ASC

Ascending currents, action of, in
producing rain, 138, 288
Ascension, diurnal range of tem-
perature at, 216; annual range
at, 218; rainfall at, 321
Ashes from volcanoes borne by up-
per currents, 243

Asia, Central, annual range of pres-
sure in, 93, 259
Astronomy, contrasted with meteo-
rology, 1

Atlantic Ocean, motion of air over
the, 352; limits of trade winds
in, 246; currents of the, 299;
rainfall of the, 327; the central,
annual range of pressure over, 93
Atmometer, v. Lamont's, 100
Atmometry, Schmid on, 101
Atmosphere, height of, 12; constitu-

tion of, 13; variations in con-
stitution, 15; circulation of, ex-
plained, 240; overflow of, near
equator, 242. See Air.
Attached thermometer in barome-
ters, 70

August, on hygrometry, 108
Aurora, description of, 191; noise

of, 192; the 'corona,' 192; the
dark segment, 192; colour of,
192, 193; at low levels, 193;
height of, 193; geographical dis-
tribution of, 194; in southern
hemisphere, 195; relation of, to
weather, 195; relation of, to
magnetism, 196

Autumn rains, regions of the, 332

BOO

Barograph, Brooke's, 77; Ronald's,
77; Redier's, 77; King's, 78
Barometer, invention of the, 63;
Torricelli, 63; Pascal, 65; best
material for scale, 66; graduation
of the, 67; vernier, 67; mode of
setting, 68; attached thermome-
ter, 70; management of, 71
verification of, 74; defects of,
82; air in tube of, 82; boiling
of, 82; pipette, 83; reasons for
its rise or fall, 248

- corrections; capacity, 73, 84;
capillarity, 84; index error, 84;
temperature (reduction to 32°),
85, 391; altitude (reduction to
sea level), 85, 391; diurnal range
of, 88; Buchan on, 91; Eaton
on, 90; annual range of, 93
Barometers, standard, 72; Fortin's,
72; Kew pattern, 73; marine, 74;
siphon, 75; wheel, 76; aneroid,
79; metallic, 80
Barometrical pressure, on causes
which produce changes in, 248;
regions of reduced, 250; relation
of, to wind, 253, 353; relation of
to isabnormals of temperature, 257
Batavia, rainfall of, 323

Bearings of wind, true and com-

pass, 148

Beaufort's wind scale, 158; veloci-
ties corresponding to, 159
Beckley, automatic rain gauge, 132
Behring's Strait, checks course of
currents, 298, 318

Bidston Observatory, exceptional
pressure of wind at, 156
Binnie, on evaporation at Nagpoor,
99

Black bulb thermometer in vacuo,
53; its use, 55

Blanford, on monsoons, 264; on the
soft place in the monsoon, 268;
on land and sea breezes, 286
Boiling of barometers, 82
Boiling point of water, 21; its use in
hypsometry, 21

Boothia Felix, diurnal range of
pressure in, 89; of temperature,

216

BOR

Bora, the, 292, 383

Bossekop, aurora at, 192
Bourdon's metallic barometer, 80
Bourke, Commander E. G., on cold

currents of Atlantic, 303
Brazil, daily thunderstorms in,
(Caldcleugh), 130, 147, 191; cur-
rent, the, 305

Breezes, land and sea, 285; Blan-
ford on, 286

Brewster, Sir D., on poles of cold,
234

British Isles, the, annual variation

of wind velocity in, 164; distri-
bution of winds in, 276; sea tem-
perature on the coasts of, 319;
weather telegraphy in, 362
Brooke's barograph, 77
Brussels, laws of atmospheric elec-
tricity at, 171

Buchan, A., on diurnal range of
barometer, 91; on predicting
hoar frost, 117; isothermal
charts, 222; isobaric charts, 238
Buitenzorg, rainfall of, 323
Buran, the, 293

Buys Ballot's law, 255, 353

CALCUTTA, diurnal range of

pressure at, 89; annual range
of temperature at, 218
Caldcleugh, thunderstorms in Brazil,
130, 147, 191

Calm centre in cyclones, 373
Campbell's sunshine recorder, 58
Capacity correction of barometers,
73, 84

Cape of Good Hope, observed tem-
perature of soil at, 47; winds
near the, 284

Capillarity correction of barometers,
84

Carbonic acid, amount of, in atmo-
sphere, 15

Cator's anemometer, 151
Celsius (Centigrade) thermometer
scale, 19

'Challenger,' H.M.S., cruise of the,
313

Cherraponjee rain of, 325

Cirrus cloud, 124; its motion, Ley,
125; Hildebrandsson, 125
Cistern of barometer, 72
Clavering, on St. Elmo's fire, 178
Climate, on change of, with height
above sea, 338, 345, 346; insular
and continental, 344; chief con-
ditions which affect, 344, 346
Cloud, composition of, 123; levels
at which they float, 123; classi-
fication of, 124; motion of, 129;
amount of, 129; annual and
diurnal period of, 129; colours
of, 205

