Chapter XVII: Science in the Twentieth Century (4)

Darwinian Theory, x, 135, 136, xv, 15, 24-5, 56, xvi, 149-51, 152;
Bagehot on changes wrought by, xvi, 198;
Greek anticipation of, 79;
horror first caused by, xv, 53;
naturalism and, xvi, 111;
philosophical effects of, 195

Dassies, South African, xii, 304

Dasyures, xii, 278

Date Palm Tree, xv, 125

David's Deer, xii, 316

Davos, health resort, i, 210, 325

Davy, Edmund, xvi, 190

Davy, Sir Humphry, electrical work, vi, 16, 19, xvi, 122, 189;
heat studies, iv, 43, xvi, 131;
laughing gas discovery, x, 123-4, 125

Day, divisions of, v, 57, xvi, 57;
mean solar, iv, 15-16;
periods of high and low temperatures, i, 76, xiv, 347-8;
periods of highest energy, xi, 277

Day and Night Breezes, i, 131

Dayflies, xii, 104

Dead Reckoning, v, 65-6

Dead Sea, formation of basin, iii, 151, xiv, 118, 120-1;
level and level changes, iii, 151-2, xiv, 121, 205, 362;
salinity, iii, 152, viii, 139, xiv, 207

Deaf and Dumb, sign language of, xv, 148, 150

Deafness, ix, 103-4;
from brain disease, 146

Death, correlative of life, xii, 13;
"irritability" theory of, x, 86, 87;
James on phenomena of approaching, 242;
physiological meaning, ix, 17;
primitive conceptions of, xv, 327-9, 331-8;
vital knot in relation to, ix, 257

Death Adders, xii, 229

Debtors, treatment of, in African tribes, xv, 370

De Candolle, plant classification, xvi, 165-6;
vegetable table, xiii, 221

Decay, air and, xiii, 312-18;
carbon dioxide from, viii, 49, 61;
humus produced by, 340;
nitrogen from, 73, 346;
phosphorescence from, i, 346, 349, xii, 20

Deccan of India, lava fields, iii, 105, 228, xiv, 103

Deciduous Trees, xiii, 175, 269, 271-2;
of temperate forests, xiv, 370, 371, 372, 373, 374

Decimal System, xv, 181

Declination, of compass needle, iv, 247

Declination of Stars, ii, 299

Decomposition, (chemical), viii, 12, 101;
contrasted with dissociation, 121;
double, 104-5;
of salts, 117

Decrement, of oscillating currents, vii, 286, 287-8

Deeps, ocean, iii, 52, xiv, 9, 23, 286;
volcanoes and, 316

Deep Sea, animal life in, xii, 21-4;
animals, luminosity of, 139;
conditions of life in, 21-2;
darkness of, 22, xiv, 298;
density of, xii, 21;
deposits, iii, 54-5, xiv, 285, 286;
fish of, xi, 53, xii, 20, 23-4, 136, 138-9, 163, xvi, 146;
ground sharks of, xii, 143, 147;
movement of water in, xiv, 284, 298-9;
never over present continents, iii, 55;
ooze, xii, 18, 19;
plants of, 16-17;
seaweeds not found in, xiii, 72;
soundings of, xiv, 284;
temperature, 297, 298, 299;
topographical features, 284, 286-7, 288-90;
unknown to us, v, 202

Deer, xii, 317-20;
evolution of hoofs, iii, 300;
fear in, xi, 136;
heart in, x, 332

Deer Family, xii, 315-20

Deer-hunting, in India, xv, 223

Defectives, human, increase in, xv, 27

De Forest, audion detector, xvi, 191

Degrees, electrical, vi, 204

De Haen, x, 77

Dejection, emotion of, xi, 146;
posture and, 337, 338-40
(see also Despondency)

DeLaval Steam Turbine, v, 148-50, 382

Delaware Indians, prayer song of, xv, 346-7

Delaware River, estuary of, xiv, 40;
geological history, 40, 60, 168-9, 171;
heterogeneous course, 155;
rapids of, 159;
shad season in, xii, 155;
superimposed stream, iii, 233;
transverse characters, xiv, 99, 154, 167;
valley and gap, 50-1, 52, 169

Delaware Water Gap, iii, 233, xiv, 50-1, 167, 169;
rock weathering at, 76

Delco Automobile System, vii, 137

Delco Power Sets, vii, 232

De Lesseps, Ferdinand, Saharan proposal, xiv, 205

Deliberation, after contact and distance sensations, ix, 95, 121, 140;
nervous delays in, 140, 141, xi, 20, 21;
value of, 139

Delirium, Brown on, x, 89;
hot baths in, 311

Delta Connections (electric), vi, 210-11, 318, 325

Delphi, Oracle of, xv, 351-2

Deltas, iii, 32, xiv, 53;
alluvial soil of, 70;
coasts formed by, 53, 263;
in lakes, 202, 210-11;
lakes formed by, 203;
rivers joined by, 185

Delusions, x, 358-9

Demagnetization, vi, 37-8, 117, vii, 366;
by heat, iv, 253;
test, vi, 43

Dementia Precox, x, 237

Democritus, on knowledge, xvi, 87;
on matter, 83;
on origin of earth, ii, 366-7

Demosthenes, timed speeches, v, 62

Denatured Alcohol, viii, 250

Dendrites, xi, 18, 19;
receptors for pain, 117

Denmark, antiquity of man in, xv, 86-7;
föhrden of, xiv, 259;
forests and peat bogs, xv, 86-7

Density, absolute, iv, 110-11;
methods of determining, 111-12;
of liquids, how measured, 113, vi, 147;
of various substances, iv, 113;
specific, 111;
standard of, 149

Densmore, James, v, 312

Dental Arches, xv, 98 (fig.)

Dentistry, hypnosis in, xi, 316;
protection against pain, 121

Denudation (see Erosion)

Denver, boiling temperature in, iv, 170

Deodorants, inhibition in, xi, 81

Department Stores, Christmas lighting, vii, 342;
pneumatic tubes in, iv, 130;
rain and business, i, 265

Deperditometer, i, 319, 371

Depolarization, of electric cells, vi, 137, 139, vii, 366

Depression, of land and sea areas, (see Subsidence)

Depressions, (geological) in land, xiv, 204-5;
in ocean floor, 286

Depressions (meteorological), i, 135, 371 (see Lows)

Depth, perception of, ix, 119-20, xi, 173-85

Derborence, lakes of, xiv, 202

Derived Proteins, viii, 352-3

Derived Units, iv, 46, xvi, 131

Dermographism, xi, 317

Dermoid Cysts, x, 120

Desault, Pierre, x, 91-2

Descartes, influence of, x, 67;
mathematical and scientific work, ii, 15, xvi, 113-14, 118-19;
theory of vortices, ii, 60

Descriptive Astronomy, development of, ii, 15-16, 113-14, 119, 139

Deserts, density of air over, i, 171;
dust whirls, 60;
evaporation in, 323;
in trade wind belts, xiv, 355-6, 380;
irrigation by sun-power, v, 178;
lizards of, xii, 206;
mirages, i, 172-3, 174, iv, 328-9;
rainfall, i, 112;
rainfall and plants, xiii, 377-81;
rock weathering in, iii, 23, 71-3, xiv, 42, 77, 79;
salt deposits, viii, 197;
"stretching" of, xi, 173;
water-storing plants, xiii, 28, 30, 41-2, 104, 106-7, 336 (illus.);
wind action in, iii, 71-5
(see also Arid Regions)

Desert Sounds, i, 196, 371

Desert Topography, xiv, 41-2

Design, elements of (prehistoric), xv, 299

Designs, enlargement of by lanterns, iv, 342

Desires, suppression of, xi, 140-2
(see also Suppressions)

Despondency, indigestion and, xi, 370
(see also Dejection)

Detectors, wireless, iv, 315-16, vii, 261, 268-70, 278-80;
to guide ships, 284-5

Determiners, inheritance, ix, 329-42, x, 233-4, xiii, 330, xvi, 156

Detonation, of explosives, viii, 262

Detroit, steamers passing, xiv, 212

Devilfish, xii, 78, 148-50

Devil's Tower, Wyoming, iii, 111, 176 (Pl. 10), xiv, 129-30

Devil Whirlwinds, i, 60, 371

Devonian Period, iii, 20, 194-6, 378;
"Age of Fishes," 283, xv, 71;
animals and plants in, iii, 252, 271, 277, 278, 282-4, 285;
extension of sea in, 192 (fig. 37)

De Vries, variation studies, xvi, 153

Dew, i, 120-1, 371, xiii, 108;
former belief about, i, 119;
not formed on cloudy nights, iv, 183

Dewar, liquid air inventions, i, 31, vii, 323

Dewar Flask, viii, 68

Dew Bow, i, 177

Dew Point, i, 78, 79, 371

Dew Ponds, i, 352-3, 371

Dextrin, viii, 227-8;
in bread crust, 368;
molecules of, 356;
production and uses, 241, 243, 244

