622 BIBLIOGRAPHY OF HERSCHEL^S WRITINGS. 



Subject-Index. Philosophical Transactioks. Year. Page. 



Uranus: is round 1783 11 



: diameter (about 4') 1783 13 



: lias no ring ; and it is flattened at tlie poles 1798 70 



: certainly lias more than two satellites 1817 302 



Uranus' satellites : four new ones discovered 1798 47 



: the system of six satellites explained 1798 66 



: vanish near the planet 1798 76 



: observations 1815 293 



: observations from 1787, January 11, to 1810, May 25 1815 304 



: were discovered with a magnifying power of 157 1817 298 



Variable stars : Mira Ceti 1780 338 



: perhaps 34 Cygni has a period of 18 vears < 



i i- ^^ ^ ' < 1796 457 



: a Herculis is a periodical star 1796 452 



: have dark spots on their surface 1796 455 



: may have a proper motion 1805 236 



Venus' diameter at distance one, is 18' '.79 1793 217 



Venus : in general 1793 201 



: rotates and has an atmosphere 1793 201-2 



: its mountains ? 1793 202 



: observations from 1777, April 17, to 1793, May 20 1793 203 



: drawing 1793 204 



: is suddenly much brighter round the limb 1793 218 



: its unilluminated half has been seen 1795 51 



260 



266 



Volcanoes : observed in the moon 1787 230 



Vesta : observations 1807 



r 310 

 Wheat : its price is connected with changes in the sun 1801 < to 



( 318 



Wilson : has shown the possibility of a solar motion 1806 235 



: 1808 161 



: 1783 283 



Zodiacal light : 1811 311 



Zone catalogues made : 1795 396 



