BIBLIOGRAPHY OF HERSCHEL'S WRITINGS. 619 



Subject-Index. rniLosorFiicAL TuAXt^AcriONS. Tear. Page. 



Section of ovir sidereal system 1785 253 



Separating i^ower : sec Aperture. 



Sequences : of stellar brightness 1796 173 



: description of Herschel's metliod for stars 179() 181 



Short: 1792 9 



Sirius : effect of the Sun's attraction on Siritifi IdOG 227 



Solar eclipses : see Sun (eclipses. ) 



Solar phenomena : exxilaiued 1801 303 



Sources of error considered : see Errors. 



Space-penetrating power : of telescopes 1800 49 



: , 1817 319 



Spectra of stars : 1814 264 



: see Stars. 



Spectrum : distribution of the light and heat in the spectrum .shown by 



curves 1800 439 



Spectrum (atmospheric) of stars 1805 43 



Spectrum of the Sun: in its relations to Heat. See Heat. 



Speculum: dimensions of the 40-foot 1~95 403 



Spots on Mars, Jupiter, etc. : see Mars, Jupiter, etc. 



Spurious diameters : of stars 1803 345 



Spurious disks : in general 1805 31 



: of celestial and terrestrial objects 1805 40 



: criterion as to whether a disk is real or spurious 1805 53 



Square-shouldered aspect of Saturn 1805 272 



: 1806 462 



Star-gauges : results given in part 1784 446 



i 220 

 : results given - 1785 < to 



( 240 



: (unpublished) 1817 325 



Star-gauging : defined 1784 445 



Stars of the first magnitude : eleven pairs of them are 60° apart 1796 166 



Stars and nebulae : their connection or disjunction 1791 74-77 



: their connection 1814 249 



Stars : their parallax 1782 82 



: parallax ; method proposed 1782 87 



: some stars seen best with high powers, and some with lower 1782 92 



„ C 93 

 : drawings of a Lyra; with various powers 1782 2 



: double stars known in 1782 1782 97,98 



r 100 



: classes of double stars 1^82 < to 



( 103 



: may lose light in space 1 ' 8"- 104 



: theory of the parallax of double stars 1782 104 



: very small stars usually red 1'8"~' 140 



: their diameters ; a Lyrw's was 0".35 1782 147 



: drawing of a GemMiorH»tt ^'^'-^ 1^^ 



: lost smce Flamsteed 1^83 2o0 



: changed in brightness since Flamsteed 1783 254 



: newly come to be visible l''^'^ 2^'' 



. , ^ 1783 257 



■ ^® .■;■ 1783 259 



: variable 



. sujreestion of a method for determining the stellar system to which 



• oo 178'i '^7 



a given star belongs - 