Dholes, xii, 345

Diabetes, ix, 290, 293-4, x, 276, 330

Diablerets, peaks of, xiv, 202

Diagnosis, art and science of, x, 366-79;
Brown's system, 89;
chest, 99, 371;
Egyptian study of, xvi, 70;
of infectious diseases (serum method), x, 215-17;
X-rays in, vii, 251, 254, 255, 256, x, 185-6, 372-4

Diamond Drills, v, 263, 264, 380;
in ancient Egypt, xvi, 67

Diamonds, iii, 328, viii, 42-3;
artificial, vii, 301, 311, xvi, 190;
cathode ray effects, 193;
cutting of, vii, 300, 309;
electrification, vi, 12;
in meteorites, ii, 292;
X-ray tests, vii, 257

Diana of the Ephesians, ii, 284

Diarrhea, ix, 249, x, 253, 307, 328

Diastole, arterial, x, 62, 63-4, 65;
of heart, 65

Diathermanous Bodies, iv, 182

Diatoms, deposits of, iii, 257-8, xiii, 67-8;
in tripolite, iii, 335;
in sea, xii, 17;
oil from, iii, 349;
oil storage by, ix, 28

Diatonic Scale, iv, 207

Dichloramin-T., x, 183, 382

Dicotyledons, xiii, 60;
antiquity, 207;
leaves and flowers, 176, 178;
leaves and stems, 177 (fig.);
subdivisions, 180, 189-90;
various families, 189-205

Dictation, memory after-images in, xi, 220

Dieffenbach, Johann Friedrich, x, 130

Dielectric, of condensers, iv, 264, vi, 302, 305, vii, 366;
in lightning, 206;
losses due to imperfect, 297-8;
strain, 366

Diesel Engines, v, 161-2, 382;
efficiency, 164;
fuel, 156;
in submarines, 199

Diet, bile in relation to, ix, 275;
deficiency of, diseases from, x, 255-68, 276;
fads of, ix, 285-6;
fats and proteins in, 300-1;
for reducing weight, 301-2;
mixed, man adapted to, 246, 285-6;
natural regulation of, 301, x, 255, 257;
need of amino acids in, 278;
nutrients in daily, viii, 366-7;
starch foods in ordinary, ix, 290, 300
(see also Foods, Nutrition)

Difform Motion, ii, 80

Diffraction of light, iv, 326, 378;
optical phenomena, i, 183-5

Diffraction of sound, iv, 52, 236-7

Digestion, ix, 226-46, x, 319-30, 353;
benefited by savory food, ix, 98, 241-2;
chemistry of, viii, 356-8;
color effects, xi, 96;
emotion effects on, ix, 165, 241;
enzymes in, viii, 103, 357 (see Enzymes);
excitement effects, xi, 374-5;
exercise and, 339;
fried foods and, ix, 286;
fruit stimulation of, viii, 365;
glucose in, 225-6;
historical studies of, ix, 239-40, x, 121, 128;
hot baths and, ix, 313;
in men and plants, xiii, 109;
of proteins, x, 204;
sleep in relation to, ix, 219, xi, 285;
soups as aid to, ix, 241, x, 320
(see also Indigestion)

Digging with water jets, v, 88

Digitalis, source, xiii, 256;
use of, in heart diseases, x, 333, 383

Dikes (geological), iii, 13, 110-11, 378, xiv, 106-8;
columns in, 130;
illustrations, iii, 102, 160 (Pl. 9);
veins and, 383-4

Dilated Stomach, ix, 85

Dimension, illusions of, xi, 186, 188, 189;
perception of, 162, 165, 171-2, 172-83

Dining rooms, lighting, vi, 275-6, vii, 69-70

Dinosaurs, iii, 288-93, 304 (Pl. 17), xii, 182, 194-5

Diœcious Plants, xiii, 47

Dionysus, worship of, xv, 352

Diophantus, xvi, 95

Dioptra, of Ctesibius, xvi, 91

Diphenyl, viii, 240

Dipper (constellation), moving clusters in, ii, 343

Diphtheria, x, 296-8;
antitoxin of, 197, 212, 213-14, 218, 296-8;
immunity to, 207, 298;
named by Bretonneau, 110;
toxin of, 196, 197

Direct Current Generators, iv, 307-8, vi, 159, 175-94, 344;
commutators on, vii, 364-5;
employment, vi, 215;
voltages, 159

Direct Current Motors, vi, 217-39;
in traction, vii, 182-3, 198-200;
on farms, 224;
speed flexibility, vi, 224-6, 229, 230, 232, 240-1

Direct Currents, vi, 152, 153-4, vii, 365;
ammeters for, vii, 166-72;
circuit-breakers for, 37, 39, 40;
conversion from alternating, vi, 330-48;
generation (See Direct Current Generators);
inductance in, 166;
lighting and magnetic effects, 155, 156-7;
open-circuited by condensers, 170, 304;
power consumed by, 165;
transformers unusable, 309;
transmission by, 160, 161, 195, 332;
uses, 152, 332;
used in electric furnaces, vii, 305-6;
used in electrochemistry, vi, 163;
used in electrotherapy, vii, 244;
used in smoke precipitation, vi, 164;
used in traction, 161-2, vii, 182, 186, 195;
value of current flow, vi, 164-5 (see Ohm's Law);
voltages, vii, 164;
voltages, production of high, 349-50;
voltmeters for, 154-65;
wattmeters for, 172, 173, 175

Direct Lighting, xi, 277, 373

Direction, perception of, ix, 117-18, 120, xi, 165, 167-71

Directional Wireless, i, 291, 302

Dirigible Balloons, iv, 107-8, v, 226-30, 382;
in forest service, i, 49

Disaccharides, viii, 224, 226-7, 375;
enzyme of, 357

Discomfort, atmospheric, i, 318, 320, 322;
senses of, in infants, ix, 351

Discordant Coasts, xiv, 249

Discouragement, conquering of, xi, 337-40
(see also Dejection, Despondency)

Discoveries, accidental, xv, 212-13, 232, 241-2;
great, usual way of, x, 40;
priority in scientific, 122

Disease Germs, x, 193-226, xiii, 71;
body resistance to, ix, 177-9, 185-7, x, 197-8, 203-12, xi, 34;
campaign against, x, 285-315;
discovery of, x, 194, 381, xvi, 143;
identification of, x, 150, 215-17;
in air, danger from, i, 325-6;
in sewage, viii, 326, 328;
in water supplies, 41, 318, 319;
man's struggle with, xv, 25-6;
"portals of entry," x, 198, 201-2. (See also Infectious Diseases)

Diseases, anciently ascribed to spirits, x, 12;
atmospheric electricity and, i, 330;
"atom" theory of, x, 26;
Brunonian theory of, 89;
causes and factors other than infection, 227-81, 283;
causes of infectious, 193-226;
causes of, historical conceptions, 380;
climatic treatment, i, 331, x, 383;
diagnosis, (see Diagnosis);
electric treatment (see Electro-therapeutics);
habit in, xi, 248;
Hoffmann's nervous fluid theory, x, 85-6;
Humoral Doctrine of, 21;
hypnotic treatment, xi, 319;
infectious (see Infectious Diseases);
James on, x, 244;
lesion differentiated from, 98;
living causes, 193-226;
Locke on curing of, 75;
manifestations of, in organs, 318-65;
mechanical theory of, 23, 70, 71;
mental, 354-65;
mental factors in, 242-4;
metabolism, effects of, ix, 179, 302-4;
nature in cure of, x, 21, 73, 75-6, 84-5, 367;
occupational, 244-6;
Paracelsus on causes of, 48-9;
pneumatic theory, 26-7, 29;
prevention of, 282-317, xv, 49;
Pythagorean theory of, x, 18;
racial susceptibility to, xv, 47-52;
recognition of, x, 366-76;
savage conceptions and treatment, xv, 352-3, 359;
solidistic theory, x, 25-6;
specific, 196;
sthenic and asthenic, 89;
spread by tainted water, xiv, 140;
suppressed emotions and, xi, 140, 141;
Sydenham on meaning of, x, 73;
Sylvius's chemical theory of, 69;
thirst unimpaired in, ix, 89;
treatment of, x, 379-84
(see also Therapy);
tropical, xiv, 356-7, xv, 49-50;
Van Helmont's conception of, x, 68;
(see also Disease Germs)

Disgust, in various sentiments, xi, 146, 148

Disinfectants, viii, 332-3;
chlorine, 86, 274, 333;
formaldehyde, 219, 333;
hydrogen peroxide, viii, 41;
mercuric, 170, 333;
ozone, vii, 354;
sulphur dioxide, viii, 78, 333

Dismal Swamp, coal-forming conditions in, iii, 199

Displacement Currents, vi, 302, 305

Display Lighting, vi, 280, vii, 339-43;
colors in, iv, 51;
psychology of, xi, 344, 345, 346

Dispositions, sour and sunny, xi, 55

Dissection of human bodies, x, 30, 41-2, 45, 81

Dissociation, chemical, viii, 120, 121, 122, 375

Dissociation of Ideas, xi, 206, 209;
in mental troubles, x, 355, 360-1, 365

Distance, method of measuring, ii, 197-8;
perception of, ix, 118-19, 120, xi, 165-9, 173-89;
units of, iv, 283

Distance Senses, ix, 86, 96-121;
choice in relation to, 121, 140;
connections with brain, 142

Distillation, alcoholic, viii, 249-50;
apparatus, 213 (fig.);
fractional, i, 32, iv, 168

Distillation of coal, vii, 252-3

Distractions, fatigue from, xi, 277

Distress Signals, vii, 284

Ditch Grass, fertilization, xiii, 151-2

Ditching Machines, v, 216, 253, 254-5

Divers, compression and decompression, v, 120-1;
pressure on, i, 329

Diversion, need of, in brain work, ix, 138

Diving Bells, v, 115-16, 121

Divining Rods, iii, 123-4

Division of Labor, first form of, xv, 279;
in plants, xiii, 61-2

Divorce, xv, 290-1

Dizziness, from over-ventilation of lungs, ix, 266-7;
sensation of, xi, 64

"Doctor" Winds, i, 131, 371

Dodder, plant, xiii, 100, 101 (fig.)

