What is the cause of this motion, what is the law
of this motion, is at present beyond our power to
find out. Many years ago a German astronomer
made the random suggestion that possibly we were
revolving in an orbit round the Pleiades as a centre.
The suggestion was entirely baseless, but unfortunately
has found its way into many popular works,
and still sometimes is brought forward as if it were
one of the established truths of astronomy. We can
at present only say that this solar motion is a mystery.
There is a greater mystery still. The stars have
their own individual motions, and in the case of a
few these are of the most amazing swiftness. The
earth in its motion round the sun travels nearly
nineteen miles in a second, say one thousand times
faster than the quickest rush of an express train.
The sun's rate of motion is probably not quite so
swift, but Arcturus, a sun far larger than our own,
has a pace some twenty times as swift as the orbital
motion of the earth. This is not a motion that we
can conceive of as being brought about by gravitation,
for if there were some unseen body so vast as
to draw Arcturus with this swiftness, other stars too
would be hurtling across the sky as quickly. Such
'runaway stars' afford a problem to which we have
as yet no key, and, like Job of old, we are speechless
when the question comes to us from heaven, 'Canst
thou guide Arcturus and his sons?'
It will be seen then that, fundamentally, Greenwich
Observatory was founded and has been maintained
for distinctly practical purposes, chiefly for
the improvement of the eminently practical science
of navigation. Other inquiries relating to navigation,
as, for instance, terrestrial magnetism and
meteorology, have been added since. The pursuit
of these objects has of necessity meant that the
Observatory was equipped with powerful and accurate
instruments, and the possession of these again
has led to their use in fields which lay outside
the domain of the purely utilitarian, fields from
which the only harvest that could be reaped was that
of the increase of our knowledge. So we have been
led step by step from the mere desire to help the
mariner to find his way across the trackless ocean, to
the establishment of the secret law which rules the
movements of every body of the universe, till at
length we stand face to face with the mysteries
of vast systems in the making, with the intimate
structure of the stellar universe, with the apparently
aimless, causeless wanderings of vast suns in lightning
flight; with problems that we cannot solve, nor hope
to solve, yet cannot cease from attempting, problems
to which the only answer we can give is the confession
of the magicians of Egypt—'This is the
finger of God.'
Aberration of light,
79
Adams, John C., his discovery of Neptune,
217
Adhara,
183
Airy, George Biddell, seventh Astronomer Royal, his early life,
102;
his work at Cambridge, 105;
comes to Greenwich, 105;
his relations with the Visitors, 106;
his autobiography, 108;
his character, 111;
his labours, 113;
attacks on, 114;
his distinctions, 118;
his resignation, 119;
his death, 120;
anecdote of, 142;
his conduct re Adams, 217;
his water telescope, 304
Alderamin,
183
Almagest,
185
Almanac making,
29
Alpha Aquilæ, telescope for,
303
—— Cygni, telescope for,
303
Altazimuth the,
114;
description and work of, 207, et seq.
Altazimuth Department,
205,
et seq.
American time,
153
Andromeda nebula,
301
Anemometer, use of,
238;
trace of, 242
Angström,
268
Anson, Commodore,
17
Apparent time,
152
Arcturus, motion of,
315
Argelander, star catalogue of,
287
Art of Dialling, the,
28
Assistants, position of the,
98,
100,
117,
137
Astrographic chart,
128
—— Department,
284,
et seq.
—— dome,
128
—— telescope,
289,
et seq.
