jupiter's spectrum, 291; of Tebbutt's comet, 354; of spectrum of Vega, 382; of Orion nebula 407

Draper, J. W., lunar photographs, 152; distribution of energy in spectrum, 223 note

Draper Memorial, 384-386

Dreyer, Catalogue of Nebulae, 50

Dulong and Petit, law of radiation, 217, 219

Duner, spectra of sun-spots, 156; spectroscopic measurement of solar rotation, 203; spectroscopic star catalogue, 381

Dunkin, solar translation, 39

Duponchel, sun-spot period, 163

Durchmusterung, Bonn, 33, 412; Cape photographic, 412; parallax, 418; photometric, 421

Dyson, coronal photographs, 190

Earth, mean density, 60, 261; knowledge regarding, 257; rigidity, 257, 259; variation of latitude, 258, 259; figure, 261, 262; effects of tidal friction, 271-273; bodily tides, 316; primitive disruption, 317

Easton, structure of Milky Way, 423, 424

Ebert, coronoidal discharges, 192

Eclipse, solar, of 1836, 61; of 1842, 62-65, 67, 69; of 1851, 69, 70, 166; of 1860, 166, 167; of 1868, 167-170; of 1869, 170; of 1870, 171; of 1871, 173; of 1878, 174-177; of 1882, 177, 178; of 1883, 180, 181; of 1885, 183; of 1886, 184; of 1887, 185; of 1889, 185-187; of 1893, 187, 188; of 1896, 188; of 1898, 189; of 1900, 189, 190; of 1901, 190

Eclipses, lunar, heat-phases during, 269, 270

Eclipses, solar, importance, 59; ancient, 60, 273; classification, 61; results, 192, 193

Eddie, comet of 1880, 349; of 1882, 363

Edison, tasimeter, 177

Egoroff, telluric lines in solar spectrum, 211, 214

Elements, chemical, dissociation in sun, 206, 209, 210

Elkin, star parallaxes, 37, 416, 417; photography of meteors, 338; transit of great comet, 358, 360; secondary tail, 363; triangulation of the Pleiades, 410

Elliot, opinions regarding the sun, 57

Elvins, red spot on Jupiter, 296

Encke, star maps, 78; calculation of short-period comet, 90; resisting medium, 93; distance of the sun, 230, 232; period of Pons's comet, 365

Engelmann, rotation of Jupiter's satellites, 292

Ericsson, solar temperature, 218

Erman, meteoric rings, 330

Eros, measures of, for solar parallax, 238; discovery, 284; variability, 285

Ertborn, mountain in Venus, 253

Espin, spectra of variable stars, 379; stars with banded spectra, 381; Nova Aurigae, 397, 398

Euler, resisting medium, 93

Evershed, eclipse photographs, 189, 200

Evolution, of solar system, 308, 309, 313-316, 322; of earth-moon system, 316-318; of stellar systems, 420

Fabricius, David, discovery of Mira Ceti, 10

Fabricius, John, detection of sun-spots, 52

Faculae, relation to spots, 53, 155, 158; solar rotation from, 155; photographed, 197, 198, 377

Faye, nature of prominences, 70, 166; discovery of a comet, 98; cyclonic theory of sun-spots, 144, 157; solar constitution, 150-152; maximum of 1883, 163; velocities in prominences, 205; distance of the sun, 240; planetary evolution, 314, 315, 321

Feilitsch, solar appendages, 70

Fenyi, solar observations, 184, 204

Ferrel, tidal friction, 272

Ferrer, nature of corona, 67; prominences, 69

Fessenden, electrical theory of comets, 348

Finlay, transit of great comet, 358, 360

Fizeau, daguerrotype of the sun, 153; Doppler's principle, 201; velocity of light, 232

Flammarion, canals of Mars, 280; trans-Neptunian planet, 306

Flamsteed, solar constitution, 57; distance, 228

Flaugergues, detection of 1811 comet, 99; transit of Mercury, 244

Fleming, Mrs., spectrum of Beta Lyrae, 379; preparation of Draper Catalogue, 386; discoveries of new stars, 399

Flint, star-parallaxes, 417

Fontana, mountains of Venus, 252; satellite, 256; spots on Mars, 274

Forbes, George, trans-Neptunian planets, 306, 307

Forbes, James D., spectrum of annularly eclipsed sun, 134; solar constant, 225

Foucault, spectrum of voltaic arc, 137; photograph of the sun, 153; velocity of light, 232, 240; silvered glass reflectors, 429