Dodo, xii, 265

Dog Family, xii, 338-46

Dogfish, xii, 143, 146;
eggs of, 140;
name changed, i, 224

Dogs, xii, 344-6;
baboons and, 380;
canine teeth of, 333;
cat's hatred for, origin of, 355;
domestication of, xii, 345-6, xv, 197, 198;
embryological resemblances, 54;
employment in hunting, 223;
expression of emotions by, 64;
heat-loss regulation by, ix, 307-8;
hyenas and, xii, 351;
imitation in, xv, 66;
language methods of, 141;
mode of attack, xii, 354;
reasoning power in, xv, 68;
sense of smell in, ix, 97, 117;
wild, xii, 344-5;
zoölogical interest, xvi, 16

Dogwood, xiii, 271;
flowering, 45;
index plant, i, 255

Doldrums, i, 127, 129, 136, 371, xiv, 348, 349

Dollond, telescopes, ii, 100, 103, xvi, 125

Dolomite, viii, 149;
in refractories, vii, 307

Dolphins, xii, 297

Domestic Animals, development of, xii, 345-6, xv, 197-8

Dominants, in crosses, ix, 334, 335, x, 231, 233

Donati's Comet, ii, 275, 277, 280-1

Donkeys, xii, 308

Door-checks, pneumatic, v, 134

Doppler's Principle, ii, 119, iv, 209-10;
astronomical applications, ii, 123, 129, 133, 363

Dormice, xii, 291

Double Decomposition, viii, 104-5, 375

Double Images, xi, 175-81

Double Stars, ii, 122-4, 334-5;
colors, 296;
connections, 340;
proportion of, 320;
telescopes required for, 97-8;
theory of origin, 377
(see also Binary Stars)

Doubt, reasoning and, xi, 239-40;
retardization of impulses in, 20

Douglas Fir, forests, xiii, 340, xiv, 374

Dover, England, breakwater, xiv, 301

Doves, mating of, xv, 276;
plumage of neck, xii, 245
(see also pigeons)

Down, character of, xii, 244;
warmth of, x, 309

Downs of England, dew ponds, i, 352-3

Dowry System, xv, 285

Dragon Flies, xii, 105-6;
ancient, iii, 279, xiii, 308;
eyes of, xii, 102

Dragon Tree, xiii, 183-4

Drainage Systems, continental, xiv, 189-90;
development stages, iii, 33-4, xiv, 48, 49, 155;
earthquake effects, 335;
Ice Age changes, iii, 243-5, xiv, 60-1, 170-1;
joints and, 131

Drake, Daniel, x, 116

Drama, origin and development of, xv, 303-10, 322, 325;
sentiment in, xi, 151

Draper, Dr. Henry, astronomical work, ii, 17, 114, 116, 126, 130, 134,
135, 307, 358;
reflectors of, 103, 106

Draper Catalogue of Star Spectra, ii, 116-18, 146, 307, 309, 310

Dravidians, of India, xvi, 53

Drawing, development of art of, xv, 296, 298-9

Drawing Rolls, Arkwright's, v, 273-4, 376

Dreams, xi, 292-302;
images of, 221;
primitive conception of, xv, 328-9, 358;
psychoanalysis of, x, 364-5

Dredges, modern, v, 255-9, 381;
walking-machine, 216

Dried Foods, viii, 371;
antiscurvy vitamines in, x, 262, 266

Drift, Glacial, iii, 378 (see Glacial Debris)

Drills, ancient Egyptian, xvi, 67;
core, v, 263;
diamond, 263, 264, 380;
metal-cutting by, 47;
multiple, 53 (see Multiple Drills);
oil, v, 265-7;
pneumatic, i, 27, iv, 129, v, 129-30, 261-2, 263, 380, 381;
rock, 129, 261-2;
sonic-wave, 108;
spiral chisels, 46

Dropsy, polyuria in disappearance of, x, 344;
Van Helmont's idea of, 68

Droughts, i, 79, 371;
financial panics and, 263;
records of, in tree rings, xiii, 25;
springs and wells in, xiv, 136, 138

Drowned Valleys, iii, 37, 378, xiv, 40, 164, 255-6;
as harbors, 268

Drugs, blood riddance of, ix, 274;
coal tar, viii, 253;
in mother's blood, effects, ix, 343-4;
plant sources, xiii, 249-55;
pure food law on, viii, 370;
taste deadening by, xi, 72;
use of, in medicine, x, 21-2, 22-3, 30, 44, 45, 75-6, 77-8, 380-1,
xvi, 109, 186-7

Drumlins, iii, 69, xiv, 60

Drums, xv, 316;
African, 313 (fig.)

Drupes, xiii, 54, 194

Dry Cells, iv, 297-8, vi, 59, 126, 127, 138, 143-4

Dry Docks, floating of ships in, v, 95

Dry Fogs, i, 96, 371;
of 1783, 57, 58-9

Dry Fruits, xiii, 54, 55-6, 57

Drying Machines, iv, 73

Dry Steam, v, 140

Duckbills, xii 272, 273

Ducks, xii, 257-8;
darkness effects on, x, 253;
primitive methods of hunting, xv, 222

Duckweed, xiii, 31

Ductless Glands, x, 346-53;
secretions used in therapy, 382

Dufrausne, x, 181

Duluth, Lake, iii, 149

Dunes, i, 53, iii, 71, 74

Duplex Telegraphy, vii, 112, 114-17, 376

Dupuytren, Guillaume, x, 130

Duralumin, v, 228

Duryea, Charles E., v, 213

Dust, atmospheric, i, 52-65;
atmospheric, elimination methods, ix, 269;
body handling of, 223-4;
deep sea deposits, iii, 54-5;
effects on light, i, 165, 183;
electric precipitation, vii, 216, 301-2, 347;
in cloud formation, i, 91;
in fog formation, viii, 304;
in stratosphere, i, 20, 144;
meteoric (see Meteoric Dust);
methods of measuring, i, 61-3;
physiological effects, i, 325;
volcanic (see Volcanic Dust);
wind-carrying of, i, 52-5, iii, 71, 73, 75, xiii, 344

Dust Count, Chicago standard, viii, 332

Dust-counter, i, 62, 371

Dust Whirlwinds, i, 60

Dusty Trades, i, 325

Dutch Language, relations of, xv, 160, 162

Dutchman's-pipe Vine, xiii, 131-3

Dyes, Dyeing, ancient Egyptian, xvi, 72-3, 74;
antiquity of use, xiii, 210;
chemistry of, viii, 258-60, xvi, 163;
coal tar, viii, 253-4;
importance of industry, 253-4;
purple, sources of, xii, 68, 72

Dynamic Electricity, vii, 367

Dynamic Heating and Cooling, i, 90

Dynamic Meteorology, i, 123, 371

Dynamite, viii, 261;
blasting with, v, 100;
invention, 380

Dynamo-Electric Machines, defined, vii, 367

Dynamometer, iv, 102, vii, 367

Dynamos, iv, 306-8, vi, 49-56;
discovery of principle, 22, 50;
function, 72;
Gramme's, 26;
interchangeability with motors, discovery of, iv, 54;
invention and development, xvi, 189;
parts, vii, 367;
pole pieces, 374;
separate and self-excited, vi, 186-7;
source of energy, 129;
submarine, double uses, v, 199;
voltage, on what dependent, vi, 131
(see also Generators)

Dynamotors, vii, 136-7

Dyne, unit of force, iv, 69-70

Dyrenforth, Gen. Robert, i, 338

Dysentery, amoebic, x, 195, 199;
from water pollution, viii, 318;
in tropics, x, 251, xv, 50;
overheating and, x, 307

