Alexander, structure of the Milky Way, 214

Amœba, versatile organization, 274-5

Anaximander, generalized matter, 5

Anaximenes, air as the 'Urstoff,' 4, 151

Aristotle, conception of nature, 8;
solid spheres, 13

Asteroids, orbital relations, 236


Babinet, objection to Laplace's cosmogony, 44

Bacon, elemental triad, 151

Ball, Sir Robert, mechanics of a condensing nebula, 79, 209-10

Barnard, discoveries of nebulæ, 212;
observations of the Gegenschein, 259

Becquerel, detection of radio-activity, 157, 162

Bessel, astronomy of the invisible, 141

Bode's law of planetary distances, 26

Brorsen, the zodiacal counterglow, 259

Bruno, a platonic pantheist, 9

Buffon, cometary impacts, 61;
fossil foraminifera, 275


Campbell, system of ζ Geminorum, 113;
number of spectroscopic binaries, 143;
density of nebulium, 153

Chladni, meteoric cosmogony, 118

Comets, position in Cartesian system, 12-13;
in that of Laplace, 136;
origin, 73-4, 252-4;
meteoric relations, 122-4, 133;
solar dependants, 133, 140, 236, 251;
nebular affinities, 137, 254-5;
insignificant mass, 242

Cosmogony, primitive, 1-3, 14;
philosophical, 3-7;
scientific, 7, 15;
of Descartes, 11-13, 60;
Kant's, 21-28, 61-2, 252, 254;
Laplace's, 29-33, 38-53, 57-61, 138, 235;
Herschel's, 35-7, 136, 199-201;
Faye's, 68-76, 81, 129;
Lockyer's, 125-134;
sidereal, 105-7, 145-7, 217-230

Crookes, Sir William, protyle, 5, 149;
radiant matter, 154, 156-7;
future of the world, 163

Curie, Madame, discovery of radium, 162


Dalton, combining equivalents, 152

Dark stars, 141, 226-7

Darwin, condensation of nebulous rings, 42, 51;
history of earth-moon system, 87-92, 94, 97, 142;
equilibrium of rotating globes, 102, 104-5, 112, 143;
fluid pressure on meteor-swarms, 129, 131;
spiral nebulæ, 205

Delambre, on cosmic speculations, 14, 15

Democritus, mechanical theory of the world, 5, 22

Descartes, theory of vortices, 11-13

Dissipation of energy, 229

Double stars, genesis and development, 98-9, 106-7, 142-5, 226-7;
occulting, 108-113;
variable, 113-115, 143;
'dumb-bell' type, 115, 116, 143;
frequency of occurrence, 144, 234


Earth, effective rigidity, 86;
critical situation, 87;
antique disruption, 89, 91;
tidal effects upon, 90, 244;
meteoric intakes, 119-120, 133;
internal heat, 266

Easton, the galactic spiral, 214

Eclipses, stellar, 107-8;
questionable occurrence, 109-113;
criterion of reality, 114

Electricity, discharge through vacua, 154;
relations with disintegrated matter, 155, 159-160, 163;
gravity explained by, 177-8, 179;
dual properties, 180-181;
fundamental in nature, 182;
ethereal transmission, 185

Electrons, copious production, 174;
strain-centres, 189-190, 195;
ultimates of matter, 231

Elements, ancient and mediæval ideas regarding, 5, 151;
genesis, 152, 230-231

Empedocles, four elements, 5, 151

Ether, in Cartesian philosophy, 12;
evasive character, 159, 183, 197-8;
relation to gravity, 175, 185;
properties, 184, 191, 193-4

Evolution, of solar system, 22, 241, 250;
of stars, 35-6, 217-225;
of stellar systems, 98-9, 106-7, 142-5, 226-7;
of nebulæ, 145-6, 200-211;
of the chemical elements, 151, 230-231


Faye, objections to Laplace's cosmogony, 25;
modified scheme, 68-73, 81, 129;
duration of the sun, 76

Fleming, nature of electrons, 195

Frost and Adams, spectroscopic binaries, 143, 221


Galileo, first law of motion, 12

Goldstein, cathode-rays, 155

Gravitation, mode of action, 168, 185;
velocity of transmission, 169, 175, 177;
explanatory hypotheses, 170-179