Fraunhofer, early accident, 33; improvement of refractors, 34; clockwork motion, 121; spectra of flames, 131; of sun and stars, 133, 134, 372; objective prism, 385; diffraction gratings, 439

Fraunhofer lines, mapped, 133, 136; origin, 135-137, 171, 172; reflected in coronal spectrum, 170, 173, 181; in cometary spectra, 354, 357; shifted by radial motion, 201

Freycinet, distribution of minor planets, 287

Fritz, auroral periodicity, 162

Frost, solar heat radiation, 222

Galileo, descriptive astronomy, 2; double-star method of parallaxes, 16; discovery of sun-spots, 52; solar rotation, 146; planets and sun-spots, 163; darkening at sun's edge, 221

Galle, discovery of Neptune, 81, 82; Saturn's dusky ring, 86; distance of the sun, 237; path of Andromede meteors, 334

Galloway, solar translation, 39

Gambart, discovery of comet, 95

Gauss, orbits of minor planets, 74; Theoria Motus, 77; magnetic observations, 126, 127; cometary orbits, 370

Gautier, sun-spot and magnetic periods, 126, 128; sun-spots and weather, 129

German Astronomical Society, 6, 414

Gill, star-parallaxes, 37, 42, 416, 417; expedition to Ascension, 237; distance of the sun, 237, 238, 240; constant of aberration, 241; arc measurements, 261, 262; comet of 1882, 359, 412; oxygen-absorption in stars, 384; photograph of Argo nebula, 404; Cape Durchmusterung, 412; photographic celestial survey, 413; actinic intensity of galactic stars, 425; Coude telescope, 438

Gladstone, J. H., spectrum analysis, 134, 136

Glaisher, occultation by Halley's comet, 106

Glasenapp, coronal photographs, 185; light equation, 231, 241; double star measures, 419

Glass, optical, excise duty on, 112, 115; Guinand's, 113, 114; Jena, 431

Gledhill, spot on Jupiter, 294

Goldschmidt, nebulae in the Pleiades, 411

Goodricke, periodicity of Algol, 390

Gore, catalogue of variable stars, 391; of computed binaries, 418

Gothard, bright-line stellar spectra, 378, 379; spectrum of Nova Aurigae, 398; photographs of nebulae, 409

Gould, variation of latitude, 258; photograph of Mars, 281; comets of 1807 and 1881, 349, 352; luminous instability of stars, 392; photographic measures of the Pleiades, 410; Uranometria Argentina, 415; solar cluster, 423, 426

Graham, discovery of Metis, 77

Grant, solar envelope, 70, 167; transit phenomena, 254

Green, observation of Mars, 280

Greenwich observations, 3, 27, 32

Gregory, David, achromatic lenses, 112 note

Gregory, James, double star method of parallaxes, 16; reflecting telescopes, 109

Groombridge, star catalogue, 31

Grosch, corona of 1867, 176

Grubb, Sir Howard, photographic reflector, 409; great refractors, 430, 433; siderostat, 437

Grubb, Thomas, Melbourne reflector, 110 note, 428

Gruithuisen, snow-caps of Venus, 255; lunar inhabitants, 265

Gully, detection of Nova Andromedae, 394

Guthrie, nebulous glow round Venus, 253

Hadley, Saturn's dusky ring, 86; reflecting telescope, 109

Haerdtl, Winnecke's comet, 94

Hale, luminous outburst on sun, 161; daylight coronal photography, 179; spectrum of prominences, 195, 198; prominence photography, 197, 198; photographs of faculae, 198, 377; carbon in chromosphere, 200; bright lines in fourth-type stars, 381; reflectors and refractors, 432

Hall, Asaph, parallax of the sun, 241; discovery of Martian satellites, 282; rotation of Saturn, 302; double star measurements, 419

Hall, Chester More, invention of achromatic telescope, 112

Hall, Maxwell, rotation of Neptune, 305

Halley, stellar proper motions, 9; composition of nebulae, 22; observation of Eta Carinae, 48; eclipse of 1715, 66, 68; predicted return of comet, 88; magnetic theory of aurorae, 130; transits of Venus, 233; lunar acceleration, 271; origin of meteors, 327

Halm, magnetic relations of latitude variation, 259

Hansen, solar parallax from lunar theory, 230

Hansky, coronal photographs, 188, 189

Harding, discovery of Juno, 75; celestial atlas, 77

Harkness, spectrum of corona, 170; corona of 1878, 175; shadow of the moon in solar eclipses, 182; light equation, 231; distance of the sun, 237, 240, 241, 242

