When the forty weeks of San Francisco’s World’s Fair are over, 40,000,000 kilowatt hours of electricity will have been consumed in producing the night picture, painted in light, on Treasure Island. Three 9,000-foot submarine cables, more than 35,000 miles of cables, provide the “juice” required for the amazing color effects. A budget of $1,500,000 has been given to the illuminating engineers, directed by A.F. Dickerson, expert of the General Electric Co., unparalleled opportunity to carry out the most comprehensive and unified program of exterior lighting ever attempted.

Except in the Gayway, where bright lights are the stimulant to fun and frolic, indirect lighting prevails. Roadways and walks are lighted with gigantic lanterns. Varying in height to as much as 86 feet, cylindrical lanterns, five feet in diameter, are made of heavy canvas treated with glyptol, giving a parchment glow. These “shades” are hung over a framework of stout steel shaft and steel hoops. One hundred 60-watt and 100 40-watt lamps are screwed into the central shaft and when lighted consume 10 kilowatts of current. Each light standard weighs approximately 2400 pounds and requires as much as 180 square yards of fabric. Other lanterns, from 30 to 50 feet high, are patterned after Siamese ceremonial umbrellas, lyres, and other designs.

Great 70-foot-high walls of stucco, flecked with iridescent vermiculite (flakes of super-heated mica), have large circles of colored light to form contrasts against the ivory background, and floodlighted trees cast spidery silhouettes. Hidden in troughs, tucked in branches, clustered in tree baskets, almost buried under shrubs, are 10,000 colored floodlights, including 2400 pink, blue, gold, and green gas-filled fluorescent tubes, 130 searchlights and 300 ultra-violet mercury or “black light” lamps to produce the startling effect of color masses and patterns. Light is graded in intensity from the base of buildings to the top to maintain the depths of arcades and accentuate architectural set-backs.

“Black light” projected on invisible weather-resistant luminescent paints in niches, on murals, and sculptures, produces the startling “colored pictures” that stand out in an almost phosphorescent glow against adjacent colored walls. Primary colors are mixed together to obtain new colors. Pink fluorescent tubes crossed by blue floodlights produce mauve, Trees lighted green stand out against the background of pale tinted walls. Fountains are lighted with their own colors. In the Court of Pacifica, a thyratrone behind the scintillating Persian Prayer Curtain produces a rotation of colors varying from dark blue to pale apricot.

Switches and buttons on an electrical control board in each building are set permanently wherever the color scheme is static. Fountain lights are controlled from the bases of nearby statues. Controlling all these is a set of four switches on a master switchboard which can be turned on at any given hour.

Overhead is a scintillator of light covering Treasure Island just a few feet above the 400-foot Tower of the Sun. Twenty-four gigantic searchlights, 36 inches wide, in eight different colors, are mounted on the north side of Yerba Buena Island. These army-sized lights, when turned on for special occasions, are manned by a crew of 24 and generate 1,440,000,000 candlepower of light visible for 100 miles.

In: Official Guide Book
Golden Gate International Exposition