Tamia-caspi, i, 352

Tampers, pneumatic, v, 135

Tampico, harbor of, xiv, 266

Tan, skin, vii, 249, 253

Tanagers, xii, 245, 269

Tanganyika, Lake, size, xiv, 204

"Tanks", in World War, v, 218, 384

Tannic Acid, in tea, xiii, 231

Tannin, uses of, viii, 257, 259

Tanning, of hides, viii, 257;

in ancient Egypt, xvi, 73

Tantalum, symbol and atomic weight, viii, 383

Tapegrass, fertilization, xiii, 150-1

Tapeworm, x, 200, xii, 45;

food of, ix, 18;

motions of, 73

Tapioca, source, viii, 243

Tapirs, xii, 304, 306

Taproots, xiii, 16, 17, 18

Tar, constituents of, viii, 333;

production and uses, 253

Tarantella (dance), xii, 93

Tarantulas, xii, 93

Tarnishing, of metals, viii, 13, 77, 100

Tarpons, xii, 154

Tartar Astronomers, ii, 39

Tartar, on teeth, x, 315-16

Tartaric Acid, viii, 136, 222-3, 336;

asymmetric atoms of, 309-10;

Pasteur's study of, x, 137

Tasmania, aborigines, iii, 303, 304;

animals of, xii, 277-8;

continental island, xiv, 276;

leafless yew-tree, xiii, 30

Tasmanians, hair of, xv, 38;

in black race, 37

Taste (sense), ix, 94-5, 96, xi, 69-77;

in infants, ix, 350-1;

mingled associations with, xi, 64, 127;

phonisms of, 222

Taste Buds, ix, 94, 95;

related to end-buds of fishes, xii, 137

Tastes, agreeable, digestion aided by, ix, 98, 240, x, 320

Tattooing, xv, 257 (fig.), 258-9

Taughannock Falls, iii, 50

Taylor, Bertha Fanning, xiii, 4

Taylor, Fred W., v, 54-5, 383

Taylor, Dr. Griffith, i, 324

Taylor, Prof. Norman, author BOTANY, Vol. xiii

Tea, history and production, xiii, 227-31;

over-boiling, 231;

polyuria from drinking of, x, 344;

wakefulness from, ix, 219

Teakettles, heating of, iv, 182-3

Tea Plant, xiii, 228, 229-30;

ancestral home, 221

Teak-wood, source, xiv, 383

Tear Gases, viii, 263

Tear Glands, blood supply of, ix, 197;

control of, 162, 163

Tears, cause, xi, 23;

taste sensations and, 76

Technical Terms, glossary of, iv, 381-4

Tectonic Topography, xiv, 94

Tedium, xi, 194-5

Teeth, ancient birds with, iii, 296, 297, xii, 241-3;

care of, ix, 228, x, 313-16;

decay of, cause and results, 312-13, 314;

decay from emotional strain, xi, 142;

defective, mental impairment by, 373;

diet and, x, 265, 314-15;

diseased, fatigue from, xi, 279;

electric treatment, vii, 237;

enamel of, ix, 13;

grinding of grains by, xv, 237-8;

infections from, x, 202, 218, 222, 225-6;

killing of nerves of, ix, 187, 188;

loss of, results on jaws, 57;

malnutrition from bad, 228;

modified scales, xii, 134;

mutilations of, by savages, xv, 260;

of carnivores, xii, 332-3, 389;

of manlike apes, iii, 303;

of Neanderthal man, xv, 98 (fig.);

of rodents, xii, 286;

of Tertiary mammals, iii, 298, 300;

poisons from decaying, ix, 269-70;

pus pockets at roots of, 187, 188;

replacing of sound, x, 56;

temporary and permanent, 313-14;

ulcerated, ix, 56;

X-ray examinations, x, 373, vii, 254

Teguexins, xii, 208

Tejus Lizards, xii, 208

Telautograph, vi, 98

Teleosts, iii, 285, xii, 142, 151-66;

eggs of, 141

Teledu, stinking, xii, 348

Telegraph, Telegraph System, iv, 292-4, vii, 108-18, 376;

cells used, vi, 127, 140;

etymology of word, vii, 91;

invention, 108, vi, 24, xvi, 188;

protection against lightning, vii, 49-50;

sounders, 375;

submarine, vi, 24

Telegraph Codes, vii, 108-9

Telegraph Plant, xiii, 114

Telegraph Plateau, xiv, 288

Telegraph Poles, in desert regions, iii, 72-3

Telegraph Wires, humming of, i, 194-5

Telephone Exchange, brain compared to, xi, 15-16;

central nervous system compared to, ix, 129

Telephone, Telephone System, iv, 305-6, vii, 91-107, 376;

automatic, vi, 87, vii, 92-3, 106-7;

cells used, vi, 138, 142;

condensers in, 285, 304;

invention, v, 381, vii, 92, xvi, 188;

magneto-generators, vi, 215;

number in New York, vii, 75;

protections against lightning, 50;

receiver, electromagnet of, vi, 99;

simultaneous messages, vii, 118-19;

vacuum tubes in, 280;

vibration rates of, ix, 101;

wire used, vii, 314

Telephony, prominent names in, vi, 26

Telescopes, ii, 93-110, iv, 345-6;

comet-seekers, ii, 274;

first used by Galileo, 54;

first eclipse seen by, 210;

Galileo's, xvi, 103;

lens improvements, 125;

limitations due to atmosphere, ii, 140, 201-2;

modern, 18, 143

(see also Bruce, Hooker, Leviathan, Yerkes Telescopes);

use in astronomical photography, iv, 372-3

Telluride Ores, iii, 366

Tellurium, classification place, viii, 182, 183;

symbol and atomic weight, 383

Temperament, classes of, xi, 153-9

Temperate Forests, xiii, 366-73, xiv, 366, 370-1;

timber supply from, 382-3

Temperate Zone, civilization in, xv, 122, 123, 127, 383, xiv, 344, 357-9;

most favorable to man, xi, 51;

weather, how determined, xiv, 349-50;

winds, i, 127-8, 135, 137, xiv, 345-6, 349

Temperature, absolute, viii (see Absolute Scale);

altitude and, i, 19, 20, 208, xiv, 364-5;

barometric pressure and, iv, 122-3, 124, 125;

body (see Body);

climate classification by, i, 208;

colors in relation to, iv, 361;

critical (see Critical Temperature);

daily range, xiv, 247-8;

dependent on atmospheric constituents, i, 14-15, 16, 58-9, iii, 248;

determining factors, i, 208, xiv, 344-7;

electrical conductance affected by, iv, 301;

equalization by water, viii, 37, 38;

gas pressure and, iv, 139-42, viii, 107;

heat and, iv, 139-40, 144-5, 153-4;

high and low attained, v, 345, 348;

highest atmospheric, i, 209;

human control of, 332-3;

human efficiency and, i, 323-4;

human feelings of, 317-18, 320-1, ix, 93-4, 319-21, xi, 112-14;

humidity and, i, 76, 77, xiv, 352-4;

infant's adjustment to, ix, 352;

latitude and, xiv, 344-5;

lowest atmospheric, i, 209-10;

maximum and minimum, i, 75-6;

mean, 203-4;

measurement of (see Thermometers);

measuring of high, iv, 137-8, vi, 62-3;

metabolism affected by, ix, 37, 78-9;

musical instruments affected by, iv, 231-2;

observations and records, i, 203-5;

of deep sea, xii, 21-2;

of electric arc, iv, 312;

of electric furnace, vii, 302, xvi, 189;

of liquid air, i, 31, viii, 68;

of meteors, ii, 285, 290;

of oxyacetylene blowpipe, i, 33;

of stratosphere in different latitudes, 20;

of sun, ii, 169, iv, 194;

optimal, xi, 51;

physical state and, viii, 303-5;

plant distribution determined by, xiv, 364-71, 374-7;

plant societies in relation to, xiii, 357, 381;

range of, on earth, ii, 243-4;

range possible for life, i, 32, ii, 243-4, 245, 249, v, 348-9, x,

250-1;

rise of, to what due, iv, 144;

scientific meaning of, 139-40, 144;

seeking of favorable, xi, 51-2;

sensations of, ix, 93-4, 314, xi, 112-14;

sensible, i, 318;

sound speed and, i, 186-7, iv, 198-9;

subterranean layers of, xiv, 12-15;

susceptibility to change of, x, 240;

sun-spot effects, i, 16;

variability, i, 204-5;

variations by night and day, iv, 134, 183;

variations, effect on timepieces, v, 71-2, 73;

variations, human effects, x, 238-9;

variations and rock weathering, iii, 23-4, 72, xiv, 41, 62, 74, 75,

77-9, 233;

ventilation factor, viii, 331, 332;

volcanic dust effects, i, 58-9;

winds in relation to, 124, 126-7, 131, 293, xiv, 345-7

(see also Heat)

Temperature Charts, i, 206

Temperature Inversion, i, 375

Tempered Scale (music), 4, 208-9

Ten Commandments, xv, 368

Tender Emotion, xi, 146, 147, 149

Tendon of Achilles, ix, 76

Tendons, ix, 59, 79;

early surgery of, x, 79, 96;

sensations of, xi, 124, 125

Tendrils, xiii, 28;

movements of, 111-12;

on leaves, 38

Teneriffe, Smyth's experiment on, ii, 141;

volcanic nature, xiv, 277, 316

Tennessee, non-glacial topography of, xiv, 56;

underground streams of, 149

Tennessee River, former course, xiv, 186

Tennis, "cutting" of balls in, iv, 67, 68-9

Tennyson, in Holmes' "goodly company," x, 134;

quoted, i, 136, 183, iii, 11, xi, 33

Tension Spring, air as, v, 136-7

Tents, Indian, xv, 266

Teratoma, x, 120

Terbium, symbol and atomic weight, viii, 383

Term Hours, i, 203, 383

Terminal, of moon, ii, 28

Terminal Moraines, iii, 67;

lakes formed by, xiv, 202;

of great Ice Sheet, iii, 67-8, xiv, 59, 200, xv, 74-6

Terminal Voltages, vi, 186, 188, 189

Terminals (see Railroad Terminals)

Terminator (astronomical), ii, 194, 202

Termites, xii, 110, 125

Terns, xii, 264

Terpenes, viii, 240, 251-2

Terra Firma, iii, 76

Terraces, defined, iii, 383;

of California, 224

Terrapins, xii, 189-90

Terrestrial Refraction, i, 171, 380

Terror, exhaustion from, xi, 135-6;

expression and origin, 131-3

Tertiary Period, iii, 20, 221-36, 383;

appearance of man in, xv, 72;

development of mammals in, xii, 271-2;

divisions and species surviving, xv, 71;

plants and animal life, iii, 257, 279, 297, 298-9, 300, 301-2, 303,

xii, 104, 154, 243, 283, 366;

remains of man in, v, 11

Tesla, Nicola, vi, 26

Testudinidae, xii, 188

Tetanus, negro susceptibility to, xv, 51

(see Lockjaw)

Teptonic Races, in Nordic group, xvi, 48

Texas, chalk deposits, iii, 216-18;

chapparal of, xiv, 379;

coasts of, iii, 57, xiv, 251, 262, 263;

cotton, xiii, 237;

dust whirlwinds, i, 60;

mercury production, iii, 370;

monsoons, i, 131;

oil wells, helium from, iv, 108;

peccary of, xii, 311;

stock-raising system, xiv, 383

Texas Fever, xii, 98

Textile Machinery, v, 268-83, 376-7;

induction motors in, xi, 256;

of ancient Egypt, xvi, 72-3

Textiles, chemistry of, viii, 254-8;

Egyptian, xvi, 72-3;

fireproofing of, viii;

starch in, 243

Thackeray, W. M., brain weight, xv, 39

Thales, discovery of magnetism, vi, 11;

eclipse predictions, ii, 9, 27, 209-10;

scientific teachings, xvi, 76-7, 77

Thallium, symbol and atomic weight, viii, 383

Thallophytes, iii, 250, 251, 252, 256

Thallus, of ferns, xiii, 156-7;

none in mosses, 163

Thames River, former tributary of Rhine, xv, 76;

tidal basin, v, 176;

true mouth of, xiv, 270

Theatres, color induction in, xi, 95;

use of ozone in, vii, 353-4;

wiring, 57

Thebes, Egyptian, xvi, 64, 65, 67, 70;

papyri discovered at, x, 12

Thenard, chemical work, xvi, 162

Theobromin, polyuria induced by, x, 344

Theology, Creek, Roman, medieval, xvi, 99-100, 115

Theophrastus, zoölogical work, xvi, 126

Therapy, Therapeutics, x, 379-84;

aeronautics in, i, 51;

ancient systems of, x, 12, 13, 21-2, 26, 380;

Brunonian system, 89-90;

climatological, i, 331, x, 383;

drug, 21-2, 380-1;

electricity in (see Electro-therapeutics);

hypnosis in, xi, 317;

Locke and Holmes on, x, 74-5;

modern, 380-4;

nihilism doctrine in, 113;

open-air, 240-1, 291;

Rowntree's categories of, 380;

Stahl's system, 85;

Sydenham's glossary of, 74;

X-rays in, vii, 251, 252-3, 255-6

Thermal Belts, i, 259, 383

Thermal Couples, vi, 62-3, 72;

electron theory, vi, 123-5;

power tables, vii, 383;

source of energy, vi, 129

Thermal Springs, xiv, 143-5

(see also Hot Springs)

Thermal Unit, v, 350-1

Thermionic Valve, vi, 125

Thermodynamics, iv, 384;

great laws of, 189-94

Thermo-electricity, vii, 376

Thermo-electric Powers, vii, 383

Thermograph, i, 76, 77, 383

Thermo-junction, i, 318

(see Thermal Couples)

Thermometers, i, 72-6, 383, iv, 135-8, 145;

as comfort measures, i, 318;

comparison of scales, iv, 137 (fig.), xiii, 27, 384;

development, i, 68-9;

drugstore, 266;

Galileo's, x, 71;

metallic, iv, 146-7

Thermometer Screen, i, 375, 383

Thermos Bottle, construction and use, iv, 184-5;

invention, vii, 323;

principle, i, 31, viii, 68

Thermoscope, i, 69

Thermostat, iv, 148-9, 384, vii, 87

Thermostatic Regulators, vii, 148

Thermotaxis, xi, 51-2, 61

Theromorpha, xii, 184-5;

mammals developed from, 271

Thibet (see Tibet)

Thigh, bone of, ix, 68, 70 (fig.)

Thimbleberry, xiii, 199 (fig.)

Thinking, law and process of, xi, 201

(see also Thought)

Thinness, x, 277

Third Dimension, perception of, xi, 173-83

Third Rail System, vii, 187, 189, 197-8, 199 (fig.)