Dyspepsia, from tight lacing, x, 309;
mental effects, xi, 369-70

Dysprosium, atomic weight and symbol, viii, 383

Eads, Captain, Mississippi River jetties, xiv, 270

Eagles, xii, 260, 261;
bald-headed, unions among, xv, 277

Earache, in children, ix, 104

Ear-mindedness, xi, 222

Ears, ix, 100-3, xi, 98-102;
basilar membrane of, iv, 203;
cartilage in, ix, 57;
direction perception by, 117, xi, 167-9;
disorders and care of, ix, 103-4;
equal size of, 169-70;
equilibrium organs in, 89-90;
hearing by, iv, 203-4 (see Hearing);
infections of, ix, 61-2, x, 219;
limits of hearing power, iv, 204, ix, 99, 100;
liquids of inner, iv, 203;
movements of, in animals, ix, 82, 117;
mutilations of, by savages, xv, 259;
nerve connections, ix, 124, 142, 143 (fig.);
origin, xi, 109;
outer, in hearing, ix, 117;
reddening of, in cold, 311;
receptor organs, attunement, xi, 62;
ringing in, iv, 203;
sensitiveness of, 204, 211-12, 360;
static sense organs in, xi, 126;
temperature of, ix, 93

Ear Trumpet, iv, 239

Earth, agonic lines of, iv, 246;
ancient ideas, xvi, 58;
antiquity, iii, 21, 43, 201, 218, xiii, 306, 314, 322, xiv, 29, (see
also Geological Ages);
axis mutation, discovery, xvi, 124;
center of universe, ii, 9 (see Geocentric Theory);
centrifugal force of, iv, 75;
changeableness of features, iii, 9-12, xiv, 3-4, 15-16, 28-30;
changes in historic times, xv, 72;
chemistry of, viii, 190-203;
climate in past ages (see Climate);
comets in relation to, ii, 279-80;
crust (see Crust of Earth);
density and specific gravity, iv, 98, 164, xiv, 11;
diameter, ii, 64, 192, iii, 51;
diameters, equatorial and polar, iv, 101, xiv, 9;
electrification, i, 144, 145-6, iv, 269, 270, vii, 207, 209-10, 212-13;
energy sources and losses, ix, 25-6;
geological history, iii, 164-248, xv, 70-1, 72-6;
gravity of, iv, 98-9, 101;
heat from sun, amount of, 194;
heat radiation and protection, 183-4;
Hindu conception, ii, 36;
interior, heat and condition, iii, 107-8, 120-1, 160, 162, iv, 164,
xiv, 11-17, 312;
internal heat utilized, v, 178-81, ix, 25, xiv, 15;
internal waters, 151;
land and water distribution, 20-7;
life on, antiquity of, xv, 71;
life on, beginnings, xiii, 298-304;
life on, conditions necessary, ii, 242-5;
life on, origin of, xii, 9-13;
magnetic axis, iv, 250;
magnetic field and lines of, 252-253;
magnetic poles, 246, vi, 29-30;
magnetism, ii, 178, 186, iv, 248-50, vi, 12, 29, 39-40;
magnetism and internal iron, xiv, 11;
magnetism in relation to aurora, i, 159-61;
man's machining of, v, 251-67;
mass of, iv, 98;
motions (see Revolution, Rotation);
origin, ancient ideas, ii, 366-7, xvi, 77, 78;
origin, modern theories, ii, 373, iii, 158-63;
rigidity, 107-8, xiv, 17;
sciences of, xvi, 36;
shadow in space, ii, 206;
shape, 59, 69, 71, iv, 101, xiv, 9;
shape, ancient ideas, ii, 10, 28, 30, 34-5;
shrinking of, iii, 83-4, 108, 160, 162;
size, ii, 162, 163;
surface features, xiv, 9-11;
temperature layers, 13-15;
temperature ranges and control, ii, 243-4;
temperature regulation by atmosphere, iv, 183-4;
water circulation and supply, xiv, 134-5, 151;
waters, past and future, ii, 244;
waters within, iii, 109-10, 113-29;
weight, ii, 68-9, 76, iv, 98, 164;
wind and pressure belts, i, 128-9

Earth-Air-currents, i, 145, 371

Earth Movements, xiv, 32, 33-9;
importance to human life, 341

Earthquakes, iii, 92-8, xiv, 330-43;
faulting in, 39, 115, 128;
lakes formed by, 203;
submarine effects, 284;
water table affected by, 136

Earthquake Waves, transmission of, xiv, 17, 332-3

Earthworms, xii, 51-3;
power of distinguishing light, ix, 105

Earwigs, xii, 107

East Africa, ancient dinosaurs of, xii, 195;
clan ceremonies in, xv, 363;
development of, 136;
glaciers in, xiv, 54;
Great Rift Valley, 118-20, 121;
lava fields and volcanoes, 103, 317

East Indies, animals of, xii, 145, 288, 352, 353, 359, 362, 370;
beriberi in, x, 257;
chocolate growing, xiii, 234;
land and sea breezes, i, 131;
nautilus of, xii, 75;
nutmeg production, xiii, 261-2;
Portuguese and Dutch in, xiv, 310;
rattan palm of, 368;
smallpox inoculation in, x, 207;
spices from, xiii, 259;
wild arum of, 153

East River, pipe-thawing under, vii, 338-9

Eastport, Maine, tide at, xiv, 293

Eating, effect of excitement during, xi, 374-5;
kinaesthetic sensations in, 127;
metabolism increased by, x, 271;
obesity and, 273

Eccentric, of steam engine, v, 40-1

Echidnas, xii, 272-3

Echinoderms, iii, 259, 268-70, xii, 48-50

Echoes, iv, 237-9;
aerial, i, 190, 193

Eclipses, ancient studies of, ii, 9, 32, 37;
annular or ring, 214;
elements of, 216;
of Jupiter's moons, 263;
of moon, 206-8;
of sun, 209-18
(see also Solar Eclipses)

Ecliptic, ii, 162, 350;
plane of, 70, 163;
poles of, 92;
trepidation of, 38

Ecology, xiii, 354-7

Economic Botany, xiii, 208-66

Economic Geology, iii, 342-76, xvi, 172-4

Ectoderm, xii, 26

Ecuador, glaciers in, xiv, 54;
yellow fever in, x, 160, 172-3

Eddies, wind, i, 292, 294, 371

Eddington, astronomer, ii, 17, 330, 341, 342, 347, 348-9, 354, 356, 382;
quoted, 151, 320, 344, 384;
"Stellar Movements," 319

Eddy Currents, vi, 192, vii, 365-6;
in various machines, vi, 213, 225, 316

Edinburgh University, medical school, xvi, 179

Edison, carbon lamp, v, 381;
carbon lamp filaments, xvi, 189;
carbon microphone, v, 381;
early dynamos, xvi, 188;
electrical work, vi, 26;
father of electric lighting, vi, 265;
first incandescent lamp, xvi, 188;
kinetoscope, v, 330;
phonograph, 328, 381;
quadruplex telegraph system, vii, 112;
storage battery, vi, 149-51;
vacuum tube discovery, vii, 276;
Edison Closed Circuit Cell, vi, 137

Edison Electric Company, load factors, vi, 381-2;
storage battery reserves, 382-3;
tied with Interborough System (N. Y.), 384

Edison-Lelande Cell, vi, 139-40

Edison Storage Battery, vi, 130, 149-51

Education, association principle in, xi, 200-1, 203, 204;
botanical, xvi, 22;
environment in, xi, 249;
grasping reflex, importance, 43;
hygienic, x, 282-5;
imitation in, xv, 66-7;
importance of choices in, xi, 266-7;
language and, xv, 145-6;
modern, a summary of past, 145-6, 164;
modern, beginnings, xvi, 111;
necessity of, ix, 344, 352;
progress in relation to, xv, 30-1, xvi, 47;
reaction speeds, xi, 158, 159;
sensation as, 68;
Spencer on, x, 282, 284;
waste of time in spelling, xv, 177;
(see also Learning Processes)

Eelgrass, fertilization, xiii, 150-1

Eels, xii, 162-3;
vinegar and paste, 45

Effector Neurones, xi, 21, 22, 26;
in embryo, 34

Efficiency, human, viii, 367, ix, 296, 306;
climatic effects, x, 238-9, xiv, 357, xi, 369-82;
temperature effects, i, 323-4

Efficiency, industrial, xi, 360, 362, 363

Efficiency of Machines, iv, 192, vi, 214, vii, 367;
electric lamps, vi, 268;
generators, 357, 379;
heat engines, highest attainable, iv, 192;
motors, vi, 228;
power plants, 380-3;
transformers, 317-18;
various kinds of engines, v, 155, 161, 164, 170, 172

Egg Cells, production and development of, ix, 332-3, 335, 339, 343-4

Eggs, albuminuria from eating of, x, 345;
amino acids in, 278;
boiling of, viii, 368;
boiling of, on mountains, iv, 170;
calories in, ix, 299;
composition and use, viii, 364;
poisoning from, x, 212;
vitamines in, viii, 369, ix, 33, x, 260, 261;
white of, composition, ix, 176;
white of, digestion of, 233