Harriot, observations on Halley's comet, 29

Hartley, gallium in the sun, 200, 213

Hartwig, Nova Andromedae, 394

Hasselberg, metallic spectra, 211; spectra of comets, 342, 357; of Nova Andromedae, 395

Hastings, composition of photosphere, 152; observations at Caroline Island, 181; Saturn's dusky ring, 299

Hegel, number of the planets, 73

Heis, radiant of Andromedes, 334

Heliometer, 34, 234, 237, 238, 240

Helium, a constituent of prominences, 194, 195, 199; no absorption by, in solar spectrum, 213; absorptive action in first-type stars, 376; bright in gaseous stars, 377, 378, 380; in Orion nebula, 407

Helmholtz, gravitational theory of sun-heat, 311-313

Hencke, discoveries of minor planets, 76

Henderson, parallax of Alpha Centauri, 36, 416; observation of chromosphere, 68

Henry, Paul and Prosper, lunar twilight, 264; markings on Uranus, 303; photograph of Saturn, 408; photographs of nebulae in the Pleiades, 410, 411; stellar photography, 413; plane mirrors, 438

Herrick and Bradley, duplication of Biela's comet, 96

Herschel, Alexander S., cometary and meteoric orbits, 332

Herschel, Caroline, her brother's assistant, 12; observation of Encke's comet, 90

Herschel, Colonel, spectrum of prominences, 168; of reversing layer, 172; of corona, 174

Herschel, Sir John, life and work, 45-50; Magellanic clouds, 47, 422; sun-spots, 58, 59, 144; solar flames, 68; anticipation of Neptune's discovery, 81; status of Hyperion, 85; Biela's comet, 95; Halley's, 102; comet of 1843, 103; sixth star in "trapezium," 113; grinding of specula, 116; spectrum analysis, 136; solar photography, 145, 154; solar constitution, 151; shadow round eclipsed sun, 182; actinometrical experiments, 216; solar heat, 217; climate and eccentricity, 259; lunar atmosphere, 263; surface of Mars, 276; Andromeda nebula, 396; observations of nebulae, 404; double nebulae, 412

Herschel, Sir William, discovery of Uranus, 5; founder of sidereal astronomy, 9; biographical sketch, 11-14; sun's motion in space, 15, 39, 425; revolutions of double stars, 18, 442; structure of Milky Way, 19-21, 423; nature of nebulae, 21-26, 401; results of his observations, 25; centre of sidereal system, 40; theory of the sun, 54-56, 70; asteroids, 75; discoveries of Saturnian and Uranian satellites, 84, 87, 110; comet of 1811, 99; reflecting telescopes, 109-111; sun-spots and weather, 129; transit of Mercury, 244; refraction in Venus, 252; lunar volcanoes, 266; terrestrial affinity of Mars, 274; Jovian trade-winds, 289; rotation of Jupiter's satellites, 292; ring of Saturn, 298; rotation of Saturn, 302; origin of comets, 369; stellar photometry, 420

Herz, comets' tails, 348

Hevelius, "Mira" Ceti, 10; contraction of comets, 92; granular structure of comet, 362

Higgs, photographs of solar spectrum, 211, 214

Hind, solar flames, 70; Iris and Flora discovered by, 77; distortion of Biela's comet, 96; transit of a comet, 101; earth in a comet's tail, 326; comets of 1843 and 1880, 349; Schmidt's comet, 363; new star, 392; variable nebula, 403

Hirn, solar temperature, 220; resistance in space, 348

Hodgson, outburst on the sun, 160

Hoeffler, star-drift in Ursa Major, 426

Hoek, cometary systems, 362

Holden, Uranian satellites, 87; eclipse expedition, 180; coronal extensions, 186; solar rotation, 203; transit of Mercury, 245; intra-Mercurian planets, 250; drawing of Venus, 252; lunar photographs, 268; canals on Mars, 279; surface of Mars, 281; transits of Jupiter's satellites, 292; markings on Uranus, 304; disintegration of comet, 362; colours of double stars, 374; Nova Aurigae, 398; Orion and Trifid nebulae, 403, 404; director of Lick Observatory, 435

Holden and Schaeberle, observations of nebulae, 433

Holmes, discovery of a comet, 337

Homann, solar translation, 406

Hooke, solar translation, 10; stellar parallax, 16; repulsive action on comets, 102 note; automatic movement of telescopes, 120; spots on Mars, 274, 275

