Part 32

Archbishop of Canterbury, 49

Archimedes, 19

Arc: lamps, 69, 89; electric, 111 et seq.; distinction between spark and, 112; Davy's notes on electric, 113; formation of, 115, 116; Staite and enclosed, 117, 118; principle of enclosed, 118, 119; types of, 120; flame-, 121, 122; luminous, 122; electric, 127; luminous efficiency of electric (table), 124; 160 et seq.; -lamp in lighthouses, 168 et seq.; magnetite-, 187; 261

Ardois system of signaling, 199

Argand, Ami: 52; inaugurates new era in artificial lighting, 53, 54; 63, 70, 76, 77, 78, 97, 167, 196

Argon, 137

Aristophanes, "The Clouds," 19

Art Museums, 9, 13, 322, 323

Asbestos, 170

Asia: public lighting in ancient, 31, 39

Automobiles, 238

Babylon, 39

Bacteria: effect of artificial light upon, 272 et seq.; 281, 282

Bailey, Prof. L. H., 250

Baltimore, 98

Bamboo: carbon filaments, 169

Bartholdi, 302, 303

Beacons. See Lighthouses.

Beck, 186

Beecher, 72

Beeswax, 35, 51

Benzene, 106

Bible, cited on importance of artificial light, 42-44

"Bluebird, The," Maeterlinck, 9

Blue-prints, 261

Bollman, 98

Bolton, von, 132, 133

Bombs, illuminating, 182 et seq.