Thirst, exercise effects, x, 303-4;

sensation of, ix, 87, 88-9, xi, 66-7;

sense of, in infants, ix, 350

Thomas, Holt, on airships, i, 42

Thomas of Sarzona, x, 44

"Thomas W. Lawson," schooner, v, 188-9

Thompson, Benjamin (see Rumford)

Thompson, S. P., vi, 26

Thompson, William (see Kelvin)

Thomson, Elihu, vi, 26

Thomson, J. J., cathode ray studies, xvi, 193;

electron theory of, iv, 55, vi, 26;

experiments on gas cooling, i, 30

Thomson Water Meter, v, 87

Thorax, diagnosis of diseases of, x, 98-9, 109;

of insects, xii, 99, 102

Thoreau, on Indian summer, i, 362

Thorium, in soil and air, i, 143;

radioactivity, viii, 184, 186;

symbol and atomic weight, 383

Thorn Tree of Natal, xiii, 375

Thorpe, John, ring frame, v, 378

Thothmes, war chariot of, xv, 242

Thought, brain processes in, ix, 147-53, xi, 15;

cerebrum seat of, ix, 167;

gray matter and, xv, 63;

habits of, xi, 198, 203-4, 247;

language and, xv, 143-45, 146;

law and process of, xi, 201;

need of changes of, ix, 138;

nervous mechanism, xi, 19-20;

physical essentials and costs, 25;

speed of, 13

(see also Reaction Types);

Stoic definition, 228;

stream of, 193;

similarity in laws of, xvi, 42-3

"Three Fates", painting, xi, 192

Three-Horned Beast, iii, 292

Three-phase, meaning, vi, 207

Threes, multiplies in plants, xiii, 176, 178

Threshing Machines, v, 248-9

Threshold of Sensation, xi, 71;

of distance discrimination, 184, 185;

in various senses, 80, 104-5, 111

Throat, as infection focus, x, 219, 224;

connections with ear, ix, 101, 102 (fig.);

drying of, in thirst, iv, 88;

in speech production, ix, 83

Thrombosis, x, 336

Thrush, disease, x, 196

Thrushes, xii, 269

Thrust Bearings in Niagara Plant, vi, 374-5

Thrust Faults, iii, 87, 88 (fig.);

examples, 90-2, 188, 219

Thugs, jaws of, xv, 43

Thulium, symbol and atomic weight, viii, 383

Thulis, astronomer, ii, 275

Thumb, flexibility of human, ix, 67-8;

of apes and men, xv, 58-60

Thunder, i, 383;

at sea, 193;

cause of sounds, 192-3;

distances heard, 188-9;

explanation, vii, 210-11;

general awe of, 201-2;

large raindrops and, 215-17;

reverberations of, iv, 238;

speed of sound, i, 187

Thunderclouds, i, 102, 296;

formation, 93

Thunderhead, i, 139 (fig.), vii, 217

Thunderstorms, i, 138-9, 383;

astraphobia, 330;

classes and causes, vii, 217-18;

dangers and protection, i, 155-7;

hail in, 106, 120, 373-4;

lightning flashes, 149-52;

potential differences in, vii, 352;

St. Elmo's Fire in, i, 157;

strays and, 163;

vertical currents in, 293

Thunderstorm Recorders, i, 163, 383

Thuringian Forest, xiv, 238

Thylacine, xii, 277-8

Thyme, flowers, xiii, 205;

origin, 265

Thymol, viii, 238, 333

Thyro-globulin, x, 351

Thyroid Gland, x, 347, 348;

disorders and treatment, ix, 303-4, xi, 60-1;

functions and disorders of, x, 348-52;

inflammation of, and rheumatism, 224;

operations on, 148;

secretion used as drug, 382

Tiamat, or Chaos, xvi, 77

Tian Sham, xiv, 232

Tiber River, delta of, xiv, 263

Tibet, bears of, xii, 337, 338, xiv, 205, 211;

marine deposits, iii, 235;

plateau of, xiv, 97, 222, 232;

polyandry in, xv, 286;

rainfall, i, 111, xiv, 355;

wild ass of, xii, 308;

yak of, 330

Tibetans, in yellow race, xv, 37

Tickle, Tickling, sensation of, ix, 92-3;

sense of, xi, 109, 114;

laughter from, 355

Ticks, xii, 98

Tickseed, seed dispersal, xiii, 58, 343

Tick Trefoil, xiii, 58

Tidal Estuaries, formation of, xiv, 164, 255

Tidal Friction Theory, ii, 375-7

Tidal Power, v, 174-7

Tidal Races, xiv, 294

Tidal Waves, from earthquakes, xiv, 337;

from Krakatoa eruption, iii, 101, xiv, 324

Tide-predicting Machines, v, 327

Tides, xiv, 291-5;

Bacon's lunar theory, xvi, 101;

cause, ii, 70, v, 177, xiv, 32, 291;

erosive work of, 44-5;

importance to shipping, 295;

local ranges and peculiarities, 293-4;

neap and spring, ii, 70;

daily occurrence, xiv, 291-2, xiv, 292;

power utilized, v, 174-7;

"races", 294;

variations in rise and fall, 292-3

Tides, Plastic, ii, 375

Tide Water, sewage disposal in, viii, 325

Tied Images, xi, 221

Tierra del Fuego, climate and forests of, xiv, 371

Tiger, saber tooth, in Europe, xv, 76;

strength of, 18

Tigers, xii, 357-60;

apes and, 362;

Tiger Triton, 172-3

Tigris River, civilization on, xv, 123;

mapping of flood areas, i, 47;

rafts used on, xv, 264;

union with Euphrates, xiv, 185

Tilefish, xii, 164

Till, glacial, iii, 67, xiv, 59, 61

Tillamook County, Oregon, rainfall, i, 112

Tilling Machines, v, 244

Timber, source of, xiv, 382-3

Timber Line, xiv, 233

Timber Wolf, xii, 340

Timbre, of sound, xi, 104

Timby, Theodore R., v, 380

Time, absolute and relative, ii, 80, iv, 16-18;

coordinate for determining events, 16;

geological (see Geological Ages);

measuring of, v, 57-74;

memory perception, xi, 208;

Newton on absolute and relative, iv, 15;

origin of word, xi, 192;

perceptions of, 192-6;

primary concept, iv, 14, 15;

relative, Newton on, 15;

relativity doctrine, xvi, 196-8;

units of, iv, 15-16, 45, 46, 70

Timepieces, Chaldean, xvi, 58;

civilization and, v, 57;

historical development, 58-65

Time-rate, iv, 383

Timocharis, ii, 28-9, 31

Tin, viii, 161;

alloys with lead, melting point, iv, 161-2;

atomic weight and symbol, viii, 383;

affinity strength, 128;

extraction from ores, 271;

fusibility, 384;

in heavy metal group, 126-7, 154;

melting point and requirements, iv, 162;

positiveness, vi, 59;

production and uses, iii, 368-9;

specific gravity, viii, 384;

tests for, 287, 288;

uses, viii, 161

Tin Plating, viii, 273

Tinstone, viii, 161

Tint, of colors, xi, 90

Tips, of plants, xiii, 111, 114

Tire Pumps, heat of, v, 351

Tires, iron, on wagon wheels, iv, 4, 134-5;

pneumatic and other, v, 133-4

Tissue Fluids, ix, 50;

abundance in connective tissues, 59;

constituents, 173-81, 189-90;

oxygen supply, 253, 254, 260;

renewal and supply system, 51 (fig.), 191, 193-5;

waste products removal, 221-2, 262

Tissues, amino acids in, ix, 284, x, 204, 277-8;

blood acidity neutralized by, 280, 281;

carbon dioxide, production and removal, ix, 262, 264;

chemical composition, viii, 298, 348, 354, 355;

colloidal condition, viii, 356;

connective (see Connective Tissues);

diseased, composition and X-ray treatment, vii, 253, 255-6;

electricity effects, 247;

energy sources, ix, 289, 290, 291, 297;

growth of various kinds, 47-8, 286-7;

infections of, x, 204;

"irritability" theory of, 86;

oxygen needs and supply, ix, 253, 260, 261-2, x, 331, 338;

protection against germs, 201;

protein needs, viii, 359, ix, 278-84, 287-9, x, 204, 277-8;

resistance to germs, 197-8;

spaces for fluid, ix, 50;

wastage, normal, 281-3;

wastage in starvation, 297-8;

waste removal, 271;

water in, viii, 39

(see also Body Cells, Protoplasm)

Titan, moon of Saturn, ii, 249-50

"Titanic," loss of, xi, 332

Titanium, symbol and atomic weight, viii, 383

Titchener, Prof. on imagination, xi, 225;

on skin, 114;

on reaction types, 155

Titicaca, Lake, xiv, 205

Tivoli, Italy, travertine deposits, xiv, 146;

waters of, 147

Tjemoro Tree, xiii, 15

TNT (see Trinitrotoluol)

Toads, xii, 169, 174-7;

evolution of, 167;

rains of, 177

Toadstools, xiii, 164

Toasts, origin of, xv, 363

Tobacco, xiii, 256-9;

American origin, 221;

xiv, 382;

historical importance, xiii, 208;

hyperacidity of stomach caused by, x, 322;

ripened by bacteria, 194

Tobacco Leaf, X-ray sterilization, vii, 257

Todd, Prof. David, author ASTRONOMY TODAY, Vol. ii.

Toddy, flowering of, xiii, 53

Toes, bones of, ix, 69;

rising on, muscle used, 76;

of infants, xv, 61;

use of, by apes and men, 60, 61

Toilet Soap, viii, 142

Toledan Tables, ii, 38, 39

Toledo, blades of, v, 315;

conquest of, effects, x, 37

Toluene, derivatives, viii, 238-9;

from coal tar, 253

Toluidine, viii, 237

Toluol, viii, 235

Tom, Mount, iii, 212, xiv, 111

Tomahawks, xv, 208

Tomatoes, adventitious roots, xiii, 19-20;

berries, 54;

calories in, ix, 299;

food value, viii, 365, ix, 30;

origin, xiii, 221, 224, xiv, 382;

splitting of, xiii, 94

Tomato Tree, origin, xiii, 227

Tomboro, dust from eruption, i, 59, 360

Tommasi, Crudeli, x, 155

Ton, unit of weight, iv, 283-4

Tonal Fusion, xi, 106

Tones, musical, iv, 207, xi, 105-6;

number in Indian scale, xv, 314;

pitch and intervals, ix, 99-100;

qualities of, xi, 104, 105;

simple and compound, iv, 213-17;

vibration rates, iv, 204

Tongue, functions in voice production, ix, 83;

muscles of, 77, 83;

nerve connections, xi, 76;

of chameleons, xii, 209;

of serpents, 211-12;

of toads and frogs, 174;

papillæ, xi, 70, 71;

response to taste, 62;

taste buds of, ix, 94, 95;

touch organs of, 92

Tonopah District, Nevada, xiv, 126 (fig.)

Tonsilitis, rheumatism and, x, 223

Tonsils, infections of, ix, 187, 188, 224;

infections through, x, 198, 202, 219, 220, 221, 223-4, 225;

lymph nodes, ix, 224;

removal of, 224

Tool-making Animals, v, 9-19

Tools, adjustment to workmen, xi, 362;

antiquity of hand, v, 42;

early use of, iv, 24;

historical development, v, 12-16;

machine, 42-56;

of ancient Egypt, xvi, 67;

pneumatic, i, 27-8, iv, 129;

resemblance to hand, xi, 44-5;

stone, evolution of, xv, 102-10;

use by man and animals, v, 9-11, ix, 67-8

Tool Steel, v, 55

Toothache, hypnotic treatment, xi, 315

Top Shells (Trochus), xii, 71-2

Topaz, iii, 340;

oriental, 327

Topography, changes in, xiv, 29-30;

changes, how effected, 33-79;

fault and joint effects, 114-33;

forms determined by rocks, 80-113, 125-6;

importance in war, 92-3;

of old and new areas, iii, 33-5, 36-7, xiv, 30, 47-9;

winds affected by, i, 294, 296-7

(see also Land Surfaces, Relief Features)

Tops, as gyroscopes, v, 339

Tornadoes, i, 137-8, 383;

cores, 299;

devices to dispel, 335-6;

electrification by, vii, 212-13;

lifting power, i, 356;

miscalled cyclones, xiv, 349

Tornado Insurance, i, 269

Torpedo Fish, vi, 16, xii, 149-50

Torpedoes, from aeroplanes, v, 375;

submarine, 340, 373-4

Torque, defined, iv, 384;

of motors, 309, vi, 224-7, 232, 234;

in induction motors, 24 5, 247-8

Torricelli, barometer invention, i, 68, iv, 29-30, 114, 121 (fig.), xvi,

109, 177;

scientific work, 104, 109-10, 111

Torsion Balance, invention, vi, 17-18

Torsion Pendulum, v, 74

Tortoises, xii, 182, 185-94

Tortoise Shell, xii, 185-6;

commercial source, 193

Totalizers, i, 118, 383

Touch (sense), ix, 91-2, 314, xi, 109-11, 114-15;

arrival platform for, ix, 146;

development of, xi, 43;

in fishes, xii, 137;

in infants, ix, 349;

in men and apes, xv, 60;

quality differences, to what due, xi, 164-5;

space perception by, 163, 164-6, 184

Touch Blends, xi, 127-8

Touch-me-nots, xiii, 56

Toul-Verdun Line, France, xiv, 90-1

Tourmaline, iii, 340;

light polarization by, iv, 354

Tours, cave dwellings near, xv, 266

Toxins, x, 196, 197, 296, 299

Trachea (windpipe), as infection center, x, 220

Tracheata, xii, 81

Trachoma, racial susceptibility to, xv, 51

Traction, of locomotives, v, 207;

Electric (see Electric Traction)

Tractors, motor, v, 214, 215-18, 243;

of airplanes, iv, 34

Trade Marks, psychology of, xi, 348

Trade Winds, i, 127, 383, xiv, 348-9;

Columbus and the, i, 128-9;

deflection by earth's rotation, xiv, 32, 348;

dryness of, 355-6;

in Mediterranean lands, 358;

"pulse of atmosphere," i, 218;

salinity of sea affected by, xiv, 296;

variations and depth, i, 130

Traditions, crowd psychology in, xi, 333

Trailing Arbutus, xiii, 202, 351

Training, continuity of, xi, 257

Train Sickness, cause, xi, 127

Traits, hereditary, ix, 328-9

(see also Characteristics)

Trances, Hindoo belief regarding, ix, 11-12, 17, 266-7;

primitive conception of, xv, 328

Transformation of Energy, vi, 128-9;

by muscle cells, ix, 74;

by plants, 27;

in Wilberforce Spring, iv, 85

Transformers, Current, vii, 44-5

Transformers (Potential), vi, 159-60, 306-29;

distinguished from current, vii, 44-5;

distribution units, 25-6;

efficiency, vi, 317, 317-18, vii, 367;

importance of understanding, vi, 9;

in electro-therapeutics, vii, 245-6;

in power plants, vi, 364, 376-7;

in radio generation, vii, 266;

in traction systems, 199;

voltage possible, 9-10

Transfusion of Blood, x, 337-8

Transits, defined, ii, 189;

eye-and-ear observations, xi, 155-6

Translation, energy of, iv, 83-5;

motion of, 85-6

Translations, inadequacy of, xv, 146

Translucent Substances, iv, 324

Transmigration of Souls, xv, 333-4;

morality and, 356-7

Transmission Gears, hydraulic, v, 105-6

Transmitter, telephone, vii, 93-4, 96

Transmutation of Elements, viii, 188-9

Trans-Neptunian Planet, ii, 270-2

Transparency, of glass, viii, 305

Transparent Substances, iv, 324

Transpiration (plants), xiii, 103, 104, 113, 374, 378, 379, xiv, 377-8,

378-9, 379

Transportation, aerial, i, 39, 41-3, 44-5;

civilization and, v, 18;

evolution of, 17-18, xv, 13, 241-3;

friction in, v, 203, 204-6;

meteorology in, i, 267-8;

motor trucks, v, 214;

river, xiv, 191;

wheels, v;

legs, v, 214-15

Transportation Problem (U. S.), vii, 194-5

Transvaal, climate conditions, xiv, 224;

gold production, iii, 365;

law against rain-making, i, 336

Transverse Rivers, xiv, 154;

in Appalachians, 167, 168-9

Trapdoor Spiders, xii, 97

Traps, animal, xv, 224 (fig.), 225-7;

avoidance of, xv, 66

Trauma, x, 255

Travel, educational advantages, vi, 330

Traveled Soils, xiv, 69-75

Traveler's Tree, xiii, 106, 112 (illus.), 189

Travertine, iii, 325, xiv, 146

Treadmills, xv, 239-40

Tree Corals, xii, 43

Tree Frogs, xii, 176, 177-9;

voice of, 170

Tree of Heaven, xiii, 200

Tree Ferns, xiii, 65

Tree Snakes, xii, 221

Trees, ancient, iii, 252, 253-4, 254, 255, 256-7, xiii, 309-10;