Hopkins, solidity of the earth, 257

Horrebow, sun-spot periodicity, 125; satellite of Venus, 256

Hough, G. W., red spot on Jupiter, 295, 430; observations of double stars, 419

Houzeau, solar parallax, 240

Howlett, sun-spot observations, 155

Hubbard, period of comet of 1843, 105, 351

Huggins, Sir William, spectroscopic observations of prominences, 170, 195; hydrogen spectrum in stars, 178, 198; daylight coronal photography, 178, 179; repulsive action in corona, 191; stellar motions in line of sight, 201, 386, 387; transit of Mercury, 245; occultation of a star, 263; snowcaps on Mars, 276; spectrum of Mars, 277; of Jupiter, 290; Jovian markings and sun-spots, 297; spectrum of Uranus, 304; of comets, 342, 343; photographs, 354, 357; stellar spectroscopy, 373; colours of stars, 374; classification of star spectra, 376; photographs, 382, 383, 438; stellar chemistry, 381, 382; spectra of new stars, 393, 395; theory of Nova Aurigae, 397; spectra of nebulae, 401, 402, 407; nebular radial movement, 405

Huggins, Sir William and Lady, photograph of Uranian spectrum, 305; spectra of Wolf-Rayet stars, 380; ultra-violet spectrum of Sirius, 383; nitrogen in stars, 384; spectrum of Nova Aurigae, 396-398; of Andromeda nebula, 403; of Orion nebula, 407

Humboldt, sun-spot period, 126; magnetic observations, 127; meteoric shower, 329

Hussey, T. J., search for Neptune, 79

Hussey, W. J., cloud effects on Mars, 281; cometary appendages, 369; period of Delta Equulei, 419; discoveries of double stars, 419, 433

Huygens, stellar parallax, 16; Orion nebula, 22; discovery of Titan, 84; Saturn's ring, 85, 301; spot on Mars, 275

Hydrogen, a constituent of prominences, 168, 195, 199; spectrum, 178, 198, 383, 384; absorption in stars, 198, 373, 381-383; in sun, 211; theoretical material of comets' tails, 347; emissions in stars, 377-380, 384, 393, 397; in nebulae, 402, 407

Innes, Southern double stars, 419

Jacoby, measurement of Rutherfurd's plates, 410; Pritchard's parallax work, 417

Janssen, photographs of the sun, 165; spectroscopic observations of prominences, 168, 169; escape from Paris in a balloon, 171; coronal spectrum, 173, 181; coronal photographs, 181; rarefaction of chromospheric gases, 182; oxygen absorption in solar spectrum, 214; transit of 1874, 234; spectrum of Venus, 254; of Saturn, 303; photographs of Tebbutt's comet, 353, 354; of Orion nebula, 407

Japetus, eclipse of, 300; variability in light, 302

Jewell, solar spectroscopy, 200, 211

Joule, heat and motion, 309

Jupiter, mass corrected, 77, 92; conjectured influence on sun-spot development, 163; physical condition, 289, 290; spectrum, 290, 291; satellite-transits, 291, 292; discovery of inner satellite, 293; red spot, 293-296; photographs, 297, 408; periodicity of markings, 297

Kaiser, rotation of Mars, 275; map of Mars, 278

Kammermann, observation of Maia nebula, 410

Kant, status of nebulae, 14; Sirius the central sun, 40; planetary intervals, 71; tidal friction, 272; condition of Jupiter, 289; cosmogony, 308

Kapteyn, solar translation, 40; Cape Durchmusterung, 412; stellar parallaxes, 417, 418; actinic intensity of galactic stars, 425; solar cluster, 426

Kayser and Runge, spectroscopic investigations, 211, 213

Keeler, red spot on Jupiter, 296; spectroscopic determination of movements in Saturn's rings, 300; spectrum of Uranus, 304; of third type stars, 382; of nebulae, 402; photographs of nebulae, 403, 411, 412, 432; nebular radial movements, 405, 434, 440; grating spectroscope, 440

Kepler, star of 1604, 25; solar corona, 66; missing planets, 71; cometary decay, 91, 339; comet of 1618, 96; physical astronomy, 141

Kiaer, comets' tails, 348

Kirchhoff, foundation of spectrum analysis, 132, 135-137, 372; map of solar spectrum, 137; solar constitution, 149, 151, 172