Egrets, xii, 244, 255

Egypt, antiquity of civilization in, xiv, 196, xv, 84;
bats of, xii, 371;
buffaloes in, 329;
cats of, 355;
geographical changes in, xiv, 33;
lions of, xii, 359;
locust plagues, 109;
Nile inundation, xiv, 70-1;
Nile valley fertility, 53, 71, 219;
Pyramids (see Pyramids);
rock weathering in, xiii, 23, xiv, 78-9;
snowfall in Lower, i, 210;
storks of, xii, 255;
ziczac of, 263

Egypt (Ancient), agriculture, xiii, 210;
astrology and astronomy, ii, 21, 23-6, xv, 269-70, xvi, 69, 70, 71;
baboons in, xii, 380-1;
brick-making in, xv, 267 (fig.);
calendar, xvi, 70;
civilization conditions, xv, 123, 127;
crocodile in, xii, 199;
dogs of, 346;
donkeys in, 308;
duck-hunting in, xv, 222;
hairdressing in, 255 (fig.);
history and civilization, xvi, 53, 65-75;
humped cattle of, xii, 330;
hunting dog of, 345;
irrigation methods, iv, 27 (fig.), v, 18-19, 178, xv, 240;
machines, v, 42;
medical science, x, 11, 12, 31, xvi, 82;
monuments and temples, ii, 24-6, 165;
musical instruments, xv, 314, 317, 318, 319;
papyrus, v, 289-90;
peoples, xvi, 64-5;
plague of blood, i, 358;
poppy cultivation, xiii, 253;
pottery-making in, xv, 249-50, 251 (fig.);
sacred ibis of, xii, 255-6;
sacred ichneumons of, 352;
sailing vessels, v, 182;
sciences, xvi, 54-75, 77, 96;
scribes of, xv, 177 (fig.);
slavery in, 378-9;
spinning and weaving in, 243, 244, 245, 246 (figs.);
stone-cutting in, 271 (fig.);
stone-moving in, 270-1;
sun-worship, ii, 20, 23, 24, 25-6;
tops, v, 339;
water clocks, 58-62;
weapons of, xv, 211 (fig.);
wheat in, xiii, 210;
wheel in, v, 18-19

Egyptian Art, xv, 300-2;
no perspective in, xi, 181

Egyptian Comet, ii, 134

Egyptians, ancient and modern, xvi, 65;
ideas of cosmos, 77;
ideas of insanity, x, 356;
in Mediterranean group, xvi, 49;
not seamen, xiv, 265, 306-7;
scarabs of, xii, 123

Ehrlich, Paul, "atoxyl" of, x, 169;
chemotherapy founded by, 381;
immunity theory, 209, 211-12

Eiffel Tower, hail rods, i, 342, 344;
horizontal rainbows seen from, 177

Einstein Theory, ii, 79-82, xvi, 196-8;
æther constitution and, vii, 368;
anticipations of, xvi, 85;
Newtonian system and, iv, 18

Elands, xii, 327

Elasmosaurus, xii, 202

Elastic Cords, vibrations, iv, 216

Elasticity, iv, 35-6, 156-9;
molecular, perfect, viii, 24;
temperature effects on, iv, 198;
vibration dependent on, 198, 213, 215, ix, 98, 100-1

Elation, in various sentiments, xi, 140, 150

Electrical Capacity, iv, 267-8

Electrical Conductors (see Conductors)

Electrical Machinery, remote and automatic control, vi, 99-101;
ratings, 192-4, 212, 317

Electrical Protective Devices, vii, 32-50

Electrical Terms, vii, 361-76

Electrical Units, iv, 284-5

Electric Arcs, direct currents best, vi, 332;
extinguishing of, 102;
Faraday's experiments, xvi, 189;
heat of, iv, 312, vi, 348;
heat and light, 280;
on alternating circuits, vii, 208-9;
used in nitrogen production, 323-4 (see Arc Process)

Electric Batteries (cells), iv, 271-3, 295-300, vi, 58-62, 126-51, vii,
363;
chemical action, viii, 167-9;
defined, iv, 381, 382;
depolarization, vii, 366;
direct currents, vi, 154;
direction of currents, 59;
function, 72;
invented by Volta, 18-19;
local action, vii, 361;
polarization of, iv, 296, 298, 383;
primary and secondary defined, iv, 383;
used in electrotherapy, vii, 241-4
(see also various kinds of batteries and cells)

Electric Bell, iv, 290-2, vi, 99, 127, 138, 144, 306

Electric Breeze, vii, 238-9

Electric Cars, circuit-breakers in, vi, 101-2;
construction, types, and operation, vii, 182-6;
former and present feeling about, 75-6;
growth and improvement, 180;
movement on hills, vi, 232-3 (see Electric Traction)

Electric Clocks, v, 74

Electric Currents, vi, 67-85;
alternating and direct, 152-3 (see Alternating, Direct Currents);
attracting and repulsion of, 20-1;
cause of, iv, 265, 271, 273, vi, 46, 72;
detection, 91;
direction, 54-7, 59, 124;
distribution (see Power Transmission);
effects on human body, vii, 246-9;
electron theory, vi, 123, 152, vii, 366;
flow, vi, 46, 47, 67-9;
follow least resistance, 96;
Galvanic Faradic, and Franklinic, vii, 242, 243, 245;
heat and light production by, iv, 310-12, vii, 337-8;
induced, iv, 303-8, vi, 22 (see Induced Voltages);
intensity, vii, 370;
leakage, 371;
magnetic effects of, iv, 273-9, 286-7, vi, 20-1, 88-91;
measured by ammeters (see Ammeters);
overloading lines, vi, 9, 72;
production, 46, 72
(see also Dynamos, Electric Batteries, Thermal Couples);
protection against overloading, vii, 34-50;
selenium control valve, v, 332;
surges, vii, 16-18;
units and measurements, iv, 277-85, vi, 69-76, 82, 84-5;
values, effective and maximum, 346-7;
value in oscillating circuits, vii, 289-90;
velocity, Watson's study, xvi, 123;
wire capacity table, vii, 58

Electric Discharges, iv, 264-5, 267, 269, vii, 366;
atmospheric, i, 157, 158-62;
fog dispersal by, 94;
in vacuums, iv, 317-18;
nitrogen fixation by, viii, 73, 74, 346;
rain-making by, i, 340;
through gases, vii, 216, 301-2

Electric Eel, vi, 16, 64, xii, 160-1

Electric Energy, vii, 368;
conversion into heat, 89, 303-5;
due to difference of potential, iv, 263, 264, 265;
equivalents, vii, 382;
transmission (see Power Transmission);
unit of, vi, 82;
unit (joule), iv, 284, 294, 310, 312, vii, 370

Electric Fans, vii, 76-7, ix, 317

Electric Fishes, catfishes, xii, 161;
electric eel, 160-1;
torpedo fish, 149-50

Electric Furnace, iv, 312, vii, 302-12;
history and uses, xvi, 189-91;
invented by Acheson, vii, 301;
operation and products, viii, 283-4

Electric Hammer, vi, 94

Electricity, iv, 256-321 vols. vi, vii;
advantages in home and industry, vii, 51-2;
animal (see Animal Electricity);
atmospheric, i, 141-63, vii, 201-19, 362;
attraction and repulsion law, iv, 256-8, 261, vi, 18, 122;
basis of matter, iv, 23, vi, 107-8, 113, 118 (see Electron Theory);
battleship applications, vii, 325-35;
chemistry and, viii, 164 (see Electrochemistry);
commercial units, iv, 312;
conductors and nonconductors, 258-9, vi, 294-5 (see Conductors,
Nonconductors);
daily applications, xvi, 19, 20, 26-7, 30;
defined, vii, 367;
disadvantages in mines, v, 129;
farm uses, vii, 220-34;
flow, vi, 46, 67, 292-3;
flow, direction of, iv, 265, vi, 56-7;
frictional (see Frictional Electricity);
history of development, iv, 52-5, vi, 9-26, xvi, 121-3, 188-92;
home applications, vii, 73-90;
identity of kinds, vi, 23;
importance of understanding,
9-10, 64-6;
late discovery and use, vii, 235;
lightning and, vi, 10-11, 13-16;
magnetism and, iv, 257, 276, vi, 12, 19-20, 21, 27-8, 86;
"messenger" of physics, iv, 50;
miscellaneous applications, vii, 336-59;
name, origin of, iv, 256, vi, 12;
not made, but moved, 46, 49, 72, 128;
origin, latest views of, 105-25;
physical effects of, x, 250, 254, xi, 117;
popular applications of, iv, 10;
positive and negative, i, 141, 142, iv, 258, 265, vi, 287;
precise measurements, vii, 152;
production of (see Electric Batteries, Generators, Power Plants);
production by wind power, i, 38, v, 173;
quantity unit, iv, 261, 277, 280, vii, 365, 374;
science of power, xvi, 36-7;
single-fluid theory, vi, 11, 288-93;
static (see Static E.);
transmission (see Power Transmission);
uses and power, vi, 10;
use in medicine (see Electro-therapeutics);
wave lengths and frequency, vii, 260;
wide familiarity with, 152-3;
widespread interest in, vi, 330-1 (see further Electric Currents,
Electric Power, Electromotive Force, etc)