Clouston, Dr., on distribution of
winds in the Orkneys, 277
Coffin, winds of globe, 163; on re-
lation of wind to pressure, 255
Cold, greatest obtained, 235; com-
pared with heat, 235

Cold currents under warm water,

303; on west coast of Africa, 304
Cold wall of Gulf stream, the, 300
Coldest period of the day, 47; of
the year, 48

Colding, on course of Gulf stream,

COR

Corona of the aurora explained, 192
Coronæ explained, 202
Corposants, 178

Corrections for deducing mean tem-
perature from various observa-
tions, 38

- of barometers, for capacity, 73,
84; for capillarity, 84; for index
error, 84; for temperature, 85,
391; for altitude, 85, 391; for
gravity, 392

- of wind obs. from ships' logs, 284
Coxwell and Glaisher, balloon
ascent, 12, 66

Croll on ocean currents, 221; on the
Gulf stream, 301
Cumberland Lakes, rainfall of the,
330

Cumulostratus cloud, 127
Cumulus cloud, 127

Currents, atmospheric, ascending
and descending, their action on
precipitation, 138; upper, their
existence proved, 243; equatorial
and polar, 276

ocean, Rennell on, 295; drift,
295; stream, 295; their influence
on sea temperature, 318
Current, the equatorial, 296, 298,
305, 307; the American arctic,
298; the Gulf stream, 221, 297,
299, 301, 302; the Kuro Siwo,
221, 296, 306; Humboldt's, 299,
307, 344; of Southern Ocean,
298, 309; of South Pacific, 307;
the Agulhas, 308; in Polar
Regions, 309

Cyclones defined, 365; indraft of

air in, 366, 369, 374; localities
of, 367 seasonal distribution of,
368; fall of barometer in, 368;
waves caused by, 375; motion of,
370, 372, 379; position of greatest
danger in, 370; segments of, 370;
handling of ships in, 371; calm
centre in, 373

Cyclonic system. See Depression.

DIU

Dalton's law of mixed gases not true
for atmosphere, 112

Dampier, on rain at Gorgonia, 138;
on land and sea breezes, 285
Danckelmann, von, on rainfall of
Indian Ocean, 327
Daniell's hygrometer, 103
Dark segment, of the aurora, 192
Davos, solar radiation at, 56
Day, length of, in various latitudes,

Deep sea temperatures, 310
De La Rue, comparison of lightning
with electric spark, 180; on
colour of aurora, 193

Density, maximum, of fresh water,
312; of sea water (supposed),
313

Depressions explained, 354; air
motion in, 357, 368; contrasted
with anticyclones, 357; passage
of, described, 358; phenomena
on opposite sides of, 359; motion
of, 361, 378, 380; subsidiary or
secondary, 378

Deviation of winds owing to earth's
rotation, 245

Dew, Wells' theory of, 114; ex-
planation of, 118; excessive in
tropical climates, 118; annua'
amount of, 119
Dewpoint, 103, 115

Dines, hygrometer, 104; on annual

amount of dew, 119; on influence
of height on rainfall, 134; on
rainfall in London, 332; on rain-
fall at Cobham, 334

Distribution of land and water on
the globe, 11; its effect on tem-
perature, 219

of plants and animals, 338, 342
Diurnal range of pressure, 88; at
Greenwich, 89; at Calcutta, 89;
at Nertschinsk, 89; in Boothia
Felix, 89; in British Isles, 91

temperature, 37; at Green-
wich, 40; dependent on amount
of sunshine, 214

of cloud, 129

of rainfall, 147

of wind velocity, 163

DIU

Diurnal range of thunderstorms, 190
Doldrums, rain of the, 325
Dorpat, discussion of wind velocity
at, 166

Dove, calculation of dry air pressure,
90, 113; theory of hail forma-
tion, 146; isothermal charts, 222;
relative temperature of two hemi-
spheres, 230; isabnormal charts
of temperature, 232; cause of
Trade wind, 244; change of direc-
tion of winds, 254; cause of Mon-
soons, 265; on West Monsoons
of the Line, 267; on equatorial
and polar currents, 276; weather
rules, 349; law of gyration, 360
influence of,