Big (see Big Trees);

branching of, xiii, 85-6;

carbon dioxide used by, i, 10;

cone-bearing, xiii, 174 (see Conifers);

danger in thunderstorms, i, 155;

deciduous, xiii, 175;

distribution determined by Glacial Epoch, xiv, 375-7;

felling of, by Indians, xv, 262;

fog drip, i, 351;

hardiness of, xiv, 364;

landscaping, xiii, 269-72;

leaving in forests, xiii, 86-7;

marsh-draining by, xiv, 379;

moisture required by, 377-9;

northern limit of, xiv, 371, 374-5;

older than herbs, xiii, 319;

paper from fibers, v, 290, 292-5;

prairies and, xiii, 374, 375, 376;

rainfall and cold in relation to, 373;

rate of increase by seeding, xv, 19;

rime on, i, 121-2;

rings, xiii, 24-5, 26;

rings, climate changes seen in, i, 199-200, xiv, 362;

rise of water in, xiii, 94;

roots, 16-17, 19;

roots, power of, iii, 24;

shedding of leaves in dry seasons, xiv, 369;

species in America and Europe, 375;

strangled by vines, xiii, 21-2;

stunted, 367;

tallest, 94;

trunks, structure, 23-6;

United States, xiv, 372-4

Trembling, in fear, xi, 132, 133

Tremolite, iii, 321

Trench-digging, competitive test, xi, 363

Trench Fever, x, 202

Trenches, ocean, xiv, 286, 288, 289

Trenching Machines, v, 253, 254-5

Trentino, xiv, 244, 245

Trenton Falls Gorge, iii, 50, 243

Trenton Limestone, iii, 185-6

Trepangs, xii, 50

Trepanning, Hippocrates, methods, xvi, 96

Trephine Operations, x, 27, 79

Trevithic, Richard, v, 207-8, 212, 377

Trial Marriages, xv, 290

Triangles, center of gravity in, iv, 101

Triassic Period, iii, 20, 208-13, 383;

animal life of, 271 (fig.), 285, 291;

appearance of mammals in, xii, 271;

insects of, 104

Tribes, formation of, xv, 363;

primitive morality limited to, 374

Tribes, plant, xiii, 171

Tributary Streams and Valleys, xiv, 56-7

Triceratops, iii, 292

Trichina, cause of, xv, 49;

parasite of, x, 199, xii, 45

Trieste, Gulf of, springs along, xiv, 150

Trifid Nebula, ii, 355, 364, 365

Trigonometry, history of development, xvi, 54, 62, 92, 101

Trilobites, iii, 260, 276-8

Trinidad Head Lighthouse, storm waves at, xiv, 300

Tri-nitro-phenol, viii, 262

Trinitrotoluene, (T. N. T.) viii, 236, 237, 261-2

Trinitrotoluol, viii, 63;

potential energy in, iv, 82

Trinil Man, xv, 89;

brain of, 96

Triphenyl Methane, viii, 240

Triple Register, i, 88

Tripoli, intersection of eclipse paths in, ii, 216

Tripolite, iii, 335

Trogons, Mexican, xii, 267

Trojan War, hashish at time of, xiii, 239

Trolley Cars, uses and disadvantages, i, 41

(see Electric Cars, Electric Traction)

Trolley Systems, vii, 186-91, 197-200;

underground wires in, 11-14

Trombones, iv, 231

Trompe, air compressor, v, 89-91

Tropic Birds, xii, 253

Tropical Diseases, xiv, 356-7;

racial immunity to, xv, 48, 50, 51

Tropical Rain Forests, xiii, 357-66, xiv, 366-70;

woods and other products of, 383

Tropics, civilization in relation to, xv, 123, 124-7;

climate monotony, xiv, 357;

cyclones, i, 136;

dry and rainy seasons, xiv, 352;

frost in, 42;

glaciers in, 54;

health conditions, i, 327, x, 251, xiv, 356-7;

labor in, xv, 126;

land and sea breezes, i, 131;

man's development in, ix, 308-9;

products, remarks on, xiii, 259;

quinine use, 251;

rainfall, i, 109;

rainfall and forests in, xiv, 377;

seasonal temperature layer in, 13;

soil depths, 64;

snow line in, xv, 73;

thunderstorms, i, 151;

vegetation of, xiv, 366-70;

white race in, i, 327, xiv, 344, 356-7, xv, 49-50;

winds, i, 127, 135

Troposphere, i, 20, 383;

turbulent conditions, 293-6

Trotula, x, 36, 37

Trough (meteorology), x, 238, 384

Troughs, oceanic, xiv, 286, 288-9;

earthquakes and, 341

Trough Valleys, xiv, 117-21, 123-4

Trout, xii, 158-9;

wariness of, 139

Troy, siege of, plague at, x, 285

Trucks, Motor, v, 214;

advantages to farmers, vii, 230-1

Trumpet Creeper, xiii, 20

Trumpets, sounding of, iv, 231

Trunk (body), muscles of, ix, 77;

skeleton of, 64-7, 63 (fig.)

Trunk-bearing Animals, evolution, iii, 300, xii, 302

Trunks, tree, structure, xiii, 23-6

Truth, experience as test of, (Sylvius), x, 69;

men's notion of, xi, 243;

scientist's search, vi, 107

Trypanosomiasis, x, 167-79

Trypsin, x, 326

Tryptophane, viii, 351

Tsetse Flies, x, 168-70, xiv, 197, 223

Tuatera, xii, 183-4

Tubercle Bacillus, discovery of, x, 149;

killed by sunshine, 292;

tissue-killing power, 293

Tubercles (lesions), x, 293;

of plants, xiii, 98

Tubercular Lesions, x, 293;

radiation treatment of, 384

Tuberculin, x, 150, 216

Tuberculin Test, x, 372

Tuberculosis, x, 289-94;

campaign against, 171, 172, 175-6, (France), 290-2;

climatic treatment, i, 331;

contraction of, from consumptives, i, 326, x, 293;

darkness and, 253, 290, 291;

diagnosis, 216-17, 372;

discovery of bacillus of, 149, xvi, 184;

diseases leading to, x, 292;

Galen's studies of, 30;

germ of, 195, 292;

immunity to, 207;

in warm and cold-blooded animals, 206;

Koch's studies of, 149-50, xvi, 184;

local infections, x, 293;

lowered blood pressure in, 336;

outdoor treatment, 240-1, 291;

pain of, xi, 118;

portal of entry of germ, 198;

predisposition inherited, 235;

racial susceptibility to, xv, 49, 50, 51;

spinal, x, 92

Tubers, xiii, 23, 24 (fig.), 218

Tuileries, invasion (1848), xi, 331

Tulips, in lily family, xiii, 184

Tulip Tree, xiii, 271-2, 318

Tumbleweeds, seed dispersal, xiii, 345

Tumors, radiation treatment of, x, 383

Tundra Vegetation, xiii, 381

Tungsten, in steel alloys, xiv, 238;

symbol and atomic weight, viii, 383

Tungsten Lamps, vi, 267, 268;

candle power, iv, 352;

due to Acheson, vii, 300

Tunicates, xii, 19-20, 129

Tuning Forks, record of, iv, 214-15 (fig.);

reenforcement and interferences of sounds, 219, 220-1;

resonance columns and, 227-8;

sound production by, 197;

synchronous vibration, vii, 118;

vibrations of, iv, 224

Tunneling Machines, iv, 122-4, 260-1

Tunnels, compressed air use in, iv, 129;

heat encountered in building, iii, 121, xiv, 13-14;

hot water encountered, xiv, 144;

sounds of trains in, iv, 236

Tuns (shells), xii, 73-4

Tupaias, xii, 367

Turbans (shellfish), xii, 71-2

Turbinates, of nose, x, 341

Turbines (see Steam Turbines, Water Turbines)

Turf, xiii, 183

Turf Grasses, xiii, 181

Turgenev, Ivan, brain weight, xv, 39

Turgor of Leaves, xiii, 102, 103, 114

Turin, position toward Alps passes, xiv, 240

Turkestan, wild horses of, xii, 307

Turkey, coverings of women in, xv, 254;

opium in, viii, 253;

tobacco production, 258

Turkey Buzzards, xii, 260

Turkeys, xii, 261

Turkish Empire, extent of conquests, xiv, 308-9

Turks, invasion of, through Danube Valley, xv, 138;

migration and conquests of, xiv, 308-9, 311

Turner, astronomer, ii, 301, 343;

on Halley, 86

Turning Effort (see Torque)

Turnip, family and origin, xiii, 197, 224;

swelled root, 19;

vitamines in, x, 262, 266, 268

Turpentine, chemistry of, viii, 51, 240;

in medicine, Galen's use of, x, 30;

specific gravity of, iv, 109-10

Turquois, iii, 340-1

Turret Lathes, v, 52-3

Turtles, xii, 182, 185-94;

absence of fear, xi, 136;

egg-teeth of, xii, 205;

heart of, ix, 84;

Mesozoic, iii, 295;

regeneration in, xii, 170;

shell of, xv, 18;

under-shield of, xii, 184

Tuscarora Deep, xiv, 341

Tusks, evolution, iii, 300, xii, 302;

of walruses, 335

Tusk Shells, xii, 58, 74

Twentieth Century Science, xvi, 195-8

Twilight, i, 167, 384;

duration, 18

Twine Binders, v, 247-8, 381

Twinleaf, distribution, xiii, 351

Twins, identical and nonidentical, ix, 44, 327, xv, 27

Twisters, Texas, i, 60, 384

Two-phase, defined, vi, 203-4, 242

Tycho Brahe, ii, 14, 45-8, iv, 95, xvi, 102;

as astrologer, ii, 21;

eclipse of 1560 and, 210;

new star seen by, 12, 331;

Kepler and, 49, 50;

star catalogue of, 300-1

Tylor, Prof. E. B., "Anthropology" of, xv, 4;

on English spelling, 177

Tyndall, fog signal studies, i, 189, 190

Tyndall Effect, viii, 315

Type, invention, v, 300;

movable, Chinese, xv, 179

Typesetting Machines, v, 307-12

Typewriters, development, v, 312-13, 380, 381;

to take spoken words, 331;

used in telegraphy, vii, 112-13

Typhoid Fever, x, 286-88;

consumption from, 292;

death rate, viii, 321-2, x, 286, 288;

discovery of germ, xvi, 185;

feeding in, ix, 319;

from water pollution, xiv, 140;

germ, x, 194, 287-8;

germs destroyed by chlorine, viii, 86;

germ diagnosis, x, 215, 216;

immunity to, 205, 207;

inoculation against, 208, 217;

named by P. C. A. Louis, 108;

portal of entry of, 198;

prevention of, 171, xv, 49;

water pollution and, viii, 318-19, 321-2;

wells and, iii, 121

Typhoons, i, 136, 384;

locating of, 279-80;

signals (China), 283

Tyrannosaurs, iii, 290

Tyrian Dye, xii, 72

Tyrol, hail crosses, i, 341;

lakes of, xiv, 200

Tyrrhenian Basin, xiv, 291

U-boats, motors used, vi, 239

Uganda, sleeping sickness in, xiv, 223

Uinta Mts., xiv, 83, 98, 226-7, 229;

fault scarp of, 230;

little metamorphism in, 234;

no igneous intrusions in, 228, 230;

river canyons of, 83, 166

Ulcerated Teeth, electric treatment, vii, 237

Ulloa, Admiral, astronomical studies, ii, 179, 221

Ulloca's Rings, i, 184, 384

Ultramicroscopic Organisms, x, 200

Ultraviolet Rays, iv, 358 (fig.);

absorption in upper air, i, 16;

actinic effects, iv, 365-6, vii, 250;

effects on barium, 254;

frequency of vibration, 260;

in therapeutics, 253;

fluorescence from, iv, 379;

luminosity of objects in, 378;

ozone produced by, i, 16;

radiant energy of, iv, 366;

transmitted by æther, vi, 119, 269;

use of, in medicine, iv, 51;

wave lengths of, 365, 366

Ulugh Begh, ii, 39, 300

Umbel, flower form, xiii, 50, 200

Umbra, of shadows, iv, 332

Umbrella Type Generators, vi, 362

Unclean Diseases, Jewish laws on, x, 15

Uncleanliness, air poisoning by, ix, 270, 352;

diseases from, x, 290, 311;

plagues due to, xv, 49

Uncompahgre River, iv, 172, 173

Unconformities (geology) defined, iii, 171, 383;

oldest known, 175;

what they represent, 176

Unconscious Actions, xi, 27;

from habit, 254-5

Unconscious Mind, xi, 47;

in reasoning, 245-6

(see also Subconscious Mind)

Unconsciousness, from excessive breathing, ix, 266-7

Undamped Waves, vii, 273, 289-90, 291

Underclothing, proper materials, x, 307, 308;

soiled, injuriousness of, 310

Underfeeding, results, xi, 370

Underground Streams, iii, 116, xiv, 149-50;

springs and, iii, 117

Underground Transmission, vii, 11-14, 24-31;

in telephone systems, 104, 105

Underground Trolley System, vii, 187, 189

(see also Third Rail)

Underground Water (see Ground Water)

Undermining, of rocks, xiv, 131

Undernutrition, due to under-chewing, ix, 228

Undershot Wheels, v, 76

Underwriters, National Board of Fire, vii, 53-4

Underwriters' Code, vii, 54, 57, 58, 61, 62

Unfit, Survival of, xv, 27

Unger, xvi, 166, 167

Ungulata, xii, 300-31

Unicellular Plants and Animals, xii, 10, xii, 166, 167;

composition and life, ix, 48-9;

food needs of, 33;

food procuring by, 12-15, 19;

motions of, 73, 74;

perception of light and shade by, 105

(see also Protozoa)

Unicorn Plant, fruit, xiii, 57 (fig.);

seed dispersal, 343

Union Pacific Railway, Rocky Mountain pass of, xiv, 76

Unions, chemical, viii, 20-1

United States, aerial mail service, i, 44;

animals (carnivorous), xii, 337, 340, 342, 349, 350, 363, 365;

Atlantic coast, xiv, 25, 45, 246-7, 249-50,

(see also Atlantic Coastal Plain);

Atlantic coast rivers, 167;

automobile industry, v, 213-14;

bats of, xii, 371;

beet sugar production, xiii, 216;

birds of, xii, 254-69;

bison of, 329;

brontides, i, 196;

bubonic plague measures, x, 164;

buildings overheated, i, 323;

building stones, iii, 371-2;

coal and coal beds, 343, 345-8;

coal supply, v, 172;

coffee consumption, xiii, 232;

corn crops, critical period, i, 248;

cotton production, early, v, 270;

crop forecasts, i, 251;

dark days, 56-7;

deer species in, xii, 317-18, 322;

deserts of, xiv, 380;

dust deposits, i, 54-5;

dust in west, xiii, 344;

