Modern Astronomy: Being Some Account of the Revolution of the Last Quarter of a Century

accuracy accurate actual advantage Airy almucantar already altazimuth Astro Astronomer Royal axis brightness camera century changes circle Coelostat colours comets considerable corona David Gill detect direction disc discovery double stars drawing dry-plate E. E. Barnard Earth eclipse electric equatorial Eros exposure fixed graphs Greenwich Harvard heavenly bodies heliometer Hence illustration images important inches instance instru instrument large number large telescopes largest telescope lens Lick Observatory light lines Mars Max Wolf measure ment meridian method micrometer minor planets mirror Moon motion Mount Hamilton nebula object observations orbit ordinary pair Paris Observatory photometer picture planetary Pole position present prism Professor Pickering recently recognise reflector refractor remarked réseau revolving rotation satellites Saturn screw seen Sir David Gill Sir William Huggins spectra spectroscope spectrum strument Sun's distance taken tele tion transit-circle transits of Venus William Huggins Yerkes Yerkes telescope