Astronomers Royal, the,
25
Astrophysical researches,
282
Auroræ,
281
Automatic register,
241
Axis of the earth, precession of,
184
Ball, Time,
162
Barometer, use of the,
192,
233
Battery basement,
161
Beaufort, Captain,
107
Bessel quoted,
266
Betelgeuse,
184
Birkenhead, wreck of the,
180
Bliss, Nathaniel, fourth Astronomer Royal, history of,
82
Bradley, James, third Astronomer Royal, his life,
73;
his ordination, 74;
Vicar of Bridstow, 74;
Savilian Professor of Astronomy, 75;
discovers Aberration of Light, 75, et seq.;
becomes Astronomer Royal, 79;
labours of, 80;
character of, 81
Bradley's transit room,
128
Brinkley, Dr.,
303
British Mariner's Guide, the,
90
Bunsen,
268
Buys Ballot's law,
237
Canadian time,
153
Castor,
74,
306
Catalogues, star,
182,
185,
et seq.,
198,
284
Cepheus,
183
Charles II., warrants of,
39,
40
Christie, W. H. M., eighth Astronomer Royal, work of,
120
Chromosphere of the sun,
268
Chronograph, the,
157
—— room,
126
Chronometer business,
101,
107
Chronometers, Harrison's improvements in,
165,
et seq.;
tests of, 169;
'runs' of, 173;
romance of, 178
Circle Department,
181,
et seq.
Clock, Astrographic driving,
290;
driving 28-inch telescope, 312
Clocks, standard,
160
Columbus, aim of voyage of,
18
Comet, appearance of a,
28
—— Wells,
280
Comets, observation of,
224;
spectra of, 280
Commutator, the,
162
Comte, assertion of,
267
Constant of Aberration,
79
Cook, Captain, work of,
170
Copper, use of in Observatory,
245
Corona of the sun,
264
Crabtree, James,
31
Crosthwait, Joseph,
57
Dallmeyer telescope,
252
Declination,
186,
et seq.
Denebola,
184
Distances of planets,
223;
of sun, 224
Double-Star Department,
303,
et seq.
Double Stars,
306
Dublin time,
155
Dunkin, Edwin,
315
Earth, the, movements of,
201
Eclipses of the moon,
216;
of the sun, July 25, 1748...85;
other eclipses of the sun, 263, et seq.
Electric Railway, influence of,
249
Equation of Time, the,
29,
151
Equatorial, Shuckburgh's,
101
——, the great 28-inch,
221
——, the Merz, 12
3/4-inch,
114
——, 28-inch, driving clock of,
309;
use of, 313
——, clock-driven,
74
Eros, discovery of,
223;
photographs of, 298
Errors in observations, noting of,
199,
et seq.
Evaporation,
241
Faculæ of the sun,
257
Flamsteed, John, his report on Saint-Pierre's proposal,
23,
32;
appointed first Astronomer Royal, 23, 34;
his autobiography, 26;
his studies, 29;
his almanac, 29;
sent to London, 30;
enters Jesus College, Cambridge, 31;
completes his observatory, 31;
acquaintance with Newton, 31;
takes his degree, 32;
his work, 34;
warrant for his salary, 39;
position of, 42;
his ordination, 45;
his pupils, 45;
his trouble with Newton, 46, et seq.;
his catalogue, 53;
his letter to Sharp, 54;
his death, 56;
his labours, 57
Flamsteed House,
126
Fraunhofer mounting,
310
French time,
155
Galileo, his discovery of Jupiter's satellites,
19
Gamma Draconis,
75,
304
—— Virginis,
306
Gascoigne, William,
31
Gemma Frisius, plan of,
22
George of Denmark, Prince,
50
German mounting,
276,
310
Gould, Dr.,
287
Graham,
166
Gravitation, the bond of the universe,
313
Great comet of 1882, the,
280,
288
Greatrackes, Valentine,
29
Green, Charles,
91
Greenwich time,
153;
distribution of, 163
Halley, Edmund, his life,
60;
his early work, 60;
his catalogue of stars, 63;
elected F.R.S., 63;
his work on Kepler's laws, 64;
becomes captain, 65;
Savilian Professor of Geometry, 66;
Astronomer Royal, 66;
observations on saros of the moon, 67;
pressed by Newton, 68;
his death, 68;
his services to science, 68;
his pay, 70;
nominates his successor, 73;
his transit instrument, 73
Halley's comet,
225
Harrison, James, timekeepers of,
86,
91,
93,
165
Heineken, Rev. N. S.,
59
Heineken quadrant,
59
Heliographic Department,
251,
et seq.