English sparrow in, xv, 21;

fire losses in rural districts, vii, 231;

first locomotive, v, 378, 378-9;

fish of, xii, 151-64;

flies of, 120;

food and vitamine question, x, 267-8;

forests, xiii, 366-73, xiv, 239, 372-4;

forests, national, xiii, 371-2, xiv, 239;

forest fires, i, 48-9, 56-7;

fresh-water mussels of, xii, 65-6;

frogs of, 180, 181;

geological works on, xiv, 171;

glacial topography in northeast, 60-2, 170-1;

gypsum production, iii, 376;

hailstorm insurance, i, 344-5;

high temperature record, i, 209;

history in relation to physiography, xiv, 61-2, 191-5, 242-3, 249-50,

xv, 136;

Indian summers, i, 361;

influenza pandemics, x, 294-5;

iron and steel industries, xvi, 175;

jute production, xiii, 243;

land leveling rate, iii, 31-2;

land policy, xiv, 384;

lava plateau of northwest, 104, 164, 170, 172, 188

(see Columbia Plateau);

lengthened life in, x, 291;

lightning losses, i, 156;

lizards of, xii, 207, 208;

loess deposits, xiv, 72;

medical practice, history of, x, 104, 115-16, 121-5, xvi, 185-6;

medical schools, xvi, 181;

metal products, iii, 356-70;

meteorological organization, i, 212-13, 215-17, 221, 222;

mineral springs, xiv, 143-4, 145;

newts of, xii, 172;

opossums of, 275;

ore deposits, monographs on, xvi, 173;

oyster industry, xii, 61, 62;

Pacific coast (see Pacific Coast);

paper-making, v, 292;

pellagra in, x, 265, 268;

petroleum and natural gas, iii, 349-51, 353, 354, 355, v, 172-3;

phenological observations, i, 254-5;

plains, coastal and interior, xiv, 213-15;

potash sources, viii, 279;

power plants, viii, 74-5;

prairies, xiii, 373, 374, xiv, 380, 383;

public health fellowships, x, 172;

rainfall i, 110, 110-11, 112, xiv, 352, 360, iii, 113;

rodents of, xii, 288, 290, 293-6;

salt deposits, iii, 374-5;

scurvy in, x, 266;

seasonal advance rate, i, 256;

smoke costs, 64;

snails of, xii, 71;

snakes of, 218-25, 232-8;

snowfall, heaviest, i, 118-19;

specialization of different parts, xv, 131-2, 203;

standard units used in, iv, 45-6, 69;

summer of 1816, i, 359-61;

tea consumption, xiii, 231;

telegraph system, vii, 107-8;

thermometer scale used in, iv, 136;

thunderstorms, vii, 218;

toads of, xii, 176;

tobacco production, xiii, 256, 257, 258, 259;

transportation problem, vii, 194-5;

tuberculosis in, x, 290, xv, 49;

turtles of, xii, 189, 190, 191;

typhoid fever, viii, 322, x, 286;

volcano, only active, iii, 103;

water consumption, viii, 324-5;

water filtering in, 319, 320;

water power, v, 83-4;

water supply by wells, iii, 118;

weather prophets, i, 243;

weeds, xiii, 353-4;

western plateaus, xiv, 220;

western rivers and lakes, 188;

wheat cultivation, xiii, 211;

windmills, i, 37-8;

winds, 128, 133-4;

World War chemical and medical services, x, 176-83, 186, 187-8;

World War disabled, care of, 189-91;

yellow fever extermination, 162

U. S. Army, chemical warfare service, x, 187-8;

medical corps in World War, 177-83, 186, 187;

yellow fever campaign, 159, 160-2

United States Bureau of Fisheries, xii, 155

U. S. Bureau of Standards, aeronautical research, i, 51;

lightning statistics, 156-7

United States Forest Service, xiii, 371-2;

aeroplanes in, i, 48-9

U. S. Hydrographic Office, i, 273, 277

United States Navy, cold-air machines, v, 353;

electricity on ships, vii, 326-35;

meteorological unit, i, 311;

ocean surveys of, xiv, 283;

radio control of ships, vii, 284

U. S. Public Health Service, x, 162, 164, 175

U. S. Signal Service, i, 282-3;

meteorological observations, 216, 220

U. S. Weather Bureau, agricultural service, i, 252, 256-7;

bulletin on temperature and foods, 268;

cloud pictures, 103;

code, 234;

establishment, 216;

fog classification, 95;

forecasts of various kinds, 239-40, 242;

frost predictions, 260;

functions, 7-8;

kiosks, 267;

library, 268-9;

marine division, 273, 275-6, 281;

organization, 222;

question answering, 359;

snow surveys, 118;

Spanish war services, 309;

storm predictions, vii, 218;

sunshine recorder, i, 86-7;

term hours, 203;

terms used, 107, 108, 136;

thermometers, 74, 75;

tide predicting machines, v, 327;

triple registers, i, 87-8;

vanes used, 82;

weather maps, 228, 230, 232-7;

wind-aloft maps, 230, 231, 233;

wireless reports, 280

Units, iv, 384;

absolute and gravitational, 64-5;

atmospheric pressure, 121, 123;

electrical, 261, 284-5;

heat, 154;

magnetic force, 249;

power, 80;

work and energy, 79-80

(see also Weights and Measures)

Universal Ether (see Æther)

Universal Soul, or pneuma, x, 27, 29

Universe, electricity the basis, vi, 107-8, 113, 118;

elements, 108-9;

energy of, unchanging, iv, 40;

evolution, ii, 366-84;

geocentric conception, ii, 9-10, 34-5;

Greek theories, xvi, 76-7, 77-9, 80, 81-2, 84, 186;

magnetism pervading, vi, 40;

primary concepts, iv, 14-15;

shape of visible, ii, 352-3;

stellar, 294-9;

total available heat of, iv, 193

Universities, founding of European, x, 38, xvi, 100;

revival of learning through, ii, 11-12

University of Pennsylvania, park in grounds, xi, 188

Unknown, uneasiness in face of, xi, 224, 225

Unsaturated, defined, viii, 382

Unsaturated Paraffins, viii, 230-2

Upper Air, composition, i, 10-11, 16;

exploration, 18-19, 20-3;

rarity, 17;

sun corpuscles in, 144, 146, 158, 159, 160;

temperatures, 19, 20

(see also Stratosphere)

Ural Mountains, antiquity of, xiv, 96

Uraniborg Observatory, ii, 45, xvi, 102

Uranium, atomic number, viii, 183, 309;

radioactivity, 184, 185, 186;

symbol and atomic weight, 383

Uranus, atmosphere, ii, 250;

comet families, 271;

discovery, 15, 104, 254, 255, 267, 272;

habitability, 250;

Neptune and, 268-9, 270;

orbital deviations, 67, 79, 271;

photographic study, 183;

rotation period, 377;

satellites, 105, 268;

size and orbit, 162-3;

weight, 76, 77

Ure, chemist, xvi, 163

Urea, artificial production, xvi, 142, x, 279, 329;

composition and amount, 342;

composition and functions, viii, 230, 353-4;

in amine group, 215;

production and disposal of, x, 279, 329, ix, 284, 285

Uremia, x, 346

Ureter, ix, 273

Uric Acid, viii, 230, 354, x, 342-3

Urinalysis, x, 378

Urinary Tract, as Infection center, x, 220

Urine, acidity and alkalinity of, x, 281;

albumen in, 378;

amount and excretion, 379;

amount, on what dependent, ix, 274-5;

constituents and disorders of, x, 342-6;

Corbeil's work on, 37;

formation stages, ix, 273;

nitrogen in, 282;

salt in, 273;

sugar in, 291, 292-4;

urea in, 284;

waste products in, x, 270

Urochords, xii, 129

Urodela, xii, 169, 170-3

Ursa Major, changes in, ii, 306;

spiral nebulæ, 363-4;

system, 122, 343, 344

Utah, arid topography of, xiv, 42;

bad lands, 82;

cliff topography, 88;

mining products, iii, 360, 361-2, 362, 363, 368;

plateaus, xiv, 220, 222;

subsidence, iii, 152;

Uinta Mountains, xiv, 83;

volcanic fields of, 317, 318

Uteroplacental Circulation, discovery of, x, 94

Vaccination, discovery, x, 100-3, 207-8, xvi, 127;

present extent, x, 103;

success of, 217, 288

Vaccines, autogenous, x, 218;

in focal infection diseases, 226

Vaccinia, x, 100

Vacuum Balloons, v, 222-3

Vacuum Cleaner, iv, 127, v, 137, vii, 83-4;

atmospheric pressure in, i, 25;

for barn uses, vii, 228

Vacuum Machine, iv, 127

Vacuum Refrigerating Machines, v, 354-6

Vacuums, boiling point of water in, v, 354;

detonation from filling, vii, 211;

early attempts to obtain, iv, 29-30;

electrical nonconductors, 259;

electric discharges in, 317-18;

falling bodies in, 97;

Gessler's and Crookes's x, 183-4;

heat, v, 345-58;

high, iv, 127, vii, 376;

nature's abhorrence of, iv, 27, 114;

of steam condensers, vi, 355;

Pascal's studies, xvi, 110;

sound in, i, 186, iv, 195

Vacuum Tube Generators, vii, 274, 276-8, 291

Vacuum Tube Receivers, vii, 270, 278-80

Vacuum Tube Rectifiers, vi, 339-41

Vacuum Tube Repeaters, vi, 125

Vacuum Tubes, cathode rays in, iv, 317;

Gessler's, x, 183-4;

use in wireless service, vi, 125, 339-41, vii, 277-80

(see also Crookes Tube, Coolidge Tube)

Vagus Nerve, xi, 30

Vail, Theodore N., vi, 87

Valence (chemistry), viii, 93-4, 382;

in periodic classification, 178, 180-1, 179-80;

ionization and, 122;

table of, vii, 384;

variable, viii, 94, 179, 189;

variable in catalyzers, 102;

zero, 178, 181

Valeric Acid, viii, 220

Valley Breezes, i, 131, 132, 377

Valley Glaciers, iii, 60, 62-3, 67

Valleys, air currents, i, 294 (fig.), 296;

drowned (see Drowned Valleys);

fault-made, xiv, 117-21, 127-8;

glacial, iii, 64, 66, xiv, 56-8, 259-60;

hanging, iii, 65, xiv, 57;

historical importance of, xv, 138-9;

longitudinal in folded strata, xiv, 93, 94-6, 98, 226, 229;

people of, xv, 122;

rift or trough, xiv, 117-21, 123;

river (see River Valleys)

Valley Trains, iii, 68

Valliere River, tributary changes, xiv, 184

Valparaiso, harbor of, xiv, 265

Valve Gears, inventions, v, 379

Valves, of heart, ix, 204;

leaking, 206-7

Valvular Heart Disease, x, 332

Vampires, xii, 369, 371-2

Vanadium, use and occurrence, xiv, 238;

symbol and atomic weight, viii, 383

Van Deventer, obstetrician, x, 80

Van Drebel, Cornelius, v, 196

Vanes, wind, i, 82, 384

Vanessas, xii, 117

Van Helmont, Jean Baptiste, x, 67-9, 71, xvi, 108, 110, 111, 119, 163;

recipe for creation of mice, x, 139

Van Hise, geological work, xvi, 172-3, 174

Vanilla, xiii, 259-60;

chemical composition, viii, 239, 251

Vanity, clothes due to, xv, 253, 255;

impulse of, 185

Van Maanan, astronomer, ii, 153, 314, 363

Van Swieten, x, 77, 104

Van't Hoff, xvi, 164

Vapor Baths, temperature of, x, 251

Vapor Pressure, iv, 167-8, viii, 303-5

Vaporization, latent heat of, iv, 173-4

Vapors, condensation of, viii, 304

Variable Stars, ii, 324-30;

collision theory, 327, 329, 333;

color, 296;

discoveries by Bailey, 146;

in star clusters, 337, 338;

inception of study, 16;

sun, 171, 187

Variability, in living things, xiii, 326-7

(see Variation);

meteorological, i, 384

Variation (biological), xiii, 326-36, xv, 22-3, xvi, 151;

causes and perpetuation, ix, 327, 328-9, xvi, 153;

in human beings, xv, 27;

in plants, xiii, 326-36;

meristic and substantive, xvi, 155;

new species developed from, xv, 24-5;

principles understood in Egypt, xvi, 72;

selection and perpetuation, xvi, 154-5

Varieties, crossing of, results, ix, 333-4, x, 231, xiii, 332-3;

defined, 329-30;

mixture, 147;

origin, 326-35

Variola (smallpox), x, 100

Varney, B. M., i, 296

Varnishes, ancient knowledge of, viii, 269;

chemistry of, 264-6;

drying oils in, 245, 247

Varro, on weather vanes, i, 68

Varus, defeat of, i, 307

Vascular Cryptograms, alternation of generations, xvi, 166

Vascular System, xiii, 65-6;

not in mosses, 69;

first appearance, 303, 304, 306

Vasoconstrictor Center, ix, 215-19

Vasodilator Center, ix, 219-21

Vasomotor Center, ix, 215

Vasomotor System, efficiency, how developed, x, 238-9, 240, 241;

heat loss, regulation by, ix, 311

Vassenius, astronomer, ii, 179

"Vaterland," steamship, v, 193

Vaughn, on anaphylaxis, x, 214

Vedas, song to day-god, ii, 23-4;

weather proverbs in, i, 67

Veery, xii, 269

Vega, Arabic name, ii, 39, 302;

color, 297;

Sirian star, 115;

spectrum, 116

Vegetable Acids, viii, 222-3

Vegetable Fats, viii, 244, 246;

vitamines absent in, 369, ix, 33, x, 259, 260-1, 262

Vegetable Kingdom, chemistry of, viii, 191;

food source of man, ix, 24;

how distinguished, xii, 14-15, xiii, 13-14;

relation to animals, viii, 334

(see also Plants)

Vegetable Oils, composition and energy value, ix, 28

Vegetables, calory loss in preparing, ix, 299;

cooking of, effects, viii, 368;

food value, 365, ix, 34, 280, 300, x, 259, 260, 262, 266, 273, 279;

freezing prevention, iv, 161;

frost danger point, i, 258;

green bile from eating of, ix, 275;

origin of common, xiii, 221-4, xiv, 382

Vegetable Sheep Plant, xiii, 379

Vegetable Silk, viii, 255-6

Vegetarianism, protein supplies in, ix, 280;

remarks on, 285

Vegetation, defined, xiv, 363;

determined by climate, and soil, 363-81;

effect of light and darkness on, xiii, 84-90;

effect on winds, i, 292-3;

electrical stimulation, vii, 351-3;

growth in tropical forests, xiii, 358-9, 360, 364-5;

optimal temperature, xi, 51;

past and present, xiii, 174, 175;

phosphorescence of decaying, i, 346;

soil and rock protection by, xiv, 42;

types on what dependent, xiii, 12

Vegetative Nervous System, x, 352-3

Vehicles, evolution of, v, 17

Veins, of body, ix, 191, 195, 197-8;

of body, bleeding from, x, 39;

blood in, carbon dioxide content, ix, 263, 264;

blood in, color of, 260-1;

functions in circulation of blood, x, 63-65, 334;

connections with arteries, ix, 192-3 (fig.) 197;

valves of, 222;

of leaves, xiii, 32-3, 37 (fig.), 79

Veins, Mineral, defined, iii, 383-4;

how formed, 126

Velocity, iv, 56-7, 384;

acceleration of, 57 (see Acceleration);

energy from, 78;

momentum and, 62-3;

Newton's laws and high, ii, 80, 81;

of falling bodies, iv, 65;

relation to power in machines, 92;

required on centrifugal railroads, 74;

unity of, 64

Velpeau, x, 130

Vena Cava, ix, 197-8, 201 (fig.), x, 334;

waste fluids emptied into, ix, 222

Vena Contracta, v, 89-90

Venereal Diseases, contagion demonstrated by Saliceto, x, 39;

quacks and, 76

Venice, commercial growth and decline, xiv, 308

Venomous Snakes, xii, 224-38

Ventilation, i, 321-2, viii, 331-2, ix, 267-70, x, 237-8;

air moving systems, i, 323;

electrical, on battleships, vii, 330-1;

katathermometer in, i, 320;

importance of, to infants, ix, 352;

ozone, vii, 353-4;

perception of need of, ix, 97

Ventral Segments, of vibrations, iv, 217

Ventricles, of brain, xi, 29

Ventricles, of heart, 201 (fig.), ix, 203, 204-5

Venus (planet), ii, 190-2;

atmosphere, 130-1, 191, 192, 246;

life on, 246-7;

lucid planet, 264;

non-rotation theory, 377;

orbit, 50, 162, 163;

phases of, xvi, 103;

phases, discovery of, ii, 54, 83, 94;

size, 162, 163;

stellar magnitude, 296;

transits, 58, 129;

weight, 76, 77

Venus's Flower Basket, xii, 31

Venus's Flytrap, xiii, 40-1, 64 (illus.)