Electric Lamps, iv, 310, vi, 265-8;
candlepower of, iv, 352, xvi, 189;
detonation on breaking, vii, 211;
Edison's inventions, xvi, 188, 189;
energy requirements, iv, 311;
light and heat, vi, 268;
neon and argon fillers, i, 33;
number used, vii, 51;
short-circuiting by burning out, 35

Electric Lighting, vi, 264-83;
advances in applications of, iv, 50-1, vi;
direct and alternating current effects, 155-6;
due to glowing of a solid, viii, 60;
farm uses, vii, 231, 232, 233;
fire hazard reduced by, vii, 51;
history, xvi, 122-3, 188, 189;
homes and interiors, vi, 275-8, vii, 68-72, 75;
leading inventors, vi, 26, 265;
meter units, iv, 312;
outdoor, vi, 278-80, 283, vii, 339-4;
small fraction of power used in, vi, 381;
wide use and advantages, vii, 51, 52

Electric Locomotives, v, 212, vi, 161, 162, vii, 182;
induction motors in, vi, 249;
motors and currents, vii, 195-6, 200;
power and efficiency, 193-4;
regenerative brakes, 200

Electric Meters, vii, 151-79;
for alternating currents, vi, 346-7;
screening of, 32;
units used in, iv, 312, vi, 82-3

Electric Power, costs, on what dependent, vi, 380-2;
costs for farm work, vii, 224-6;
extra charges for peak hours, vi, 301, vii, 177-8;
measured in watts, iv, 310, 312, vi, 84-5;
transmission (see Power Transmission);
water power and, viii, 283

Electric Pumps, vii, 86-7;
remote control, vi, 99-100

Electric Ranges, vii, 88-9;
special rates for, 174

Electric Traction, vii, 180-200;
block signals, 355;
converters used, vi, 342;
current used, 161-3;
motors used, 231, 241
(see also Electrification of Railroads)

Electric Waves, discovery of, iv, 55, 313
(see also Electromagnetic Waves)

Electric Wiring (see Wires, Wiring)

Electrification, iv, 256-62, vi, 11, 12, 13, 286;
degree of, 17;
methods of, iv, 265-7;
of atmosphere, vii, 207, 212-13, 216-17;
of earth and air, i, 144-6, 150
(see also Charged Bodies)

Electrification of Railroads, v, 212, vi, 162, 249, vii, 181-2, 193-6;
block signal system, vii, 359;
brake system, 200;
smoke relief by, i, 64;
trolley and third rail systems, vii, 197-8
(see also Railroad Terminals)

Electrochemical Analysis, viii, 294-5

Electrochemistry, vii, 299-324, viii, 164-9, 283-4, 312;
organic, 266;
use of direct current in, vi, 163;
water power and, viii, 267

Electrodes, iv, 297, 317, 382, vi, 60, 129, 130-5, 367;
graphite, vii, 308, 309

Electrolysis defined, iv, 382, vii, 367, viii, 375;
industrial applications, vii, 312-24, viii, 164-7, 271, 272, 284;
ionic hypothesis of, viii, 123-5;
of organic compounds, 266;
of water, 30-1

Electrolytes, iv, 382, vi, 23, 58, viii, 376;
acids, bases, and salts called, 125;
action of currents in, vi, 131-5, vii, 247;
don'ts about, vi, 149;
double-fluid, 137;
in primary and secondary cells, 130

Electrolytic Cells, vii, 313, 367

Electrolytic Corrosion, vi, 65-6, vii, 189;
alternating currents and, 305

Electrolytic Dissociation, viii, 123-4, xvi, 164-5

Electromagnetic Units, iv, 278-82

Electromagnetic Waves, form and lengths, vii, 371;
length and frequency, 259, 260;
transmitted by æther, vi, 119, 269
(see also Radio Waves)

Electromagnetism, Electromagnets, iv, 286-94, vi, 30, 31, 86-104, vii,
367, 372;
Einstein theory and, ii, 80-1

Electromotive Force, defined, iv, 271, 294, 382, vi, 46-9;
dangers of uncontrolled, 64-5;
generation, 49-66 (see Electric Batteries, Generators, Thermal
Couples);
induced and generated, vii, 370;
measured in volts, iv, 280-1, 284, vi, 53-4, 57;
phase relations, 167-9, 171-4, 242;
self-induction, vii, 375;
uses, vi, 56
(see also Voltage)

Electromotive Force Waves, vi, 198-200, 208

Electromotive Series, viii, 127-9, 376

Electrons, vi, 113-15, vii, 367;
beta rays, viii, 185, 186;
from sun in upper air, i, 144, 146;
in charged bodies, 142, 143;
in sun, ii, 177-8;
knowledge of, from radioactivity, viii, 307;
motions in light, heat and electricity, vii, 371;
nature, vi, 118, 120;
negative electricity, viii, 187-8;
original study, xvi, 193;
size and weight, i, 141-2, viii, 187;
speed in cathode rays, iv, 318

Electron Theory, iv, 321, vi, 26, 122-5, vii, 366, 367, 371, viii, 187-8;
compared with Franklin's theory, vi, 288, 292;
in various electrical actions, 133-4, 152, 153, 284, 288, 302, 338-9,
340;
Larmor's proposal, xvi, 193

Electroplating, vii, 314-19, 374, viii, 164-6, 284

Electro-Refining, vii, 319-21, viii, 166-7, 284

Electrostatic Fields, iv, 261-2, vii, 368;
intensity of, 370

Electrostatic Generators, vi, 298-301

Electrostatics, defined, iv, 259;
importance of, 271
(see also Charges, Charged Bodies)

Electro-Therapeutics, vii, 235-57, 368

Electrotyping, vii, 313-14

Elements, vi, 108-9, viii, 12, 16, 376, 383;
atomic numbers, 183, 309;
atomic weights (see Atomic Weights);
classification, metals and nonmetals, 17-19, 126, 175-7;
discoveries through Mendeléeff's tables, 180, 181, 182, xvi, 163;
Greek idea of primary, 81, 83;
in earth's crust, iii, 308, viii, 19, 190-1, 192, 194;
in heavenly bodies, 302;
in meteorites, ii, 292;
in sea water, xiv, 295;
in stars, ii, 115-18;
in sun, 114, 128, 185, 211;
isotopic and isobaric, viii, 189;
made up of molecules, 26;
number, 16, 183, 309;
only things man cannot produce, vii, 310;
origin in silicates, viii, 193;
origin, remarks on, 84;
periodic classification, 177-83;
physical state and chemical properties, 297-8;
potentials against hydrogen, vii, 383;
properties dependent on atomic weights, xvi, 134;
Prout's hypothesis of hydrogen basis, viii, 177;
radicals or groups, 93;
radioactive, 184-9;
spectra of, ii, 113, viii, 302;
symbols, 91, 383;
tests of, 285-91;
transmutation of, 188-9, xvi, 14-15;
union types, viii, 20-1, 99-100;
valency, vii, 384, viii, 93, 122

Elephants, xii, 301-4;
breeding and domestication of, xv, 197;
breeding rate, 20;
evolution, iii, 300;
fearlessness, xi, 136;
formerly in Europe, xv, 76, 92;
strength of, 18;
trapping of, 225, 226 (fig.), 227;
trypanosome in, x, 168

Elevation (geological), denudation increased by, xiv, 39, 40;
effects on streams, 163, 164-70, 187-8;
instances of, 33-4;
of coasts, 253, 262;
of ocean floor, xiv, 286
(see also Level Changes, Rejuvenation)

Elevators, air cushioning, v, 134-5;
first passenger, 380;
hydraulic, 102-3;
motors used, vi, 231, 234;
power for fast and slow, 83, 85;
sense of giddiness in, xi, 126-7

Elk, xii, 317, 318

Elm Trees, xiii, 194, 271-2

Embroideries, machine-made, v, 285-7

Embryo, development in man and animals, xv, 54, 55;
development of human, ix, 343-4;
development of nervous system in, xi, 34-6;
flexed form of hand, 42-3;
gill slits and notochord in, xii, 128;
of mammals, 273;
of marsupials, 274;
past stages of race seen in, xv, 53-4;
semiaquatic conditions, xi, 36

Embryo, of plants, xiii, 60

Embryological Development, x, 228 (see Embryo)

Embryology, history, xvi, 107, 156

Emeralds, iii, 325;
oriental, 327

Emergencies, body responses in, ix, 166-7, 171-2, 209, 220, 221, 293

Emerson, metaphor of, i, 187;
on common mind, xi, 152;
on narrowness of men, 376

Emery, iii, 327-8

Emmet, Thomas, x, 122, xvi, 186

Emotional Glycosuria, xi, 138

Emotions, xi, 129-42;
associations
determined by, 205-6;
brain processes in, ix, 154;
classes of, 153-4;
combinations in sentiments, xi, 146-50;
expression of, in men and animals, xv, 63-5, 152;
fatigue and, xi, 274-6;
hypnotic suggestion of, 317-18;
in crowd psychology, 331-2;
not localized in body, 62;
pain and, 119, 120;
physiological effects of, ix, 163-7, 171-2, 200, 209, 240-1, 348, x,
339, 353;
primary varieties, xi, 55-6;
suppression of, 140-2
(see also Suppressions)

Empathy, xi, 172-3, 186;
in advertising, 346-7;
in salesmanship, 335

Empedocles, atomic theory, xvi, 87;
malaria prevention by, x, 154;
on matter, xvi, 83, 118

Empiric Doctrine (medicine), x, 24, 28

Emu, xii, 243, 249, xv, 194

Emulsions, colloidal state, viii, 314, 316, 356;
defined, ix, 289

Encke's Comet, ii, 280;
used to find Mercury's weight, 77

End Buds, of fishes, xii, 137

Endless Screw, v, 38, 37 (fig.)

