studies of Mars, 275

Belopolsky, coronal photographs, 185;
theory of corona, 191;
rotation of Venus, 252;
of Jupiter, 297;
spectroscopic determinations of Saturn's rings, 300;
spectrum of Gamma Cassiopeiae, 378;
system of Castor, 389, 391;
detection of variable stars as spectroscopic binaries, 391

Berberich, mass of asteroids, 287;
orbit of Holmes's comet, 337

Berkowski, daguerrotype of eclipsed sun, 166

Bessel, biographical sketch, 28-30;
reduction of Bradley's observations, 32;
parallax of 61 Cygni, 36;
disturbed motion of Sirius and Procyon, 41;
trans-Uranian planet, 79;
Halley's comet, 102;
theory of instrumental errors, 122;
personal equation, 123;
rotation of Mercury, 246;
lunar atmosphere, 263;
cometary emanations, 325, 345;
multiple tails, 347;
comet of 1807, 352

Betelgeux, remoteness, 37, 417;
spectrum, 373, 381, 383, 384;
radial movement, 387

Bianchini, rotation of Venus, 250

Biela, discovery of a comet, 95

Bigelow, magnetic and solar disturbances, 161;
theory of corona, 191

Bigourdan, eclipse of 1893, 187;
velocity of comet of 1882, 364

Bird's quadrants, 4, 112, 121

Birmingham, colours of stars, 375 _note_;
discovery of T Coronae, 393

Birt, rotation of a sun-spot, 144;
Selenographical Society, 266

Bischoffsheim, Coude telescope, 436

Black Ligament, 235

Bode, popular writings, 5;
solar constitution, 57;
missing planet, 72, 73

Bode's Law, 71, 83, 286

Boeddicker, heat-phases during lunar eclipses, 269, 270;
drawings of Jupiter, 296;
of the Milky Way, 424

Boehm, solar observations, 146, 148

Boguslawski, centre of sidereal revolutions, 41;
observation of Halley's comet, 102

Bolometer, principle of construction, 222

Bond, G. P., his father's successor, 86;
light of Jupiter, 289;
Saturn's rings, 298;
Donati's comet, 324, 325;
Andromeda nebula, 409;
double-star photography, 409

Bond, W. C., observation of Neptune's satellite, 84;
discovery of Hyperion, 85;
of Saturn's dusky ring, 86;
resolution of nebulae, 119;
celestial photography, 153, 409;
satellite-transit on Jupiter, 291

Borda, repeating circle, 121

Boss, solar translation, 40;
observations on comets, 352, 356

Bossert, proper motions of stars, 415

Bouguer, sola