Vera Cruz, harbor of, xiv, 266

Verbal Images, xi, 222

Verdant Zones, i, 259, 384

Verdun, defense of, xiv, 90-1

Verkhoyansk, Siberia, i, 209-10

Vermilion, viii, 170

Vermont, marble production, iii, 189, 371;

summer of 1816, i, 360

Verne, Jules, novel by, i, 170

Verrazano, voyage of, xiv, 310

Vertebrae, of spine, ix, 64, 65 (fig.);

origin from coelom, xii, 87

Vertebrates, xii, 127-9;

characteristics of, 132;

classification, iii, 260;

evolution, 287 (chart), xii, 167;

geological history, iii, 281-306;

reproduction in, xv, 54;

resemblances among, 55-6;

structure and organs of, 55-6

Vertical Distances, xi, 185

Verworn, Dr. Max, quoted, xi, 67

Vesalius, Andreas, x, 46, 50-3, 65

Vesico-vaginal Fistula, x, 122

Vesta (planet), ii, 255, 257

Vestal Virgins, cult of, viii, 89;

fire of, xv, 234

Vestibule, of head, ix, 90

Vesuvius, Mount, cone of, xiv, 100, 225;

eruptions of, iii, 99-100, xiv, 313, 326, 338;

flashing arcs, i, 194;

material ejected, xiv, 326-7;

only active European volcano, 316;

soils and vegetation, viii, 339;

soils on, xiv, 329

Vetches, in pea family, xiii, 198;

leaves, 113;

used in soil enrichment, 98

Veterans of World War, care of, x, 189-91

Vibration, Vibrating Bodies, iv, 86-8, 196;

amplitude of, 211;

elasticity and, 156;

frequency defined, 205, 382;

interferences of, 218-22;

of elastic bodies, ix, 98-9, 100-1;

of rods, iv, 213-15, 223-4;

of strings, 216-17, 223;

period of, 196, 205, 383;

rate of, on what dependent, 213, 223;

sound production by, 195-6;

sympathetic, 225-6, vii, 118, 261-2;

transverse and longitudinal, iv, 215

(see also Waves)

Vibrators, electric, vii, 87

Vibgyor, i, 165

Vichy Springs, xiv, 145

Vickers-Vimy Bomber, v, 233

Vicksburg, capture of, xiv, 194

Victoria Falls, iii, 49, xiv, 131-2;

forests at, 369-70

Victoria Nyanza, xiv, 120, 204

Vicuñas, xii, 313

Vienna, siege of, xiv, 308-9

Vienna Meteorological Congress, i, 219, 220

Vigo, Juan del, x, 155

Vikings, history of, xiv, 261

Vilmorin, work on sugar beet, xiii, 216

Vincent, George E., x, 175

Vinci, Leonardo da (see Leonardo da Vinci)

Vinegar, acetic acid in, vi, 111, viii, 220, 293;

from cider, 219;

in preserving, 372;

production of, 248, 249

Vines, nature and methods, xiii, 27-8;

tendrils, 111-12;

of tropical forests, 361-2

Vineyards, and hailstorms, i, 343

Vinland, xiv, 261

Violence, and will, xi, 264

Violet (color), complementary color of, iv, 367;

primary color, 366;

vibration rate, ix, 115;

wave lengths, i, 165, iv, 360

Violet Light, fluorescence from, iv, 379;

of mercury arc lamp, 282, 283;

use of, in medicine, 51

Violet Ray Machine, x, 183-4

Violets, dogtooth, xiii, 184;

fertilization, 120;

seed dispersal, 56, 339;

stemless, 15

Violin, intervals on, iv, 208;

resonance chamber, 223

Violin-Piano, vi, 97

Vipers, xii, 229-32;

ancestry of, 225;

hedgehogs and, 367

Virchow, x, 128-9;

"Cellular Pathology," xvi, 182;

founder of cellular pathology, x, 119;

malaria studies, 156-7

Vireos, xii, 268

Virginia, former volcanoes of, xiv, 318;

mineral springs of, 143;

rainfall, i, 338

Virginia Creeper, xiii, 28

Virility, from cross breeding, xiii, 120, 122-3

Viruses, attenuating principle, x, 141, 142, 143;

filterable, 141, 161

Viscachas, xii, 289;

acquisitiveness of, 292-3;

prey of boas, 215

Viscera, emotion effects, xi, 134-5;

insensible to pain, 118

Visceral Senses, xi, 63-4

Vishnu's Temple, Grand Canyon, xiv, 84

Visibility, i, 384; in aviation, 303;

scale, 314

Vision, (sense) xi, 83-97;

compared with hearing, 98;

defects of, ix, 112-14;

distance of distinct, iv, 342, 343;

limits (wave lengths), 360, 361;

motions connected with, ix, 82;

operation, vi, 271-3;

persistency of, iv, 346-7, v, 329, vi, 155

(see also Sight)

Vis Plastica, iii, 14

Visual Hallucinations, x, 358, xi, 91

Visual Purple, of retina, xi, 96

Vital Capacity, defined, x, 339

Vital Function, tests of, x, 376-9

Vitality, of infants, ix, 352

Vital Knot, ix, 257

Vital Processes, chemical nature of, viii, 353, 355, ix, 34;

chemical control of, 167-72;

control of breathing, 256-7;

functional metabolism of, 295-6;

no energy consumed in, viii, 367;

past theories of, x, 69, 76-7, 84, 85, 86

Vitamines, viii, 362, 369-70, ix, 33-4, 35-6, 347, x, 256-68

Vitreous Electricity, iv, 258

Vitruvius, work on architecture, xvi, 98

Vividness, in associations, xi, 205

Vlacq, Adrian, xvi, 104

Vladivostok, harbor of, xiv, 267

Vocal Cords, ix, 83

Vocal Organs (see Speech Organs)

Vocations, avocations and, xi, 375-7;

choice, 276, 358-61

Vocational Guidance, xi, 358-61

Vocational Training, of veterans, x, 190

Voice, evolution of, in amphibians, xii, 170, 178;

expressiveness of tone of, xv, 144;

fear effects on, xi, 132;

modulations of, iv, 209, 232;

pitch in public speaking, 232;

quality of, to what due, 233;

range of human, ix, 99;

sound of, in dense atmosphere, 31-2;

use of, in communication, xv, 151-2

Voice Organs, in birds, xii, 248-9

Voice Production, motions of, ix, 83

Volatile Liquids, iv, 174

Volcanic Activity, distribution, iii, 100 (map), 227 (map), xiv, 314-21;

hot springs and, 143, 144;

of past ages, iii, 177, 191, 196, 197, 203, 219, 226-9

Volcanic Belts, xiv, 314-17

Volcanic Bombs, xiv, 323

Volcanic Cones, xiv, 100-2, 225;

oceanic, 277, 289

Volcanic Dust, xiv, 324;

from Krakatoa, i, 18, 57-8, iii, 101, xiv, 325;

from Tomboro, i, 360;

from various eruptions, iii, 102-3;

in atmosphere, i, 53, 57-8, 360;

in ocean, iii, 54-5, xiv, 325;

soils of, xiv, 69, 329;

temperature effects, i, 58-9, 360;

thick deposit in Colorado, iii, 229;

wind carried, xiv, 327, xiii, 344

Volcanic Earthquakes, xiv, 338-9

Volcanic Eruptions, iii, 99-103, xiv, 321-9;

earthquakes and, iii, 93-4, xiv, 338-9;

temperature effects, i, 58-9

Volcanic Islands, xiv, 277, 289, 314, 316;

new, 319

Volcanic Necks, iii, 111;

of Mount Pelee, 103

Volcanic Rocks, iii, 13, 384, xiv, 99-100;

distribution in western America, iii, 227 (map);

extrusive, xiv, 105;

land forms in, 100-5

Volcanic Soil, xiv, 69, 329

Volcanoes, iii, 99-110, xiv, 312-29;

carbon dioxide from, i, 13;

distribution of active, iii, 100 (fig.), 227 (map), xiv, 314-21;

earthquakes and, iii, 93-4, xiv, 331, 338;

energy stores and harnessing of, v, 178-80;

fire source, xv, 230;

in sea, xiv, 285-6;

materials from, 104, 323-4

Voles, xii, 285, 290

Volga River, base level of, xiv, 164;

continental character, 153

Volition, xi, 259-67 (see Will)

Volkmann, on tedium, xi, 195;

pupil of Muller, x, 118

Volta, Alessandro, vi, 18-19, xvi, 122

Voltaic Cells, iv, 272, 295-6

Voltaic Pile, vi, 18-19, 61-2, 72;

invention, xvi, 122, 189

Voltaire, messengers, xvi, 11;

naturalism of, 111, 117

Volterra, soffioni of, v, 179

Volt-coulomb, iv, 294

Voltmeters, vi, 62, vii, 153-65, 376;

ammeters used as, 167-8;

electromagnetic, 171;

galvanometers as, 179;

invention, vi, 23;

Kelvin's, 24

Volt Ratings, vi, 53;

importance, 9, 72

Volts, Voltage, iv, 280-1, 284, vi, 53-4, 57, vii, 376;

amperage, resistance and, (see Ohm's Law);

changed by converters, vi, 345-8;

dangers of excessive, 9, 72;

decrease in transmission, vii, 189;

direct current, 164;

high, in smoke precipitation, vi, 164;

high, in transmission, 159-61, 331-2, vii, 10-11;

induced and generated, 370;

magnitude, on what dependent, 139, 144-5;

measurement (see Voltmeters);

regulation, vi, 188, 328-9, 346;

regulation in automobiles, vii, 144-50;

regulation in motors, vi, 226-8;

residual, 191;

stepped up and down, 309-10;

terminal and generated, 186;

transformation, 159-61 (see Transformers);

watt-seconds in relation to, 82, 85

(see also Electromotive Force)

Voltage Regulators, vi, 188, 328-9, 346

Volume, metric units of, viii, 28;

of gases, laws, 106-8

Volumetric Analysis, viii, 291, 292-5

Voluntary Actions, factors, xi, 260-5

Vomiting, cause, xi, 39

Von Kluck, course of, xiv, 92

Vortices, atmospheric, i, 134-5;

Descartes' theory of, ii, 60

Vosges Mountains, xiv, 87 (map), 90, 117

Vowel Sounds, nature of, xi, 104;

photograph record of, iv, 234

Vries, Hugo de, on mutants, xiii, 333, 334

V-shaped Depression, i, 238, 384

Vulcan (planet), ii, 189

Vulcanizing of Rubber, xiii, 245;

sulphur used in, viii, 77, 257-8

Vulcano, dormant volcano, xiv, 317

Vulcanology, science of, xvi, 38

Vultures, xii, 260

Waialeale, Mount, rainfall on, i, 112

Waiting, slowness of time in, xi, 194, 195, 196

Wakefulness, causes of, ix, 218-19

(see also Insomnia)

Wake Robin, xiii, 176, 183 (fig.)

Wales, Britons in, xiv, 243;

geology of, 271-2;

marriage by capture in, xv, 283

Walking, act and processes, ix, 89-90, 156-8;

balance, how maintained, xi, 31;

chain reflex in, 250;

correct carriage in, x, 305, 306;

as exercise, 304, 317;

high heel effects on, ix, 69;

of children, 351;

of men and apes, xv, 58;

work equivalent, x, 305

Walking Ferns, xiii, 65

Walking Machines, v, 215-16

Walking Stick, ix, 9, xii, 107-8

Wallabies, xii, 278-9, 280

Wall, Dr., on lightning, vi, 14

Wallace, A. R., on distribution of animals, xvi, 140;

on Martian life, ii, 248

Wallis J., mathematician, xvi, 113-14, 115

Wallpack Ridge, xiv, 51

Walnut Tree, antiquity of species, xiii, 324-5;

family, 191;

petals absent, 190;

sexes in, 46, 191;

in U. S. forests, xiv, 373

Walpurgis Night, i, 184

Walruses, xii, 334-5;

in glacial period, xiv, 376

Walschaerts Gear, v, 210

Walter, Dr. B., i, 147

Walter Reed Hospital, x, 189

Walther, patron of Regiomontanus, ii, 40, 41

Wapiti, xii, 317-18;

antlers of, 316

War, "art" of, i, 306;

chemistry in, viii, 262-4;

crowd psychology in, xi, 330-1;

destructiveness of modern, v, 359;

engines of, 359-75;

inventions and, 12, 350-60, 375;

meteorology in, i, 306-15;

science and, xvi, 9;

topographical considerations in, xiv, 92-3

Warblers, colors of, xii, 245-6

War Dances, xv, 307

Warm-blooded Animals, diseases of, x, 206;

temperature regulation in, x, 250, ix, 305

Warm-bloodedness, ix, 305;

advantages, 306-7;

importance of, xii, 244, 271

Warmth, sense of, ix, 93-4, 319-20, xi, 109, 112, 113, 114

Warping (geological), xiv, 35-6, 37, 38-9

Warp Threads, v, 278-9, 281, xv, 244-5, 246 (fig.)

Warren, Dr., x, 125

Wart-hog, xii, 310

War Vessels, first steam, v, 378

Wasatch Mountains, faulting in, iii, 89, 90-2, 152;

fault scarp of, xiv, 117, 122, 124, 230;

parallel beach lines on, 207;

recent uplift, iii, 39

Washing Machines, Electric, vii, 78-82, 90

Washing Soda, viii, 135

Washington, (city), malaria reduction in, x, 300

Washington, (State), earthquakes in, xiv, 331;

forests in, 374;

lava formations, 102, 104, 318

Washington Monument, diurnal gyration, v, 71

Washington Thorn, xiii, 198 (fig.)