Hale, relationships of carbon stars, 225

Halley, nature of nebulæ, 36

Hansky, status of zodiacal light, 261

Harvey, life from life, 268

Helium, present in the sun, 55;
origin by atomic decay, 158, 230;
absorption in stars, 220, 222-3;
a constituent of nebulæ, 230

Helmholtz, maintenance of solar heat, 31, 34, 35, 74-5

Helmont, spontaneous generation, 268

Heracleitus, elemental evolution, 151

Herodotus, omnipotence of time, 269

Herschel, Sir John, nature of atoms, 156;
Saturn's satellites, 240

Herschel, Sir William, Uranian system, 29;
sidereal evolution,
35-6, 37, 136;
observations of nebulæ, 199;
history of their growth, 200-201

Huggins, Sir William, discovery of gaseous nebulæ, 54, 153

Huggins, Sir William and Lady, stellar development, 226

Huxley, origin of life, 269, 271, 272

Hydrogen, molecular velocity, 55;
the unit-atom, 152;
tenuity, 153;
absorption in stars, 221-2


Island-universes, 54


Jeans, figures of equilibrium, 104-5;
nature of radio-activity, 196

Jupiter's system, 240-1


Kant, cosmological speculations, 20-28, 60-62, 252, 254;
tidal effects, 27, 84-5;
Saturn's rings, 49;
status of comets, 73

Kelvin, Lord, Lesage's theory of gravitation, 174;
vortex-atoms, 187;
dissipation of energy, 229;
origin of life, 268, 280

Kepler, physical astronomy, 10

Kirkwood, objection to nebular hypothesis, 50, 51;
effects of solar tidal friction, 67


Lambert, sidereal construction, 17-18

Langley, mass of meteoric infalls, 119

Laplace, hypothesis of planetary origin, 25, 29-31, 33, 36-42, 52-3, 58-9, 60-62, 235;
Saturn's ring-system, 49;
Mécanique Céleste, 57;
status of comets, 73, 136

Larmor, scheme of molecular physics, 188;
definition of ether, 189, 193

Lenard, cathode-rays, 157

Lesage, rationale of gravity, 172-3, 175

Lewis, masses of double stars, 226

Ligondès, scheme of planetary growth, 77-8, 81, 252;
comets as survivals, 253, 256

Lockyer, Sir Norman, meteoritic hypothesis, 125-7;
enhanced lines, 223

Lorentz, electrical hypothesis of gravity, 177-8, 185


Magellanic clouds, spiral conformation, 213

Marchand, plane of the zodiacal light, 263

Mars, rotation of, 47-8

Maxwell, origin of matter, 161;
corpuscular theory of gravitation, 173

Mayer, J. R., effects of tidal friction, 87

Mercury, action upon of solar tides, 88, 96;
eccentric orbit, 242

Meteoritic formation of planets, 28-9, 119-122, 125, 128, 131-3;
of comets, 122-4;
of nebulæ, 126-7, 134

Meteors, abundance, 119, 133;
mineralogy, 121-2, 134;
hyperbolic orbits, 133;
attendance on the sun, 236

Meteor-swarms, progressive dispersal, 72, 124;
constitution, 122-4, 128-131;
primitive existence, 134

Milky Way, theories regarding, 16-17, 215;
undeveloped condition, 201, 207;
relation to sun's movement, 247

Mohl, protoplasm, 270

Moment of momentum, 23, 40, 44, 45, 65, 209

Moon, origin, 87-92, 97, 139, 145;
retreat from the earth, 244

Moulton, nebular cosmogony, 44, 51, 82

Myers, systems of β Lyræ and U Pegasi, 109-110


Nebulæ, gaseous composition, 37, 153, 201, 205;
illusory resolution, 53;
spiral structure, 79-80, 106, 146, 190, 204-208, 211-214;
classification, 199;
development, 200-202, 205, 207-211;
relation to stars, 202-3, 205;
helium ingredient, 230, 255

Nebular hypothesis, propounded by Kant, 22-8;
by Laplace, 29-31, 38, 52-3, 61;
difficulties, 39-52, 54-6;
amendments, 60-82

Nebulium, a constituent of nebulæ, 54, 153, 201

Neptune, retrograde system of, 43, 52, 237

Newcomb, transverse observation of the zodiacal light, 260

Newton, transmission of gravity, 184, 185

Nova Persei, nebulous appurtenance, 206


Perrine, new Jovian satellites, 240

Pezénas, notice of the counterglow, 259

Phobos, anomalous revolution, 47-8, 237

Phœbe, retrograde motion, 96, 237-8

Pickering, E. C., binary nature of V Puppis, 112;
structural relations of the Looped Nebula, 213