Herschel, Caroline,
57
Hipparchus, catalogue of,
185
Hodgson, Mr.,
50
Hooke, Robert,
75,
206
Horrox, Jeremiah,
31
Huggins, Sir W., his use of spectroscope,
268
Inscription, an,
126
International Photographic Survey,
296
Ireis,
224
Iron quadrant,
73
Isobars,
237
Jupiter, satellites of,
19,
296;
atmosphere of, 279
Keill, John,
74
Kendall, Larcum,
166
Kepler, laws of,
64
Kew, photo-heliograph, the,
252
Kinnebrook, David,
176
Kirchhoff's use of spectroscope,
267
Latitude, finding the,
18
Ledgers, chronometer, romance of,
176
Leverrier, his discovery of Neptune,
217
Libraries,
132
Linacre, G.,
28
Lindsay, Thomas, quoted,
204
Litchford, W.,
28
Local apparent time,
22
Longitude, finding the,
18;
at sea, problem of, 86;
determination of, 173
Longitude nought,
148
Lower computing room,
128
Lunars, method of,
86
Magnetic Department, work of,
133;
description of, 228, et seq.
Magnetic inclination and declination,
246
—— needles, movements of,
247,
262
—— observatory,
132
—— pavilion,
245
—— storms,
248,
262
Mars, distance of,
223;
atmosphere of, 279;
satellites of, 296
Maskelyne, Nevil, fifth Astronomer Royal,
85;
practical work of, 86;
Astronomer Royal, 91;
his work, 92;
his publications, 92;
his observations and work, 92, et seq.;
his death, 94;
his character, 97;
recommends his successor, 97;
his mural circle, 101
Mean solar clock,
160
Mean time,
152
Meldrum, Dr., on sun spots,
263
Meridian, the,
149
Merz telescope,
279
Meteorological Department, work of,
133;
description of, 228, et seq.
Micrometers, use of,
309
Microscopes, use of,
188
Milky Way,
288
Miller, Professor,
268
Milne, Professor, on earth movements,
201
Minor planets,
222
Molyneux, Samuel,
75
Moon, observation of the,
212,
et seq.;
eclipses of, 266
Moore, Sir Jonas,
30;
death of, 42
Morin,
33
Mounting telescopes, modes of,
310
Mudge, Thomas,
94
Mural arc, 7-feet,
46
Mural circles,
101,
196
Names of stars, origin of,
183
Nares, Sir George,
170
Nautical Almanac, the,
22,
23,
92
Navigation, state of primitive,
17
Neptune, discovery of,
217;
atmosphere of, 280;
satellite of, 298
New altazimuth, the,
132,
210
New Observatory, the,
136,
275
New stars,
268
Newcomb, Professor, on growth of Observatory,
124;
on Greenwich observations, 207
Newton, Sir I., his absent-mindedness,
31;
his trouble with Flamsteed, 46, et seq.;
on Kepler's laws, 65;
his Principia, 65;
his pressure on Halley, 68;
his discovery of gravitation, 206
North terrace, the,
126
Northumberland equatorial,
218
Nutation of the earth,
80
Observation, modes of,
156,
176,
188;
by reflection, 196;
of comets, 224
Observatory, Greenwich, work of,
13;
foundation of, 23;
warrant for building, 40;
position of, 41;
foundation stone laid, 42;
condition of, 79;
enlargement of, 112;
recent extensions of, 120;
description of, 124, et seq.;
staff of, 137;
work of, 139, et seq.;
visitors to, 175;
new altazimuth building, 211;
magnet house, 228;
magnetic pavilion, 245;
new Observatory, 275;
future of, 283;
reflex zenith room, 304;
objects of, 316
Occultations by the moon,
212,
et seq.
