Development of the Incandescent Electric Lamp."
"Color and Its Applications," and "Light and Shade and Their
Applications," are two books by Luckiesh which deal with lighting from
unique points of view. "The Language of Color," by Luckiesh, aims to
present what is definitely known regarding the expressiveness and
impressiveness of color. W. P. Gerhard has supplied a volume on "The
American Practice of Gaspiping and Gas Lighting in Buildings," and Leeds
and Butterfield one on "Acetylene." A recent book in French by V.
Trudelle treats "Lumiere Electrique et ses differentes Applications au
Theatre." Many books treat of photometry, power-plants, etc., but these
are omitted because they deal with phases of light which have not been
discussed in the present volume. "Light Energy," by Cleaves, is a large
volume devoted to light-therapy, germicidal action of radiant energy,
etc. References to individual articles will often be found in the
various indexes of publications.

THE END

INDEX

Aaron, 43

Accidents: 8;
street-lighting in relation to, 225 _et seq._;
percentage (table) of, due to improper lighting, 231

Acetylene: 62;
light-yield of, 106, 107, 170, 187, 191

Actinic rays: effect of, upon human organism, 275

Africa, public lighting in ancient, 31

Agni, god of fire, 40

Air-pump, 130

Air-raids, 225

Alaska, 18, 29

Alchemy, 20

Aleutians, 18

Alexandria, 43, 163

Allylene, 106

Aluminum, 108, 179, 180

Amiens, Treaty of, 69

Amylene, 106

Aniline dyes, 106

Animal: distinction between, and human being, 3; 15;
production of light, 24 _et seq._;
sources of light, 30, 31;
oils, 51

Antimony, 294

Antioch, 153

Arago, 114, 196

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,