Galaxy, def. 107; also F 277, 420
Galileo, 214

Galvanism, 198-199
Gambart, M., Comet of, P 272,
and 4 of S 273

Gay Lussac, M., note to def. 27
Gemini, a of, a Double Star, L
279

Geocentric, def. 99

Georgium Sidus. See Uranus
Glass, Refracting power of, P
185

Globe or Sphere, B 8
Globe, Terrestrial, def. 8
—, Celestial, def. 11

Gnomon, of the Ancients, foot-
note, 395

Gnomon of a Sun-dial, 2 p. 380
Golden Number, 336-337
Gorgon Head, note, 408

Hecate, a name of the Moon, 299
Hercules, note, 409

Height of Atmosphere, 2 of M
170

of Tides, F and G 346
Heliacal, 357

Heliocentric, def. 100

Helix, (illustration,) X 203,
note

Hemisphere, def. 32

Hercules, note, 409

Herschel, Sir W., S 239, H and
K 278-279

Herschel, Sir J. F. W. (in nu-

merous quotations)

Herschel, Planet of. See Uranus.
Hesiod, W 357, Ex. 1, 367
Heteroscii, def. 74

Hesperus, a name of the Planet
Venus, 266
Hevelius, 409, note

429

Hicetas, 395

Hipparchus, 397

Home, 421

Hooke, Dr., 215

Horizon, Dip of the, D 10; L

21

,Plane of the, C 10
,Rational, B 10, and def. 28

-, Sensible, B 10, and def. 27
-, Wooden, def. 29

Horizontal Refraction, note, 413;
also Ex. 6 and 7, p. 135
Horizontal Parallax, N 18 (illus-
tration)

Horoscope, R 390, also quota-
tion on p. 366
Horary Circle, def. 25
Hour-circles, def. 26

Human Body, Atmospheric Pres-
sure on, 1 and 2 of N 171
Hurricanes, foot-note, 293
Huygens V, 229

-, Theory of Light of, S
186; also foot-note, 191
Hyperbola, R 22

I.

Icebergs, note to Ex. 2, p. 134
Illustrations, Ecliptic, 104-108
Immersion, note, def. 58
Impetus. See Inertia, illustra-
tions of.

Imponderable Matter, 166
Indians, Astronomy of the, X
394

Inequalities, Lunar, 303-308;
also N 353

Inertia, D 207

Illustrations of, 212
Influence of Varieties of the

Earth's surface, 294-296
Insignificant Quantities, F and
G 4, H 5, B 10
Instinct, B 190

Inverse square of distance, C 13,
and illustration, 14
Invisible Rays, 188-189
Iron, its Magnetic properties.
See Magnetism.

Light, Discovery of Velocity of,
R 254

—, Aberration of, 265
"Limb" of the Sun or Moon,
def. 57

Line, straight, C 1
Liquids, H 168

Longitude of a place, def. 23,
also p. 59

, of a heavenly body, 153
, length of a Degree of,

M 226
Lubbock, Mr., extract from his
Tide Tables, 349
Lucifer, a name of the planet
Venus, 266

Luminary, Rays of a, B 13
Lunar Eclipses, duration, &c., of,
X 327

Lunar Observations, 64-65
Lunar Orbit, Excentricity of, N
299, B 306

Lyra, a of, a Double Star, L 279