Alexander, spiral nebulæ, [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 Aurigæ, [396];
of Nova Persei, [400]
Andrews, conditions of liquefaction, [151]
Ångström, C. J., Optical Researches, [138];
spark spectrum, [139]
nature of photosphere, [152]
solar spectroscopy, [210] [212]
hydrogen in sun, [211]
temperature of stars, [375]
Ångström, 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 auroræ, [130]
nature of photosphere, [151]
meteor-systems, [329]
Arai, photographs of corona of 1887 [185]