Part 36

Egypt: 31; sacredness of light in ancient, 39; 153, 195

Electric filament: 81, 127 et seq.: approximate value of, lamps (table), 138

Electric pile: construction of, 111; 127

Electricity: 13, 22; as a light-source, 57; for home-lighting, 62, 84; 87, 89; ignition of gas by, 102; lighting by, 109 et seq.

Electromagnetic waves, 68, 86, 87

Electromagnets, 114, 116

Electrodes, 113, 114, 115 et seq.; life of, 122

Elizabeth, Queen, 274

England: 32; petroleum discovered in, 56; gas-lighting in, 63 et seq.; 166, 251, 274

Erbia, 85

Esquimaux: 18; use of artificial light by, 31

Ethylene, 106

Factories: 13; artificial light in, 239 et seq.

Faraday, 113

Filaments, carbon, 129 et seq.

Finsen: 273, 274, 275; on stimulating action of artificial light, 277; 279, 280

Fire: importance of, to man, 5 et seq.; man's dependence upon, 15; mythical origin of, 16; making, 17 et seq.; production of, in the stone age, 18; in early civilization, 19; ancient worship of, 29, 299

Fireflies: 24, 81, 96, 148, 149, 150

"First Men in the Moon, The," H. G. Wells, cited, 148

Fish: artificial light as bait for, 249

Flame-arcs, 120, 121, 122, 187

Flames: 86, 88, 89; open, 233, 234 et seq.

Flint, 33

Fool's gold, 18

Fort Wagner, 185

France: lamps in, 55; early gas-light in, 72

Franchot, invention of moderator lamps by, 55

Frankland, 77