t 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;