Light, iv, 322-34; aberration of (see Aberration of Light); absorption in space, ii, 160, 354-5; absorption of, by objects, iv, 364; actinic effects, vii, 250; artificial, applications of, iv, 50-1; artificial, colors, of, ix, 115; bacteria destroyed by, viii, 332; body regulation to, x, 250; chemical action of, viii, 171-2; chromatic aberration, ii, 99-100; corpuscular theory of, iv, 47, 50, xvi, 136; decomposition, ii, 99, 111, 112, iv, 357-9 (see also Spectrum, Spectroscope); deflection of, 330, 374; deflection by sun, ii, 81-2; diffraction, i, 183, iv, 326; effects of objects on, 323-4; effects on organisms and man, x, 253-4; Einstein theory, ii, 80-2; electrical production, inefficiency, vi, 268; electromagnetic theory of, iv, 54, vi, 25, vii, 371, xvi, 137-8; eye and, vi, 270-2, xi, 86, 95-6; eye regulation to, x, 254; from sun, importance of, ix, 25-6; "gentleman" of physics, iv, 50; glowing effects on minerals, vii, 254; injury from excessive, 153; intensity unit, iv, 351-2; interference of, 376-8; instinct of seeking, xi, 52-3; invisibility, iv, 333-4; machines responding to, v, 331-2, 332-3; measurement of illumination of, iv, 350-2; measurement of intensity, viii, 374; monochromatic, iv, 364, 365; of electric lamps, vi, 268; of firefly, 268; of glowworms, xvi, 144; of moon, ii, 200; of stars, 296; of sun, 168-9; penetration of ocean by, xii, 22; perception limits, iv, 360-1; perception of, in animals, ix, 105; physiological sensation, vii, 249; polarization, iii, 319-20, iv, 353-6; polarization, discovery, xvi, 119; production by various kinds of rays, iv, 378-80; quantity unit, 352; radiant energy, 322, ix, 114; rays of, iv, 323; reflection and refraction (see Reflection and Refraction); seeing by, iv, 322-3, 324-9; shadows cast by, 332-3; theory of, present state, 50; transformed to musical sounds, v, 332-5; transmitted by ether, vi, 119, 120, 269, vii, 259; traveling of, in straight lines, iv, 330; velocity, 323; velocity constancy, xvi, 196; velocity in different media, iv, 327; velocity, methods of obtaining, ii, 59-60, 91, 167; vibrations and colors of, ix, 115; wave theory, iv, 47, 353, vi, 118-19, 269, xvi, 136-8; wave theory discovery, 119; white (see White Light); wind effects on, iv, 211 (see also Light Waves, Sunlight) Light-headedness, production of, ix, 266-7 Lighthouses, strength of, xiv, 300-1 Lighting, art of, modern advances in, iv, 50-1; direct, xi, 277, 373; emotional effects, vi, 273; factory, xi, 361; flood, vi, 283; modern gas, viii, 60; proper and improper, vi, 273-5; unit of intensity, vii, 368 (see also Electric Lighting, Lighting Systems)