Wasps, xii, 125-6;

appearance in Tertiary, 104;

nests of, xv, 266

Watches, balance wheel construction, iv, 148;

historical development, v, 57, 65, 379;

mechanism, 68-72;

precision of modern, 67-8;

radium dials, iv, 380;

screened from magnetism, vi, 32

Watchung Mts., xiv, 111

Water, atmospheric content, viii, 67;

basic element (Thales), xvi, 77;

body needs and uses of, viii, 355-6, 357, 358, ix, 37-8, 173, 233,

246-7, 262, 272, 273, 274, 276;

body percentage of, viii, 348

boiling of, by cooling, iv, 168-9;

boiling point, i, 73, iv, 136, 137, 141, 168, 178;

boiling point and pressure, 170, v, 354, viii, 303;

buoyant power of, iv, 104, 105;

capillarity, viii, 37;

catalyzing power, 103;

chemical composition, 26, 39-40, ix, 26;

chemical properties, viii, 38-40, 355-6;

cleansing agent, 142;

color and taste, 40;

compounds of, 38-9, 70, 79-80, 89, 152-3;

compressibility, v, 106, 107;

cooling by evaporation of, iv, 174, v, 349-50;

critical temperature and pressure, iv, 171-2, 173;

decomposition, viii, 21, 39, 101-2, 134, 184;

density of, iv, 113;

density standard, 111, 112, 149;

distribution of, on earth, xiv, 20-5;

drinking of, and obesity, x, 275;

drinking of, at meals, ix, 229;

electrical conductivity of, iv, 296;

electrolysis of, viii, 30-1;

expansion on freezing, iv, 149-51, 163, viii, 38, xiv, 75;

fire extinguishing by, viii, 57;

fluid temperatures, ii, 244;

foreign substances in, viii, 40-1;

forest requirements, xiv, 377-8;

formed by body tissues, ix, 262;

formed as by-product of salts, viii, 115, 116-17;

freezing of, warming process, iv, 161;

freezing of, while boiling, 169;

freezing point, i, 73, 136, 137, 141, 173;

freezing point, lowered by alcohol, viii, 299-300;

geological work (see Streams, Rivers, Lakes, Ocean);

grass requirements, xiv, 381;

ground (see Ground Water);

hardness of, viii, 151-2, 318, 377, iii, 126, xiv, 147;

heat capacity of, iv, 155, 162-3, 186;

heat conductivity, 176, 179;

heat convection in, 177-8;

heat developed in formation, viii, 95-6;

heating of, mechanical equivalent, iv, 49-50, v, 350;

height of rise in vacuum, iv, 27;

hydrogen produced from, viii, 30-2;

hydrolysis, 39, 217-18;

imperviousness of clay to, xiv, 137;

importance, viii, 36;

in animal body and plants, 348, 355-6;

in carbohydrates, 223, 224;

in carbon-hydrogen cycle, 350;

in protoplasm, ix, 37-8, 282;

in various foods, viii, 362, 363, 364, 365;

infant's need of, ix, 350;

interestingness of, xvi, 14;

ionization of, viii, 123;

"juvenile," xiv, 151-2;

kinetic energy, v, 84-5;

latent heat of, iv, 161, 174, 188, v, 169, 353-4, viii, 38;

laws of, widely known, vi, 106;

mechanical uses (see Hydraulic Machinery);

machines for raising, iv, 26-7;

men's need of, xiii, 101-2;

metabolism affected by, ix, 37-8;

metric measurements of, iv, 111, 112;

a mineral, iii, 308;

mixtures at different temperatures, iv, 153-4;

mixtures with ice, 160-1, v, 353-4;

necessity of, to life, x, 275, ix, 37-8, xi, 66, xiii, 101-2;

of chemical union, viii, 38-9;

of crystallization, 38;

of limestone regions, xiv, 147;

ore deposition by, viii, 199;

origin of life in, ii, 243, 244, xvi, 78;

origin on earth, iii, 160, 163;

oxygen in solution, viii, 35, ix, 182;

photographing objects under, i, 47-8;

physical properties, viii, 37-8, 40-1, 355;

plant fertilization by, xiii, 123, 149-52, 158-9, 160, 161, 165;

plants' storage of, 28, 41-2, 106-7, 378, 379, 380;

plants' use of, viii, 335, 337-8, 347, xiii, 90-6, 101-9, xiv, 65,

377-8, 381, ix, 26-7;

power in atoms, vi, 115;

pressure of, iv, 117-19, v, 94-5, vi, 47-9, 56;

produced by combustion or decay, viii, 61;

produced by volcanoes, iii, 107;

purified by ozone, vii, 354-5;

purification by dissolved oxygen, viii, 40, 111;

purity of flowing, iii, 121;

rate of flow, vi, 68-9, 70-1;

reflection of light by, iv, 373-4;

reflection of objects in, 337;

refraction of light by, 323, 326-7, 331, 373-4;

resistance, v, 190-2;

rock-weathering by, iii, 22-3, 24-6, viii, 194-5;

seed dispersal by, xiii, 346-8;

softening of, viii, 135, 152, 323-4;

soil, xiii, 92;

solvent action and solutions in, viii, 37, 111-13, 120-1, 217;

sound transmission by, v, 107, 108;

sound velocity in, iv, 201;

specific gravity basis, 109, 111;

specific heat of, 155, viii, 37;

states of, iv, 22, 131, 139, 151-2;

supercooled, viii, 113;

temperature in steam engines, v, 139-40;

temperature of greatest density, iv, 149, v, 350;

terrestrial, circulation and sources, xiv, 134-5, 151;

therapeutic uses of, x, 85, 383;

transparency in Lake Tahoe, iii, 154;

weight of, iv, 117, 149, v, 94, vi, 80-1, 147;

within the earth, iii, 109-10, 113-29

Water-bearing Strata, excavating through, v, 116-17

Water Birds, xii, 250-9;

feathers of, 244;

sleeping of, xi, 287

Water Boa, xii, 216

Water Boatmen (insects), xii, 114

Water Bugs, xii, 114

Water Chestnut, source, xiii, 266

Water Clocks, ancient, v, 59-63

Water-cooled Engines, v, 159-61

Water Cress, taste, xiii, 197

Water Dogs, xii, 171

Water-dripping Plants, xiii, 107-8

Water Drops, atmospheric, i, 91-2, 93, 95;

phenomena due to, 150, 166, 175, 177, 183

"Wateree," U. S. S., xiv, 337

Waterfalls, caused by Ice Age, iii, 242-3;

energy of, iv, 81;

in glacial valleys, xiv, 57;

in homogeneous rock, 132-3;

in old and new regions, iii, 33-4, xiv, 48, 49, 57, 159;

types, iii, 44-50

Water Gaps, xiv, 98

Water Glass, viii, 141

Water Hammer, in pipes, v, 84, vi, 254, 364

Water Hemlock, seeds, xiii, 201

Water Jets, digging with, v, 88;

dredging with, 258;

power, 80;

propulsion of boats by, 190;

vena contracta of, 89-90

Water Lilies, Amazon, xiii, 359-60;

class of, 196

Waterloo, Napoleon's indigestion before, ix, 238;

weather conditions, i, 307

Watermelon, xiii, 54, 227;

water content, viii, 365

Water Meters, v, 87-8

Water Organ, v, 110-11

Water Pipes, bamboo stems as, xiii, 183;

bursting of, iv, 151, xiv, 75;

electrical thawing, vii, 336-9;

electrolysis, 188;

rate of flow in, vi, 71;

water hammer in, 254, 364, v, 84

Watering Places, xiv, 145

Water Plethysmograph, xi, 284

Water Power, coal and, xiv, 31, 191;

compressing air with, v, 89-93;

discovery of, xv, 240-1;

early and present use, v, 75-6, 173, xiv, 31;

electricity from, vi, 162-3, 351-2, 361-70;

future possibilities, v, 83-4;

gravity the real power, 76-7, 139;

growing use of, viii, 267, 283;

high head importance, v, 77;

in mountain countries, xiv, 242;

use on farms, vii, 233-4;

"White Coal," v, 174

(see also Hydraulic Machinery, Hydroelectric Plants, Water Jets, Water

Wheels)

Waterproofing, by rubber, xiii, 245

Water Ram, v, 84-6

Water Scorpions, xii, 114

Watersheds, Atlantic-Pacific, xiv, 189-90;

in young and old regions, 158, 161

Water Snakes, xii, 217-18

Water Solubles (vitamines), x, 260, 261, 262

Waterspouts, i, 138, 384;

cores, 299;

lifting power, 356;

superstitions, 335

Water Supply, common sources, viii, 317-18;

from wells, iii, 118, viii, 317-18, xiv, 139-40;

of American cities, viii, 317, 318, 320, 322, xiv, 140-1;

pollution and purification, viii, 41, 317-24, xiv, 139-41;

purification by chlorine, viii, 86, 321;

purified by compressed air, iv, 130-1;

snow sources, i, 118;

typhoid contamination of, x, 287

Water Table, iii, 113, 118, xiv, 136;

rise of, i, 355

Water-tube Boilers, v, 140

Water Turbines, v, 82-3, vi, 361-2, 363-4;

efficiency, v, 170;

at Keokuk Plant, 81-2, 82-3;

of Niagara Power Plant, vi, 372-3, 374-5

Water Vapor, atmospheric, i, 10, 11, 14-15, 76, iv, 183;

precipitation, i, 90-6, 113, 115, 120, 121;

need of nuclei for condensation, viii, 113;

saturated pressure of, iv, 168, 169

Water Wheels, early use, v, 19, 75, 76;

energy used by, iv, 181;

former and modern types, v, 76-7;

invention of, xv, 240-1

(see also Pelton Wheels, Water Turbines)

"Waterwitch," steamboat, v, 190

Water Witches, iii, 123, 124

Water Yam, xiii, 89-90

Watkins Glen, iii, 44, 243

Watson, Sir Thomas, x, 112

Watson, Prof., asteroids of, ii, 256-7

Watt, James, power unit named for, iv, 285;

steam engine, v, 44, 47, 144-6, 376, 377, xvi, 125

Watt, Sir George, book on Indian plants, xiii, 266

Watt, power unit, iv, 80, 285, 310, 312, vi, 84-5, vii, 376;

method of ascertaining, vii, 166;

value in candlepower, iv, 352

Watt-hour, iv, 312, vi, 82;

erg and calorie equivalents, vii, 382

Watt-hour Meters, vii, 174-7

Wattmeters, vii, 172-4, 376;

electromagnetic, 171

Watt-second, vi, 82, 84, 85

(see also Joule)

Wave Length, iv, 196, 213, 214 (fig.), 384

Wave Meters, vii, 292-5

Waves, Ocean (see Ocean Waves)

Waves (vibrations), defined, iv, 196, 384

(see also Light Waves, Sound Waves, etc.)

Wax Candles, viii, 246, 247

Waxes, viii, 245-6, 350

Weak-Mindedness, facial expressions of, xv, 63, 64 (fig.)

"Weaning" Treatments, xi, 248

Weapon Salve, x, 79

Weapons, evolution of, v, 12-13, xv, 102-10, 190-2, 205-21

Weariness, indigestion from, ix, 241

Weasel Family, xii, 347-51

Weasels, xii, 348-9;

storing of food by, 292

Weather, aeronautics and, i, 284, 285;

atmospheric pressure and, 237-8, 241-2;

business dependence on, 261-70;

climate and, 199;

clothing in relation to, x, 309-10;

"comes from west," xiv, 350;

control of animal and plant life, i, 254;

correlation studies, 253;

crops and, 245-50, 252-3;

cycles, 242;

elements and how observed, 70-89;

heights of phenomena, 17, 18;

human effects, 316, 323-4, 330-1;

military importance, 306-15;

modern commenting on, 66;

moon's influence, ii, 201;

predictions for future eclipses, 217;

pressure areas and, i, 135, 218, 237-8, xiv, 349-50;

"recurrence," i, 363;

solar radiation and, 218-19, ii, 186-7, iv, 194;

sun-spots and, i, 16, 242, ii, 186;

variety in relation to efficiency, xiv, 357;

world-wide interrelations, i, 218, 241-2

Weather Bureau (see U. S. Weather Bureau)

Weather Forecasts and Forecasting, i, 224-6, 236-44;

advertising and, 265-6;

aeronautical, 18, 304-5;

agricultural, 256-7;

basis, 135;

frost, i, 260;

history of, xvi, 102, 177;

kites and balloons in, i, 22;

"odds," 314;

rainbows in, 177;

small progress in art, 382;

sunrise and sunsets in, 166;

United States, 216-17

(see also Weather Predictions)

Weather Glass, i, 70

Weather Instruments, i, 68-89

Weather Insurance, i, 269-70

Weather-Making, i, 332-45

Weather Maps, i, 225-36;

"flat," 239, 372;

marine, 273-6;

shipboard, 281;

winds on, 125-6, 134

Weather Observations and Reports, i, 66-89, 213-23;

aeronautical, 304-5, 314;

earliest instrumental, 201;

humidity in, xiv, 353-4;

marine, i, 274-6, 280-2;

used in crop forecasting, 251-2;

World War, 310, 314

Weather Predictions, long range, i, 241-4;

value to farmers, 249-50

Weather Prophets, distribution, i, 243

Weather Proverbs, i, 106, 177

Weather Vanes, ancient, i, 68;

common and scientific, 82

Weather Wells, i, 354, 384

Weathering of Rocks, iii, 22, 384, viii, 194-5, 338;

agencies and processes, iii, 22-9, xiv, 41-3, 62-4, 75-9, 105-6;

determined by character and arrangement of rocks, 44, 79, 130, 133;

in deserts and arid regions, iii, 23, 72, xiv, 41-2, 62, 69, 77-9;

on mountains, iii, 23-4, xiv, 40, 233;

plutonic rocks, 105-6, 107, 110, 112-13

Weaving, historical development of, xv, 243, 244-7;

pattern-making, v, 280-2;

threads, 276, 278-80

Weber's Law, xi, 184-5

Webs, of spiders, xii, 94, 95-6

Webster, Daniel, brain weight, xv, 39

Wedding Presents, xv, 285

Weddings, attendants at, origin of, xv, 282

Wedge, v, 37;

discovery of use, 15;

form of inclined plane, iv, 90;

friction in, 93

Wedge (meteorology), i, 238, 384

Weeds, origin in U. S., xiii, 353-4

Weedy Plantain, xiii, 88

"Weeping Trees," i, 351

Weeping Willow, xiii, 271-2

Weft Threads, v, 278, 280

Wegener, Dr. A., i, 192

Weight, iv, 58, 74, 99, 101;

defined, vi, 81, xvi, 130;

diminished by earth's rotation, iv, 74-5;

errors in perception of, xi, 184-5;

latitude and, ii, 69, iv, 101, 102, xvi, 130;

loss of, in fluids, iv, 104, 105, 106, (fig.), 107;

mass and, 84-5, 110, xvi, 130;

measured by spring balance, iv, 102;

measurement of, by displacement, 103-4, 105;

of gases, gram-molecular method, viii, 109;

units of, iv, 46, 283-4, viii, 28

Weight (bodily), at different ages, ix, 31, 32 (diagram);

metabolism in relation to, x, 271, ix;

reduction of, 302;

rate of reduction by fasting, x, 275

Weight Arm, in machines, v, 22, 26, 31, 32, 33

Weights and Measures, British and metric units, iv, 45-6, 69-70;

practical units, 283-4;

scientific standards, xvi, 129-30

(see also Units)

Weismann, germ plasm theory, x, 230;

on adaptations, xvi, 152

Welding of Metals, i, 33;

electric, iv, 312;

Goldschmidt method, viii, 155

Wells, airlifts in, iv, 130;

artesian, iii, 118-19, xiv, 12, 138;

blowing, i, 353-5, 368;

drilling of deep, iii, 119-21;

drying of, xiv, 136;

gases and minerals in water, 141-2;