Endocarditis, x, 195, 332

Endoderm, xii, 26

Endoskeleton, xii, 127

Endothelial Cells, x, 197, 210

Energy, conservation of, iv, 40-1 (see Conservation of Energy);
defined, 13-14, 37-9;
equation of, 78;
force contrasted with, 41;
forms and transformations, 81-8;
future sources of, v, 171-81;
heat equivalent (see Mechanical Equivalent of Heat);
kinetic and potential, iv, 79, 81-5, vii, 368;
matter and, iv, 13-14;
of plants and animals, viii, 334, 335, 336, 347, 349, 350
(see also
Human Energy);
physics as science of, iv, 12, 13-14, 50;
power differentiated from, 80;
radiant (see Radiant Energy);
sources in nature, viii, 267-8, ix, 25-6, xiv, 31-2;
sun as source of, v, 177, viii, 267, 334, 350, ix, 25-6, xiv, 32;
transference and transformation of, iv, 37-41, 81-88, vi, 128-9;
units of, iv, 79-80, ix, 295;
unit equivalents table, vii, 382;
universality of, iv, 13-14;
work and, 37-40, 78-88;
(see also Atomic E., Chemical E., Electrical E., Human E., Molecular
E., Power)

Engines, air and water cooled, v, 160-1;
Clausius's principle, xvi, 135;
heat, efficiency of, iv, 192;
reciprocating and rotary, v, 148;
two-cycle and four-cycle, 157-9;
(see also Gas Engines, Gasoline Engines, Internal Combustion Engines,
Steam Engines, etc.)

Engines of Destruction, v, 359-75

England, Alpine Invasion, xvi, 49;
beet cultivation in, xiii, 216;
"Blackthorn winter," i, 363;
chalk deposits, iii, 266;
climate of, xiv, 345;
coal supply, v, 172;
coast destruction, iii, 56, xiv, 47, 301;
coffee consumption, xiii, 232;
early criminal justice in, xv, 372;
first recorded eclipse, ii, 210;
former connections with Europe, xiv, 271-3, xv, 76;
grass snake of, xii, 217-18;
insular position and results, xiv, 279-81, xv, 137;
iron industry, v, 316;
jute manufacture, xii, 243;
lakes of, xiv, 200;
landscape gardening, xiii, 267, 268;
maritime supremacy, xiv, 262, 280-1, 307-8, 310;
oak-hazel copses, xiii, 369-70;
primitive inhabitants, xv, 83, 92-3;
rainfall and verdure, xiv, 352;
recent restrictions on power vehicles, v, 212-13;
smallpox inoculation in, x, 207;
sugar in, xiii, 215;
surgery made a profession, x, 105;
tea in, xiii, 228-9;
tobacco introduction, 256;
trees in, xiv, 375

English Alphabet, xv, 176

English Channel, first aeroplane flight, i, 43;
historical importance, xiv, 279-80, xv, 137;
impassable to quadrupeds, xiv, 273;
tidal power system, v, 175-6;
tides of, xiv, 294

English Language, changes in, xv, 156-7;
double meanings of words, 158-9;
foreign words in, 161;
imitative words in, 153-4;
origin of various words, 157, 161;
relationships, 160, 162;
spelling and pronunciation, 176-8

English People, characteristics, xiii, 172;
insularity of, xiv, 280

English Sparrow, increase in U. S., xv, 21

Entada Scandens, xiii, 347-8

Enterokinase, x, 326

Entropy, iv, 193, xvi, 135

Environment, adaptation to (see Adaptation to Environment);
change of, to relieve fatigue, x, 247;
changes of, new species from, xv, 24-5;
defined, x, 228;
geographical, influence on civilization, xiv, 30-1, xv, 31, 122-39;
habit and, xi, 249;
health and disease factor, x, 237-44, 249-55, 303;
heredity and, ix, 344, x, 228-30, xvi, 47;
instincts as response to, xi, 49-53;
man creature of, 57-8;
man's conquest of, xv, 25-6;
man's regulation to, x, 249-51;
man the product and molder, of, xi, 33;
mental effects of, x,
354;
mind as response to, xi, 12, 24, 58;
plant response to, xiii, 355-7;
selection of, xi, 257;
will and, 265

Envy, sentiment of, xi, 148

Enzymes, viii, 376, ix, 227, xiii, 83;
in digestive processes, viii, 103, 226, 228, 357, 358, ix, 227, 228,
229-30, 235, 242;
in infants, ix, 346;
in tea, xiii, 230;
in tobacco curing, 257

Eocene Period, animals of, xii, 306, 366;
birds of, xv, 71

Eolithic Period, xv, 103-5

Epic Poetry, development of, xv, 321

Epicurus, atom theory, x, 26

Epicycles, ii, 35-6

Epidemics, Sydenham on, x, 74;
tainted water and, xiv, 140

Epigenesis, xvi, 118

Epileptics, multiplication of, x, 235-6;
primitive ideas of, xv, 350, 353

Epiphytes, xiii, 185, 362-3, 366;
in tropical forests, xiv, 368

Epithelial Cells, x, 201, 202

Epsom Salts, viii, 149

Epyornis, eggs of, xii, 249

Equator, altitude of stratosphere at, i, 20;
bulging at, ii, 69, 71;
magnetic, xiv, 246;
of wind system, xiv, 347;
solar eclipses seen at, ii, 215;
upper air temperatures, i, 20;
weight of bodies at, ii, 69, iv, 75, 101;
winds at, i, 127, xiv, 351

Equatorial Belt, winds and weather of, xiv, 348, 349

Equilibrium of Chemical Reactions, viii, 103-5, 190-1

Equilibrium of Forces, v, 183-4;
science of, iv, 25

Equilibrium Sense, ix, 89-90, 156, x, 126, xi, 64, 126, 127;
in infants, ix, 350

Equinoxes, defined, ii, 70-1;
observed in Egypt, 25, 26, xv, 269-70;
precession of (see Precession of Equinoxes)

Eras, Geological, iii, 19-21, 378

Erasistratus, x, 23-4

Eratosthenes, ii, 10, 30

Erbium, symbol and atomic weight, viii, 383

Erg, energy unit, iv, 80;
table of equivalents, vii, 382

Ericsson, air engine, v, 380;
Monitor, 380;
solar engine, ii, 169;
steam fire engine, v, 378

Erie Canal, importance to New York, xiv, 267-8;
through Mohawk Valley, 194

Erie, Lake, salt in, viii, 139;
water constituents, 40;
water supplies from, v, 260-1

Ermines, xii, 349-50

Eros (asteroid), ii, 191;
distance, 132, 259

Erosion, iii, 28-9, 378;
agents and processes, xiv, 39-79
(see also Glaciers, Ocean Waves, Streams, Wind);
bad lands and canyons due to, iii, 139-40;
base level, 30, 377 (see Base Level);
by ground water, xiv, 141, xvi, 173;
cycles (see Cycles of Erosion);
earth movements and, xiv, 39, 40;
final effect of, 80;
illustration of recent, iii, 64 (Pl. 3);
in deserts, 72;
in Ice Age, 242;
of faulted areas, xiv, 127;
of folded areas, 94-6;
of mountains, iii, 135, 139, 140-1, 188, 190-1, xiv, 233-4;
present relief due to, iii, 32;
rate of, xiv, 41;
unequal operation of, 35

Erosion Surface (see Unconformity)

Errors, fatigue and, xi, 274;
of memory, 215-17;
in space perceptions, 183-90
(see also Mistakes)

Erysipelas, germ of, x, 195;
immunity to, 207;
puerperal fever and, 114

Eskers, iii, 70, 352 (Plate 20), xiv, 59-60

Eskimos, conditions of life, xv, 123-4;
customs concerning dead, 338;
ideas of future life, xv, 333, 335;
kayaks of, 264 (fig.);
language lacking in abstract words, 144;
leadership among, 363;
meat eating by, ix, 284, 309;
polar bear catching by, xv, 224-5;
reindeer uses, xii, 320;
weapons of, xv, 209 (fig.), 210-12