Octagon room,
125,
238,
242
Oldenburg, Mr.,
30
Orion nebula,
268,
301
Parallax of stars,
303
Paramour, the,
65
Paris, conference at,
288
——, noon at,
151
Philip III., offer of,
19
Photographic registration,
244,
247,
252,
255;
refractors, 288
Photographs, star,
290
Photo-heliographs,
252,
et seq.,
279
Piazzi, discovery of,
222
Pleiades, the,
301
Polar plumes of the corona,
264
Polaris,
188
Pole-star, variation of,
184
Pond, John, sixth Astronomer Royal, his life,
97;
his reign, 98;
his salary, 98;
his assistants, 98;
his observations, 99;
censured by Visitors, 99;
his observations of stars, 303
Pound, James,
73
Precession of earth's axis,
184
Principia, publication of,
65
Proctor, R. A., attack of,
116
Ptolemy, Claudius, catalogue of,
185
Publication, the problem of,
48,
92
Quadrant, Heineken,
59
——, the iron,
73
Railway time,
152
Rain gauge,
238
Record rooms,
132
Reflection, observation by,
196
Reflex zenith room,
304
—— —— tube,
131
Refraction, effects of,
194
Right ascension,
186,
et seq.
Roberts, Dr. Isaac,
301
Römer, discovery of,
78
Rosse, Lord,
268
Royal Society and Flamsteed,
46,
et seq.
Saint-Pierre, Le Sieur de, proposal of,
23,
32
Sappho,
224
Saros of the moon,
67
Satellites, discovery of,
296
Saturn, atmosphere of,
279;
satellites of, 296
Schaeberle's comet,
280
Schedar,
184
Schiehallion, attraction of,
94
Schönfeld,
287
Scotchmen, anecdote of,
146
Sharp, Abraham,
46
Sheepshanks, Rev. James, on Airy,
107
Shuckburgh equatorial,
309
Sidereal clock,
160
Sirius,
287
Sloane, Dr.,
50
'Smith, Mr.,' his chronometer,
179
Solar photographs,
257
—— storms,
261,
282
Sound waves,
271
South, Sir James,
105,
114
South-east equatorial, the,
132,
221
Spectroscope, use of,
267
Spectroscopic Department,
266,
et seq.
Spots, sun,
251,
et seq.,
281
Staff of Observatory,
137;
work of, 139, et seq.
Standard time,
21
Stars, observations of,
156,
176,
188;
origin of names of, 183;
movements of, 187;
catalogues of, 198, 284, et seq.;
composition of, 268, et seq.;
colour of, 271;
classes of, 287;
census of, 287;
photographs of, 288, et seq.;
motions of, 303, 315
Story, Mr. A. M.,
97
Sun, distance of the,
74,
224;
spots on, 251, et seq., 281;
eclipses of, 263, et seq.;
chromosphere of, 268;
motions of, 315
Sunshine recorder,
238
Swiss time,
155
Tebb, Mr. W.,
58
Tebbutt's comet,
280
Telescope, the great transit,
156
——, 28-inch,
275
——, astrographic,
289
——, Shuckburgh,
309
——, Thompson,
256,
279,
296
Thalèn,
268
Thermometer, use of,
192,
234
Thome, Dr.,
287
Thompson photo-heliograph,
256,
279,
296
Time ball,
162
—— Department, the,
146,
et seq.
—— desk,
161
——, foreign,
153
—— signals,
162
—— standard,
21
Transit, Halley's,
73
Transit circle, the,
114;
mode of observation with, 188, et seq.
Transit circle, Troughton's,
98
—— Department,
181,
et seq.
—— observations, number of,
140
—— pavilion,
126,
175
—— room,
128,
147
Troughton's transit circle,
98
Uranus, discovery of,
217;
atmosphere of, 279;
satellites of, 296
Vanes, use of,
238
Venus, distance of,
223
Victoria,
224
Visitors, the Board of,
53;
censures Pond, 99;
work of, 106;
constitution of, 144
Visitors to Observatory,
175
Warrant for Flamsteed's salary,
39
Water telescope,
304
Weather predictions,
229,
et seq.
Winds, study of,
237
Witt, Herr, discovery of,
223
Working Catalogue, the,
142
Zenith sector,
82,
305
—— tube,
75,
305
Zeta Ursæ Majoris,
306
Zubeneschamal,
184