Green's drive, v, 380;

locating of, iii, 123-6;

pumping systems for deep, v, 114-15;

sanitary aspects, iii, 121-3, xiv, 139-40;

source of, 138-9;

sunk in granite, 137;

water supply from, iii, 118-19, viii, 317-18

Wells, E. I., on railroads, i, 267

Wells, Horace, x, 124, 125, xvi, 185

Wells, Spencer, xvi, 184

Welsbach Gas Mantles, vi, 264, viii, 252;

invisible rays, xvi, 192

Welsh Language, xv, 162

Welsh People, in Mediterranean Group, xvi, 49;

mountain isolation of, xv, 130

Welts, hypnotic production, xi, 317

Welwitschia Mirabilis, xiii, 380-1

Wentletraps, xii, 71

West Africa, beetles of, xii, 124;

crocodiles of, 199-200;

coast of, xv, 136;

forests of, xiv, 366, 368-9;

hanging valleys in, 58;

harmattan of, i, 134;

monkeys of, xii, 379;

monsoons, i, 131;

python of, xii, 214;

river shrew of, 367;

sleeping sickness, x, 169;

tornadoes of, i, 137

Western American Volcanic Belt, xiv, 315

Western Forest (U. S.), xiv, 373-4

Western Pacific Volcanic Belt, xiv, 315-16

Western Union Telegraph Co., vii, 107-8, 112;

early weather forecasts, i, 216

West Indies, boa constrictor of, xii, 215;

clove production, xiii, 262;

coffee in, 233;

concordant coasts of, xiv, 249;

coral reefs in, 305;

earthquakes in, 331;

hurricanes, i, 136, 375;

hurricane reports, 280-2, 309;

mongooses in, xii, 352;

nutmeg production, xiii, 262;

poisonous snakes, xii, 234;

sea-shells of, 73;

sharks of, 143;

sponges of, 32;

spurge, xiii, 30-1;

vanilla production, 259;

volcanoes of, xiv, 316

Westerly Winds, region of prevailing, i, 128, 129

Westinghouse, George, air-brake, v, 130, 380

Westinghouse Electric Co., machinery for Niagara Plant, vi, 374, 375, 376

Westminster Abbey, weathering effects, iii, 22

West Virginia, natural gas, iii, 355

Wet Bulb Thermometer, i, 78-9, 318, 384

Wetness, exposure to, effects of, x, 239;

sensation of, xi, 128

Wet Steam, v, 140

Whalebone, xii, 298

Whales, xii, 297-9;

sawfish and, 149;

squids and, 80

Whale's Food, xii, 19

Whaling Industry, aerial patrol in, i, 48

Wheat, ancestral home, xiii, 182, 221;

economic importance, i, 263, xiii, 208;

food value, viii, 364, x, 259, 261, 262, 267, 278, 279;

fruit for seed dispersal, xiii, 56;

germination of seeds, ix, 16-17, xiii, 211;

history and forms, 210-11;

in grass family, 179;

Mediterranean source, xiv, 382;

phosphate requirements, 67;

protein in, xiii, 95;

rust, 13;

snow and, i, 253;

stalk stiffening, viii, 337;

starch made from, 243;

time required to produce, v, 249;

vitamines in hulls, ix, 35, 36

(see also Winter Wheat)

Wheatstone Bridge, iv, 301, vi, 80

Wheel and Axle, v, 31-3;

action of, like lever, iv, 89

Wheel Lock, xv, 217

Wheeled Vehicles, use on farms, v, 215

Wheels, centrifugal force of, iv, 71;

discovery and development of, xv, 241-3;

evolution of, v, 16-17, 205;

form of lever, 21, 28;

friction, 204;

friction-saving by, 205-6;

large and small, 206;

not found in nature, 16, 215;

tendency to turn on center of gravity, 150;

in transportation, 214-15

Whelks, xii, 72

Whippoorwills, family of, xii, 267;

feathers about mouth, 244

Whirlwinds, dust, i, 60

Whiskey, making of, viii, 250

Whispering Galleries, iv, 239

Whistles, policeman's, iv, 220;

siren, 205

Whistling, impossible in caissons, iv, 32

White (color), reflection of light by, x, 309

White, Andrew D., on comets, ii, 84

White, Charles, x, 92

White, D., quoted, iii, 202, 343

White, I. C., anticlinal theory, iii, 352

White, Maunsel, v, 55, 383

White, Orlando E., xiii, 221

White Ants, xii, 110

White-blood, metabolism in, x, 272

"White Coal," v, 76, 174

White Corpuscles, ix, 182 (fig.), 184-8;

germ destruction by, 185-7, x, 197, 209-10;

passage through capillary walls, ix, 194

Whiteface, Mount, spring on, iii, 117

Whitefish, xii, 154, 159

White Flies, xii, 112

White Flour, vitamines absent in, x, 267, ix, 35

Whitehead Torpedo, v, 380

White Heat, temperature of, iv, 361

White Lead, viii, 162, 265

White Light, iv, 364;

composition, Colors, i, 165, iv, 357-9, 366-7, vi, 282, viii, 301, ix,

115, 3579, xvi, 119;

hands and face in, iv, 364-5

White Mts., Arctic species in, xiv, 377;

club mosses of, xiii, 305;

in Mesozoic Era, iii, 232

White Pine, in northern forests, xiv, 372;

region of, xiii, 368

White Plague, x, 290, 294

White Race, xv, 32;

beards in, 38;

brain weight, 41;

characteristics indefinite, 35-6;

disease immunity and susceptibility, 48, 49-50;

eyes, color of, 37;

facial angle in, 45;

hair, color and form of, 37, 38;

in tropics, i, 327, xiv, 344, 356-7, xv, 49-50;

jaw angle of, 44;

language relationships, 161-3;

light and dark divisions, 37;

measles in, 48;

nose index and nostril shapes, 45, 46;

savages' ideas of, 334;

separate origin theory, 70;

skull index in, 42;

skull capacity, 41

White Rainbows, i, 176, 384

White Rats, protein experiments on, ix, 287-8, 288

White Swelling, x, 78

"White Way" Lighting, vi, 279, vii, 339-40

White Whales, xii, 297

Whitman, Walt, "Song of Myself," xi, 336

Whitney, Eli, v, 269;

cotton gin, 269-71, 376, xiii, 237-8;

milling machine, v, 47, 378;

standard muskets, 49-50

Whitney, Mount, observatories on, ii, 144, 149

Whitney, Professor, on emphasis, xv, 144;

on language changes, 157

Whittlesey, Lake, iii, 148

Whole Wheat Bread, vitamines in, x, 267

Whooping Cough, consumption from, x, 292;

germ of, 216

Wickam, H. A., "botanical specimens" of, xiii, 247

Widal Reaction, x, 216

Wilberforce Spring, iv, 83-5

Wilcox & Gibbs Machine, v, 285

Wild Arum, fertilization, xiii, 153

Wild Asses, xii, 308

Wild Boar, xii, 310;

in Cro-Magnon paintings, xv, 114

Wildcats, xii, 356

Wild Dogs, xii, 345

Wild Ducks, seed dispersal by, xiii, 340-1

Wilderness of Judæa, xiv, 121

Wild Horse, xii, 306-7

Wild Mustard, origin in U.S., xiii, 353-4

Wild Ox, xii, 330-1

Willets, xii, 262

Will or Volition, xi, 259-67;

hypnosis and, 317, 318;

motor character, 61;

source of energy of, 33

William the Conqueror, at Salerno, x, 36, 37

Willamette River, navigability of, xiv, 195

Williams, Prof. Samuel, ii, 211;

quoted, i, 201

Williams, Wells, on Chinese astronomy, ii, 21

Williamson, chemical work, xvi, 133-4, 162, 165

Willis, Thomas, xvi, 108

Will-o'-the-Wisp, i, 346-9

Willow Trees, antiquity of species, xiii, 324-5;

family, 191;

fertilization, 122;

origin and product, 244;

petals absent, 190;

seed dispersal, 343;

sexes in, 47, 191;

sprouting of, 166

Willughby, xvi, 126

Wilson, A. B., sewing machine, v, 284-5, 379

Wilson, T. L., xvi, 190-1

Wimhurst Influence Machine, vi, 301

Winch, iv, 90-1

Winchell, A. N., i, 55

Winchester, James, quoted, i, 360

Wincing, origin, xi, 133

Wind, Winds, cause and general system, i, 124-9, xiv, 347-51;

climate determined by, 345-7;

complex structure, i, 292-8;

defined, x, 384;

direction, how observed, 82;

drying power, 77;

due to sun, v, 177, xiv, 32;

dust-carrying by, i, 52-5, iii, 71, 73-5, xiv, 77, 327;

eddies and updrafts, i, 53;

force measurement, 83-4, 294-6;

force in relation to isobars and altitudes, i, 126;

geological work, iii, 71-5;

gusts, i, 295;

human control, i, 332, 333;

in aeronautics, 284-6, 289-300;

lifting effort on kites, iv, 76 (fig.);

lightning and, i, 148;

local names, 132;

ocean, 271-6;

ocean currents caused by, xiv, 303;

plant fertilization by, xiii, 118, 123, 148-9;

power to blow objects aloft, i, 356;

pressure areas and, i, 124-6, 127-9, 134-5, 218, xiv, 349-50;

pressure due to inertia, v, 234;

projectiles and, i, 312-13;

rainfall and, 111;

rock destruction by, iii, 72-3, xiv, 41, 45, 62, 77, 233;

sailing against, iv, 77 (fig.), v, 182, 186-8;

seed dispersal by, xiii, 58-9, 156, 340, 343-6;

soils deposited by, iii, 73-4, xiv, 71-5;

sound and, i, 187, iv, 210-11;

superstitions, i, 334-5;

topography and, 292, 294 (fig.), 296-7;

types, 130-9;

use of power, 37-8, v, 75, 111, 173, 182;

velocity and force, i, 83, 84, 137, 138;

vertical, 293;

waves caused by, xiv, 299;

weather and, i, 237-8, xiv, 349-50;

worship of, by Polynesians, xv, 342

Wind Aloft, i, 384

Wind Aloft Maps, i, 230, 231, 233

Wind Charts, i, 206, 271-3

Wind Gaps, iii, 39, 38 (fig.), xiv, 58, 98, 169

Wind Instruments, iv, 231;

development of, xv, 316-17

Windmills, v, 75, 111;

modern use, i, 37-8

Windpipe, cartilage in, ix, 57;

connections and parts, 255

Wind Rose, i, 273-4, 384

Wine, alcohol in, how measured, iv, 113;

flavors of, viii, 248-9;

pasteurization of, x, 139-40;

religious uses, primitive, xv, 352

Wine Making, viii, 248-9;

Pasteur's discoveries, x, 138, 139-40

Wine Palm, xiii, 53

Winged Fruit and Seed, xiii, 58, 345-6

Wings, of birds, xii, 247

Wings, of flowers, xiii, 47-8

Wing Shells, xii, 73-4

Winkles (shellfish), xii, 72

Winnepeg, Lake, iii, 144

Winter, effects on life, xi, 51;

human efficiency in, i, 323;

keeping warm in, ix, 309, 312;

land and sea winds in, xiv, 346;

mild and severe, how determined, 350;

"old fashioned," i, 200-2;

thunderstorms, danger of, 156

Winter-Days, temperature, i, 205, 384

Wintergreen, origin, xiii, 255

Wintergreen Plants, xiii, 202

Winter Provender, of rodents, xii, 292-3

Winter Wheat, best time to plant, i, 256;

snow and, 253

Wireless Communication, vii, 258-98;

condensers in, vi, 303, 304;

dependent on simultaneous reactance, 171;

hot-wire ammeters in, vii, 163, 164

(see also Radio)

Wireless Control, of aeroplanes and ships, vii, 283-4

Wireless Signals, in aeronautics, i, 291, 292, 302

Wireless Telegraphy, iv, 313-16;

alternating currents in, vi, 168;

conditions of transmission, vii, 272-3;

detectors, 268, xvi, 191-2;

history, 191;

induction coils in, iv, 305, 313, 314;

resonance in, 226;

strays or static, i, 162-3;

theory for amateurs, vii, 285-98;

vacuum tubes in, vi, 125, vii, 276-80;

weather reporting by, i, 257, 269, 280-2, 315;

in World War, vii, 283

(see also Wireless Communication)

Wireless Telephony, iv, 315-16;

aeronautical uses, i, 44-5, 302;

alternating currents in, vi, 163;

current conversion, 339-41;

development of, vii, 280-3;

distress signals, 284;

theory for amateurs, 285-98;

vacuum tubes in, vi, 125, 339-41, vii, 276, 278, 279, 280;

weather reporting by, i, 257;

in World War, vii, 282-3

(see also Wireless Communication)

Wires, current-capacity table, vii, 58;

leakage, 10-11;

measure (circular mils), iv, 282-3;

measure (mils), vi, 77, vii, 373;

resistance of, iv, 281, 282-3, vi, 79;

sizes and kinds in transmission, vii, 20-4;

standard tables, (copper), 378-81;

types of insulation, 58

Wireworms, xii, 124

Wiring, interior, vii, 51-72;

exterior (see Overhead, Underground Transmission)

Wishbone, of birds, xii, 247

Wisby, in Hanseatic League, xiv, 282

Wisconsin, drainage studies in, xiv, 131;

drumlins of, iii, 69, xiv, 60;

Ice Age in, iii, 239;

lakes of, xiv, 200;

terminal moraines in, 59

Wise, John, rip panel inventor, v, 224

Wiseman, Richard, x, 78

Wishes, dreams from, xi, 293, 299-300, 301-2;

suppression of, 140-2, 257

Wistar, Casper, x, 116

Wit, psychology of, xi, 350-7

Witchcraft, former theories of, x, 357, 360

Witches, colonial ordeals for, xv, 373

Witchhazel, origin, xiii, 255

Witch-Hazel Plant, seed dispersal, xiii, 339

Witnesses, influence of forms of questions, xi, 308-10;

untrustworthiness, 103, 168

Woevre, France, xiv, 91

Wöhler, Friedrich, x, 126

Wolf, astronomer, ii, 134

Wolff, Caspar F., xvi, 118

Wolf-Rayet Stars, ii, 116

Wollaston, William Hyde, xvi, 122, 162;

spectrum studies, ii, 111, 112

Wolverine, xii, 348-9

Wolves, xii, 340-2;

dogs and, 344;

ears of, 346;

in Great Britain, xiv, 273;

Tasmanian, xii, 277

Wombat, xii, 278

Women, basal metabolism of, x, 271;

bearing of pain by, ix, 87;

brain weight in, xv, 39;

color-blindness in, ix, 116, 340-1;

dress of, x, 309;

ear-rings of, xv, 259;

food requirements, viii, 367;

heart rate in, x, 334;

height of, xv, 38;

modesty and immodesty in dress, 254-5;

painting of, 256;

skull capacity, 40;

susceptibility to temperature changes, x, 240;

voice tones of, ix, 99

Wonder, in various sentiments, xi, 146, 147

Wood, chemical material of, viii, 44;

decay of, xiii, 71;

distillation for wood alcohol, viii, 214;

electrical conductivity, iv, 259;

flame of burning, viii, 57;

heat conductivity, iv, 176, 177;

percentage of carbon in, viii, 44;

petrified, iii, 15-16;

sound velocity in, iv, 201;

storage appliance of plants, xiii, 96;

use as food, ix, 24

(see also Heartwood, Sap wood)

Wood, Henry Wise, v, 383

Wood Alcohol, viii, 214;

flame of, 60;

used as denaturant, 250

Wood Ashes, lye from, viii, 276;

potash in, 279, 343, 344, xiv, 67

Woodchucks, xii, 295

Woodcocks, xii, 263

Wood Lice, xii, 82

Woodpeckers, xii, 267;

mating of, xv, 276-7;

toes of, xii, 265;

use of tools, v, 11

Wood Pulp, in paper making, v, 290, 292-5, 380

Wood Sorrels, leaves, xiii, 88-9, 113

Woodward, Dr. Robert S., ii, 147, xvi, 126

Woody Tissue, composition, xiv, 65

Woof, of woven goods, v, 278, xv, 244

Wool, as clothing material, x, 307, 308, 309, ix, 311;

chemical properties and manufacture, viii, 256;

dyes of, 259;

electrification of, iv, 257, 258, 259;

humidity effects in manufacture, i, 78;

removal of cotton from, viii, 255;

warmth, to what due, iv, 178

Wool Grass, xiii, 182 (fig.)