Drainage,

effects of rainfall, 136
Drift currents, 295

Dry air pressure, 90, 113

on the

Dry and wet bulb thermometers,
107

Dryness of air, its effect on radia-
tion, 57, 62

Dublin, annual range of temperature
at, 45; evaporation at, 102

EARTH, the form of, 6; orbit

of, 7; rotation of, 8; motion
of, in its orbit, 8; effect of
motion on solar action, 45, 211;
condition of its surface in relation
to solar radiation, 46; in relation
to terrestrial radiation, 60
Eaton (H. S.), on diurnal range of
the barometer, 90
Ecliptic, inclination of the, 8
Electricity, atmospheric, 167; laws

of, at Brussels, 171; changes of,
during thunderstorms, 172
Electric potential, defined, 170
Electrometer, Thomson's, 169
Electroscopes, 168
Equation of continuity, 297
Equator, diurnal range of tempera-
ture at, 216; the thermal, 224
Equatorial current, atmospheric, 276
ocean, 299, 305, 307
Frman, Adolf, on relation of wind
to pressure. 254

Ferrel, on relation of wind to pres-
sure, 255

Firescreens, glass, action of, 53
Fitzgerald, M., on globular light-
ning, 176

FitzRoy, Admiral, on weather of
globe, 363

Five day means for temperature, 43
Floats, fishing, Norwegian, found
in Labrador, 309

Floods, connected with drainage,
136

Fog, composition of, 119; forma-

tion of, 120; Aitken's theory,
120; density of, in Newfound-
land, 120; in Spitzbergen, 122;
sea, 122; entry of, in journals,

129

Fogbows (fog-eaters), 201

Föhn, the explanation of, 289; in
Greenland, 289

Forecasting, its difficulty, 361
Forests, influence of, on water sup-
ply, 136

Forked lightning, 173
Forties, the roaring, 264
Fortin's barometer, 72
Fox,' drift of the, 309
Fraction of saturation, 110
France, evaporation in, 102
Franklin, invention of lightning

FRE

conductors, 167, 183; proof of
nature of lightning, 167

Freezing of sale water, 311; of
fresh lakes, 312

Frequency of winds from various
points, 276-281

GA

ALES, straight-line, so-called,
explained, 377

Galileo, observation of height of
water in a pump, 63

Gas explosion, extraordinary effects
of a, 156

Gases and vapours, differences be-
tween, 95

Gay-Lussac's pipette, 83
Gilbert, Dr., evaporation from vari-
ous crops, 99

Glaisher, Jas., balloon ascent, 12,
66; on terrestrial radiation, 61;
hygrometric tables, 109; factors,
109; rain gauge, 131; on wind
pressure, 158; winds at Green-
wich, 277

Glasgow, excessive wind pressure
at, 158

Glazed frost, 115; its effects in
France (1879), 116
Globular lightning, 175
Glories, 203

Godefroy, on glazed frost, 116
Gradients, barometrical, explained,
353

Graduation of thermometers, 21; of
barometers, 67

Grass, its influence on terrestrial
radiation, 60

Gravity, correction of barometer
readings for, 392

Greaves, C., on evaporation, 102
Greenland, Föhn in, 289; climate,342
Greenwich, diurnal range of tem-
perature at, 40, 216; chronoiso-
thermal diagram for, 48; diurnal
range of pressure at, 89; annual
range of temperature at, 218; ex-
cessive wind-pressure at, 158;
distribution of winds at, 276
Guinea current, the, 303
Gulf-stream, the, 221, 297, 318; its

HEA

course, 299; its influence, Croll
301; Haughton, 301; on the
coasts of Europe, 302; in Polar
Regions, 309
Gulf-weed, the, 303
Gyration, the law of, 360

[ADLEY, theory of Trade winds,

HAD 244

Hail, soft, 143; true, 143; insur-
ance, 146; connected with thun-
derstorms, 190

Hailstones, 143; Abich op, 143;
Delcros on, 144; formation of, 145;
Volta's theory, 145; Dove's theory,
146

Hair hygrometer, 105

Hall, Basil, ascent of the Peak of
Teneriffe, 112

Hallsberg, whirlwind at, 382
Halos, explanation of, 203; relation
of, to weather, 205
Hammerfest harbour, 221

Hann, on the causes of rain, 138, 139;
on relative temperature of the two
hemispheres, 231; on the effect of
height on temperature, 236; on
prevalent winds and thermal
windroses, 280; on hill and val-
ley winds, 288; on the 'Bora,'
383; on rainless regions on land,
328; on influence of mountains
on rainfall, 328; on zone of maxi-
mum rainfall, 329; on seasonai
rainfall of Europe, 333
Harmattan, the, 293
Haughton, Dr., the sun compared
with the earth as a source of heat,
51; on evaporation in various
latitudes, 101; on effect of rain-
fall on climate, 140; on motion
of currents, 297; on influence of
Gulf-stream, 301; on the Kuro
Siwo, 306

Heat, amount of, received by each
hemisphere, 10; solar, affected by
motions of earth, 45, 211; by
conditions of surface, 46; varia-
tion of, in the daily and annual
period, 47; sources of, 50; great-