Pickering, W. H., origin of Phœbe, 97, 238;
photograph of a great nebula, 212;
satellite discoveries, 237, 240

Plato, conception of a world-soul, 8

Poincaré, rotational equilibrium, 101, 105, 110, 143;
destiny of the solar system, 243-4

Prestwich, Laurentian graphite, 279

Proctor, structure of the Milky Way, 214

Protoplasm, its properties, 270-273

Protyle, supposed discovery, 149, 154-7;
function and qualities, 152;
cosmic relations, 164-5

Prout, unity of matter, 152


Radio-activity, possible effects, 33-4, 229;
discovery, 157;
nature and cause, 158-9, 162-3, 196

Red stars, affinities, 224-6

Redi, transmission of life, 268

Reynolds, explanation of gravity, 170;
molecular physics, 188, 192-3

Richter, germ-laden aerolites, 280

Roberts, A. W., systems of R² Centauri and of V Puppis, 111, 113

Roberts, Isaac, spiral arrangements of stars, 214

Roche, planet-making expedients, 48;
reconstruction of Laplace's hypothesis, 62-67

Roche's limit, 63, 115-6

Röntgen rays, discovery, 157;
ethereal nature, 158, 176;
electronic effects, 163;
suggested connection with gravity, 176

Rothmann, early notice of the zodiacal light, 256

Russell, photographs of Magellanic Clouds, 213

Rutherford, atomic disintegration, 162


Satellites, periods of revolution, 46;
anomalies of movement, 47-8, 52, 96, 236-9;
effects on of tidal friction, 93-4, 96, 97, 238;
origin by fission, 105;
'asteroidal,' 239-40

Saturnian system, an example to cosmogonists, 41, 71;
anomalies, 49, 52, 96, 237-240

Schaeberle, photographs of nebulous spirals, 204, 212

Secchi, star-classification, 219

See, tidal friction in stellar systems, 98, 142

Shelley's Demiorgon, 9

Solar system, origin, 22, 39-42, 69-82, 241;
anomalies, 29, 43-52, 236-241;
mechanism, 30, 234-5;
stability, 235, 242;
springs of decadence, 243-5;
translation, 245-8

Spectroscopic binaries, 98, 112-114, 142-4, 221

Spencer, status of nebulæ, 54;
spontaneous generation, 270

Spinoza, pantheistic views, 9

Stars, relations to nebulæ, 35-6, 202-3;
distribution, 147;
relative ages, 217-221, 225;
spectra, 221-5

Stokes, Sir George, nature of life, 276

Stoney, criticism of gravitational hypothesis, 179

Sun, mode of development, 25, 31;
maintenance of heat, 31-5;
helium-constituent, 55-6;
stellar relationships, 224-5;
actual standing, 232-3;
motion in space, 245-8

Swedenborg, cosmic evolution, 4, 6, 15


Thales, ideas of cosmic evolution, 4, 14, 151

Thomson, J. J., mass of corpuscles, 158;
gravitational effects, 173;
Röntgen rays and gravity, 176;
ether and matter, 190

Tidal friction, effects in earth-moon system, 28, 87-92, 94, 97, 244;
in other sub-systems, 48, 50, 93-7, 238-9;
on binary stars, 98-9, 108, 142;
modifying power, 46-7, 67-8, 83-7

Tisserand, transmission-rate of gravity, 175


Uranian system, retrograde motion, 43, 52, 70, 237


Variable stars, 108-115

Venus, mode of rotation, 96

Vogel, stellar development, 219, 225


Whewell, status of nebulæ, 54

Whittaker, undulatory theory of gravity, 178-9

Wilson, radium in the sun, 34

Wolf, C., motion of Phobos, 48;
solar tidal friction, 67;
criticism of Faye's cosmogony, 73

Wolf, Max, photographs of the zodiacal light, 263

World Soul, function in cosmogony, 8-9

Wright, theory of the Milky Way, 16-17, 18, 20


Zodiacal light, origin, 256-7, 261, 264;
triple aspect, 257-60;
transversal dimensions, 260;
constitution, 262;
plane of extension, 262-3