Wool-pack Clouds, i, 101-2, 384

Woolwich Observatory, founding, xvi, 127

Woolworth Building, elevator system, v, 134-5;

height of tower, 79;

flood lighting, vi, 283

Wordsworth, paradox of, xi, 247

Words, changes in meanings of, xv, 157;

double meanings, 158-9;

inadequacy in feelings, 143;

origin of various, 153-4, 157, 161

Work (labor), conditions of, importance, xi, 361-2;

daily amount in calories, ix, 297;

daily amount in foot-tons, x, 305;

effect of distractions, xi, 277;

fatigue and capacity for, x, 246, 247;

fatigue from new, ix, 81;

fatigue in pleasant and unpleasant, xi, 274-6, 277-8;

food energy consumed by, viii, 367;

planning of, xi, 377-8;

rest periods and efficiency, 363

(see also Vocations)

Work (mechanics), iv, 37, 38;

accomplished by inequalities, viii, 168;

energy and, iv, 37-40, 78-88;

heat relations to, 189-91, 193;

measurement and units, 78, 79-80, 189-90, vi, 81-2, 84;

rate of, iv, 80

(see Power)

Workers, food requirements and energy of, viii, 367;

instruction of beginners, xi, 363-5;

interest of, 376;

jobs and, 358-61;

tool adjustment to, 362

World War, aeronautical development, i, 40-1, 284, 285, iv, 10, 107;

aeronautical weather services, i, 304-5;

aeroplane accidents, x, 246;

aeroplane machine guns, v, 107;

aeroplane mapping, i, 45;

aeroplanes, luminous glories seen, 185;

aftermath of, x, 188-9;

artillery phenomena, i, 193-4;

artillery vs. armor, v, 368;

big guns, v, 368-71;

bombardment of Antwerp, i, 191;

cannonading heard at distances, 188;

care of disabled, (U. S.), x, 188-91;

chemical warfare, viii, 262-4, x, 186-8;

chemical warfare service device, viii, 283;

chemistry in, xvi, 159;

commerce destruction in, xiv, 306;

cultural setback by, xv, 30;

dried foods in, viii, 371;

dye industry in, 253;

electricity in, vi, 10;

flood lighting, 283;

flying machines, v, 233;

French forests in, xiv, 239;

gas masks, viii, 48;

German aircraft at beginning, x, 40;

German lack of jute bags, xiii, 241;

German plans on two fronts, xiv, 91-2;

German torpedoes, v, 374;

Germans called Huns, xi, 22;

Germany's nitrate needs, xiv, 66;

helmets and armor in, xv, 221;

hysterical phenomena in, x, 363;

ignorance of southern mountaineers in, xv, 131;

influenza pandemic, x, 294-5;

Italy in, xiv, 244-5, 252-3, Italy in, xv, 138;

invasion of France and Belgium, topographical considerations, xiv,

88-93;

inventions, v, 360, 384;

jaundice in trenches, x, 201;

Liberty engines, v, 53-4;

machine guns, 363-8;

Marne retreat incidents, xi, 286-7;

medical achievements of, x, 176-91, 384;

meteorology in, i, 290-1, 307-15;

mirages in Mesopotamia, 173;

motors used, direct current, vi, 239;

nitrogen needs and production, i, 34, 36, viii, 246, xiv, 66;

pilot balloons, i, 22;

potash dearth and supplies, viii, 143-4, 279, 344, xiv, 67;

projectiles and shells, v, 372;

rain in battles, i, 338;

Russian bison destroyed in, xii, 329;

Russian elk destruction in, 318;

scientific progress in, iv, 10-11, xvi, 9, 195;

scurvy in, x, 265;

searchlights on fleets, iv, 352;

sleeping sickness epidemic, x, 301;

smoke screens, viii, 87;

sound-ranging, i, 313, iv, 201-2;

sphagnum use in, xiii, 160-1;

stereograms in, xi, 180-1;

submarines, v, 198, 200-1;

submarine spotting, i, 47;

sulphuric acid importance, viii, 78-9, 80;

surgery in, x, 181-3, 381-2;

Switzerland in, xiv, 243-4;

tanks, v, 218;

tetanus infection in, x, 299;

trench fever in, 202;

tuberculosis in France, 175;

typhoid fever in, 217, 288;

vitamine foods lacking in certain countries, 260;

volcanic power in Italy, v, 179-80;

well-poisoning in, xv, 228;

wheat in rationing, viii, 364;

wireless operations, vii, 282-3;

"Who won it?," v, 300;

wood as food in, ix, 24;

Zeppelins and captive balloons, v, 227

World Weather Bureau, i, 221

Worm Gears, v, 37 (fig.), 88

Worms, xii, 44-5, 50-6;

classification, iii, 259;

earliest tracks, 263, 270;

power of distinguishing light, ix, 105;

regeneration in, xii, 170;

sea, 18, 23

Worms (disease), x, 200

Worry, feeling of, ix, 153-4, 167;

hardened arteries from, x, 335;

indigestion from, ix, 165, 167, 240-1

Wound-Rotor Induction Motor, vi, 245, 248, 256

Wounds, antiseptic treatment of, x, 145-6, xvi, 182-3;

Carrel-Dakin treatment of infected, x, 181-3, 382;

former treatment, 40, 43, 54-5, 59, 78-9;

healing of modern surgical, 123;

painlessness to soldiers, xi, 119, 120;

Paré's treatment of, 55, xvi, 108;

radiation treatment of septic, x, 384

Wound Suckers, x, 91, 105

Wove Paper, v, 296

Woven Fabrics, threads of, v, 276, 278

Wright, Sir Almroth, x, 218

Wright, Orville and Wilbur, v, 231-2, 237-8, 383-4;

early flights, i, 300

Wright, Thomas, ii, 350, 367, 380

Wright Machines, v, 232, 236, 237-8

Wrigley Triplets Sign, N. Y., vii, 340-1

Wrist, bones of, ix, 67, 68 (fig.);

pulse in, 211

Writing, development of, xv, 164-79, 325, xvi, 60;

by telegraph, vi, 98;

remarks on art of, ii, 10;

reflex actions in, ix, 157

Written Language, association principle in, ix, 152;

importance to man, 153

Wrong, original meaning, xi, 190

Wrought Iron, v, 317, viii, 158-9

Wyberd, on corona, ii, 221

Wye Connections, vi, 209, 318, 325

Wyoming, badlands of, xiv, 82;

cattle ranges, 222-3;

dike systems, 106-7;

marine fossils in, iii, 82;

volcanic fields, xiv, 318

Xanthine, viii, 230

Xenon, in atmosphere, i, 11, 12;

symbol and atomic weight, viii, 383

Xenophanes, on fossils, iii, 14

Xiphosura, xii, 81

X-ray Analysis, of crystals, viii, 313

X-ray Photography, iv, 55, 320-1;

uses of, vii, 253-4, x, 222, 372-4

X-rays, iv, 317-21, vii, 249-57, x, 184-6, 254, 383;

discovery of, iv, 55, 317, x, 183-4, xvi, 192-3;

fluorescence produced by, iv, 320, 378-9;

invisibility, 319, 378;

transmitted through æther, vi, 119, 269;

vibration frequency, iv, 379, vii, 260

X-ray Spectra, viii, 183, 309

X-ray Tube, iv, 319, vii, 251-2;

operated by induction coils, 244;

static generators for, 245

Xylene, from coal tar, viii, 253

Xylols, viii, 235

Xylophone, iv, 224

Yaks, xii, 330

Yakutat Bay, Alaska, xiv, 334-5;

faulting in, 114, 334-5

Yakutsk, Siberia, i, 210

Yale College, founding, xvi, 127

Yampa River, xiv, 166, 168, 175

Yams, origin and antiquity, xiii, 224;

water, of Madagascar, 89-90

Yapocks, xii, 276

Yard, unit of length, iv, 45, 69;

value in meters, 46, 70

Yarn, grading of, v, 272;

making and weaving of, 268, 272-82

Yawning, as fear effect, xi, 132

Yaws, racial susceptibility to, xv, 50, 51

Y-connections (see Wye)

Year, beginning of, in ancient Egypt, ii, 26;

in Cæsar's calendar, xvi, 98;

length fixed by Hipparchus, 11, 32;

length in ancient Egypt, xvi, 70;

measurement of, iv, 15;

without a Summer, i, 359-61, 361-2

"Yearning of Bowels," xi, 64, 131, 160

Yeast, cells of, xvi, 142-3;

disease-producing, x, 196;

fermentation in dough, ix, 248;

fermentation by pure and other cultures, x, 138;

leavening powers of, viii, 50;

non-flowering plant, xiii, 13, 14, 43;

origin of power, 71;

reproduction, 164;

vitamines in, ix, 36, x, 260, 261

Yellow, complementary color of, iv, 367;

photographic action of,366;

soothing effects, vi, 274;

wave length of, iv, 359, 365

Yellow Days, cause, i, 57

Yellow Fever, x, 159-63;

campaign against, 162, 172-3, xiv, 356-7;

discovery of cause, x, 160-3, 173, 200;

immunity to, 207, xiv, 357;

virus of, x, 161, 200

Yellow Race, xv, 32;

brain and skull capacity in, 41;

diseases of, 51;

facial angle in, 45;

jaw angle of, 44;

nose index and nostril shape, 46;

peoples of, 37;

separate origin theory, 70;

skull index, 42

Yellowstone Lake, xiv, 180;

altitude, 205

Yellowstone National Park, freaks of nature in, vii, 202;

geysers in, iii, 129;

Hayden Relief model, xiv, 10;

hot springs, 143;

jointed rocks, 129;

petrified forests, iii, 126-7;

travertine terraces, xiv, 146;

uncooled lava masses, 313-14

Yellowstone River, canyon of (see Grand Canyon of the Yellowstone);

falls of, iii, 48-9;

geological history, xiv, 180

Yerkes Telescope, ii, 98, 202;

magnification by, iv, 346

Yersin, bubonic plague work, x, 164, 165;

pupil of Pasteur, 143

Yew Tree, ancestors of, xiii, 317;

a conifer, 174;

in landscaping, 270;

of Tasmania, 30

Yorkshire Coast, recession of, xiv, 47, 301

Yosemite Falls, iii, 47-8, 65

Yosemite Valley, air currents, i, 296, 297;

formation, iii, 44, 64-6, 225;

granite walls, 112, 214;

impressiveness, vii, 202

Young, Prof., astronomical work, ii, 120, 128, 142, 181, 183, 201,

222-3, 307

Young, Thomas, x, 96-7, xvi, 174

Young's Modulus, iv, 157, 158

Yperman, Jean, x, 41

Ypres, chemical warfare at, x, 186

Yssel River, xiv, 45

Ytterbium, symbol and atomic weight, viii, 383

Yttrium, symbol and atomic weight, viii, 383

Yucatan, chocolate cultivation, xiii, 234;

sisal production, 240-1

Yucca Plant, pollination of, xvi, 152-3

Yukon River, use of, xiv, 191

Zambezi, crocodiles of, xii, 200

Zambezi River, gorge and falls of, xiv, 131-2,

(see also Victoria Falls);

lava field of, 317;

varied course, 155

Zanzibar, clove production, xiii, 262, 263

Zebras, xii, 307-8

Zeno, Greek philosopher, xvi, 84-5

Zeolites, in softening water, viii, 324

Zeppelin, Friedrich von, v, 225-6, 228, 382

Zeppelins, v, 225-6, 228-9, 382;

development by Germany, i, 40;

in World War, 310

Zero, invention of, xvi, 184

Ziczac, Egyptian, xii, 263

Zinc, affinity intensity, viii, 128;

atomic weight and symbol, 383;

extraction from ores, 270, 271;

in electric cells, vi, 59, 61, viii, 167;

in heavy metal group, 126-7, 154;

melting point and requirements, iv, 162, viii, 384;

occurrence and production, iii, 363-4, viii, 129, 198;

specific gravity, 384;

test for, 287, 289;

uses, iii, 363, viii, 155-6;

used in hydrogen preparation, 32-3

Zinc Carbonate, viii, 130

Zinc Sulphate, viii, 96

Zircon, iii, 341;

axis ratio, 317

Zirconium, symbol and atomic weight, viii, 383

Zodiac, ii, 254

Zodiacon, i, 192

Zoetrope, v, 329

Zone of Flowage, iii, 84

Zone of Fracture, iii, 84;

action of rocks in, 86

Zones, Climatic, earliest distinction, iii, 220;

not marked in oldest times, 173, 178, 184, 202

Zones of Silence, i, 189-92

Zoögonidia, movements, xvi, 166

Zooids, xii, 34

ZOÖLOGY, Volume xii

Zoölogy, binomial nomenclature in, x, 84;

daily interest, xvi, 15-16, 22, 25-6;

defined, xvi, 36;

history of development, 116, 126, 140-8

Zoöpraxiscope, v, 330

Zorilla, xii, 348

Zuider Zee, formation of present, xiv, 45-6

Zulus, ideas of future life, xv, 333;

musical instruments of, 317;

polygamy among, 288

Zuni Indians, pottery-making by, xv, 250 (fig.)

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P. F. Collier & Son Company

416 West 13th Street

New York, N. Y.

Gentlemen: Kindly send me Revision Service

Sheets on Popular Science Library, for the

year 1931. I subscribed for Popular Science

Library in the month of____________________

19____, and my address then was--

___________________________________________

___________________________________________

You may send the above requested Revision

Sheets to me at the following address:

_Name_ ________________________________

_Address_ _____________________________

_______________________________________

_______________________________________

+Important+ _Mail this to Publisher between

March 1, 1932 and May 1, 1932_

_Request Form--1932_

Revision Service

POPULAR SCIENCE LIBRARY

_Date____________________

P. F. Collier & Son Company

416 West 13th Street

New York, N. Y.

Gentlemen: Kindly send me Revision Service

Sheets on Popular Science Library, for the

year 1932. I subscribed for Popular Science

Library in the month of____________________

19____, and my address then was--

___________________________________________

___________________________________________

You may send the above requested Revision

Sheets to me at the following address:

_Name_ ________________________________

_Address_ _____________________________

_______________________________________

_______________________________________

+Important+ _Mail this to Publisher between

March 1, 1933 and May 1, 1933_

TRANSCRIBER'S NOTES

Silently corrected simple spelling, grammar, and typographical

errors.

Retained anachronistic and non-standard spellings as printed.

Enclosed italics font in _underscores_.

Enclosed signatures or cursive font in ~tildes~.

Enclosed italics and underlined font in +plus signs+.