Esophagus, functions and connections, ix, 230, 231;
heartburn in, 232;
operations of, xi, 37-9

Esparto Grass, v, 292

Espy, James P., i, 215, 345

Essential Oils, viii, 251-2, 336, 349

Esters, viii, 221, 245, 248, 376

Estuaries, formation of, iii, 37, xiv, 255, 256

Eta Argus, ii, 324

Eternity, real meaning, xi, 196

Ethane, derivatives, viii, 210

Ether, composition and properties, viii, 216-18, 376;
density of, iv, 113;
explosibility, viii, 62;
refrigeration by, iv, 174;
use as anesthetic, discovery of, x, 123-5, xvi, 185

Ether of Space (see Æther)

Ether Structure, viii, 217, 224

Ethyl, defined, viii, 376;
derivatives, 210

Ethyl Acetate, viii, 221

Etna, Mount, xiv, 100, 225, 316-17;
flashing arcs, i, 194;
water from eruption, iii, 107

Etruscans, vase decorations of, xv, 251

Eucalyptus Tree, xiii, 358;
fertilization of, xii, 266-7;
used in draining swamps, xiv, 379

Euclid, ii, 29, xvi, 81, 89, 95

Eudoxus, ii, 31, 300

Eugenics, x, 235-6, xvi, 157, 158

Euler, scientific work of, ii, 15, xvi, 125

Euphrates River, union with Tigris, xiv, 185

Europe, aeroplane routes, i, 44-5;
after-summers, 362;
Alpine invasions, xvi, 49;
ancient animals, xii, 275, 310, 359;
animals (carnivora), 336, 340, 348, 349, 350, 355, 356;
animals, (herbivora), 307, 317, 318, 329, 330-1;
aristocracies of, xv, 377;
Asiatic invasions, xiv, 74-5, 362, xv, 138-9, xvi, 141;
beet sugar production, xiii, 216;
birds of, xii, 255, 261, 262, 263, 266, 268-9;
Black Death in, x, 163-4;
cave period in, xiv, 148-9;
civilization in northern, 359;
climate of, 346-7, 359;
coast, western, 249;
coffee introduction, xiii, 232;
continental slope, xiv, 287;
cretinism in, x, 350;
Cro-Magnons in, xv, 99, 102, xvi, 50;
dowry system in, xv, 285;
drainage systems, xiv, 190;
earthquake belt, 332;
forests, 375-6, 377-8, 380-1;
former connection with America, 290;
geological history, iii, 180, 198, 216, 235-6;
glacial topography, xiv, 3, 30, 43, 61-2, 200;
gunpowder introduction, xvi, 101;
hail prevention devices, i, 340-3;
Ice Age in, iii, 62, 236-7, 239, 240, xv, 74, 75, 76, 102;
languages of, 161, 162;
map discrepancies, xiv, 10;
mediæval astronomy in, ii, 39-41;
meteorological statistics, i, 203;
monkeys of, xii, 378;
moor fires, i, 56;
mussel-eating in, xii, 65;
Nordic invasion, xvi, 50;
nutmeg introduction, xiii, 261;
paper introduction, v, 290;
paper making, 292;
plains of, xiv, 217;
population increase, xv, 27;
potato in, xiii, 218;
primitive man types found in, xv, 88, 92-102;
rainfall distribution, xiv, 352;
rainfall stations, i, 79;
revival of learning (see Renaissance);
rice in, xiii, 214;
rodents of, xii, 287, 288;
snails of, 69, 70;
snakes of, 218, 220, 231;
snow removal in cities, i, 117;
sugar introduction, xiii, 215;
syphilis in, x, 60;
tea introduced, xiii, 228;
telegraph systems, vii, 108;
tobacco introduced, xiii, 256;
trees of, xiv, 363, 375-6;
vegetables and fruits originating in, xiii, 222-7;
volcanic belts, xiv, 316-17;
weather observations, i, 217-18;
windmills, 37

European Races, classification and history, xvi, 48-50

Europeans, comparative measurements of, xv, 57;
hair of, 38;
northern and southern, color of, 37

European Sleeping Sickness, x, 301-2

Europium, symbol and atomic weight, viii, 383

Eustachian Tube, ix, 101 (fig.), 102, xi, 101;
adenoid effects on, x, 341-2;
deafness from closing of, ix, 103-4;
discovery, xvi, 82

Eutheria, xii, 271, 273-4, 281

Evaporation, body heat regulation by, i, 317, 318, ix, 316, 317;
by trees, xiv, 377-8, 378-9, 379;
(see also Transpiration);
cooling by, iv, 174, viii, 69, ix, 316;
electricity, caused by, vii, 212;
ice made by, v, 349-50;
measurement of, i, 88-9;
of liquids, iv, 167;
of terrestrial waters, xiv, 135;
water table affected by, 136

Evaporimeter (see Aumometers)

Everglades, Florida, draining of, v, 255

Evergreen Trees, deciduous, xiv, 370, 371;
in landscape gardening, xiii, 269, 270, 271 (See also Conifers)

Evesham Experiments, vii, 352

Evil Spirits, savage belief in, xv, 234, 304-5, 336, 339-40, 348, 352

Evolution, animals the main proof of, iii, 259, 260;
Buffon on, xvi, 139-40;
climatic, iii, 174;
Darwinian theory, x, 135, 136, xvi, 149-52;
Greek theories, 78-9, 139;
human, xv, 26-31, xvi, 47;
laws of, xv, 15-25, 381-2;
laws and goal of, xiii, 325-36;
Le Conte on, iii, 164;
social, xv, 29-31, 382, 383-4;
universality of, ii, 366, xv, 29, xvi, 152;
Wolff's theory, xvi, 118

Exaggeration of Parts, iii, 277

Excavating, air pressures in, v, 120;
through quicksands, 115-18, 123;
under river-beds, 121-4;
with water jets, 88

Excavating Machinery, v, 252-9;
for swampy ground, 216

Excitement, blood changes in, ix, 293, xi, 137, 138;
insomnia from, ix, 219;
pain and, xi, 119;
recovery period, 21

Exclusive Inheritance, x, 230-1

Exercise, effects, needs and rules, x, 303-6;
effects on breathing, ix, 256, 258;
effects on heart rate, 168-9, 207, 208-9, 261-2, x, 334;
effect on lymphatics, ix, 223;
effects on sweat glands, 169, 315-16;
for constipation, 251, x, 317;
heat produced by,
270, 306;
obesity and, 273-4, 275;
oxygen consumption in, ix, 261;
psychological importance, xi, 339, 371-2;
pulse rate after, x, 334;
tuberculosis preventative, 292;
violent, albuminuria from, 345

Exfoliation, iii, 24, 378

Exhaust, of engines, v, 164-5

Exhaust Fans, vii, 86

Exhaustion, kinetic theory, xi, 59-60;
mental and physical, 135-6;
nervous system in, 274;
pain in, 119;
unlike sleep, 286

Exoskeleton, xii, 127

Expansion, by heat, iv, 134-5, 138, 140, 145, 151, v, 71, viii, 25, 107;
coefficient of, iv, 145;
cooling by, i, 30, 90, iv, 188, 191-2, vii, 323, viii, 68;
of fused quartz, vii, 311-12;
of water and other substances on solidifying, iv, 149-51, viii, 38

Experience, ability to profit by, ix, 139-40, 152-3;
accumulation and results, xi, 33;
contradictions of, 11;
learning and, viii, 269;
learning by, in man and animals, xv, 66;
psychology science of, xi, 10-11;
sensations as, 68;
subconscious storing of, 47;
Sylvius's test of truth, x, 69

Explanations, slower than events, xi, 210

Exploration Drilling, v, 262-5

Exploratory Laparotomy, x, 147

Explosions, boiler (see Boiler Explosions);
cause of detonations, vii, 211;
chemical and physical processes, viii, 61-3;
dust, i, 63;
gunpowder, viii, 62, 145;
hydrogen in air, 33, 36, 62;
speed of sound in, i, 187

Explosives, viii, 63, 260-2;
detonation, 262;
history of development, xvi, 163;
nitrogen compounds in, viii, 66, 71-2, 74, 75, 237, 253, xiv, 66;
nitrogen waste in, viii, 345-6;
sulphuric acid in, 80;
weather making by, i, 335-9

Exposure (outcrop), iii, 381

Extemporaneous Speeches, xi, 245

Extension, perception of, xi, 166, 171-2, 183-9

Extensor Muscles, ix, 76-7, xi, 54, 166

Exteroceptive Senses, xi, 63

Extrusive Rocks, xiv, 105

Eye-and-ear Method (astronomy), xi, 155

Eyeglasses, benefits of, iv, 51
(see also Glasses)

Eye-mindedness, xi, 222

Eye of the Storm, i, 136, 372