City of Light: The Story of Fiber Optics

18 CITY OF LIGHT
the British exhibitions, and he returned to design fountains that stood outside
the main entrance, shown in figure 2-2.
As in Britain, changing filters colored the light electric arcs cast on the
waters. Flood lamps lit the fountains from above. Mirrors and lenses aimed
light up jets that spouted vertically, much like earlier fountains. However,
Bechmann designed nozzles for horizontal jets with lenses in their middle, so
the light emerged in the middle of a hollow cylinder of flowing water, shown
in figure 2-3. Viewers saw luminous water spout from the mouths of sculpted
dolphins, then descend in graceful parabolas to the pools beneath. 28 As in
Faust, the water seemed alive with light.
Colladon must have been delighted on his visit to Paris. Strictly speaking,
total internal reflection did not guide the light; it was trapped within a flowing
tube of water. The simpler scheme of shining light inside a water jet was
impractical with fast-flowing water and bright lights. However, the effect
looked the same to the audience, and that was good enough for anyone but
an optical purist. The fountains at the Universal Exposition were the most
spectacular yet. Paris recognized Colladon as the father of the illuminated
fountains, and Bechmann immortalized him in an article in Le Grande Encyclopedie.
29
Light Pipes in America
Luminous fountains eventually brightened nights at the 1894 World’s Fair
in Chicago, 30 but before then a resolutely practical American had more mundane
ideas for light guiding. A Yankee engineer named William Wheeler
wanted to illuminate homes by piping light from an electric arc in the basement.
It wasn’t a crazy idea in 1880 when he filed for a patent. People were
piping gas, heat, and water through buildings—why not light?
Wheeler had just finished an eventful few years. He was trained as an
engineer in the first class to attend what is now the University of Massachusetts,
graduating at 19 in 1871. He settled in his native Concord, Massachusetts,
and ran an engineering practice in Boston until his college mentor,
William Smith Clark, lured him to Japan to help organize an American-style
agricultural college on the northern island of Hokkaido. Clark became a Japanese
legend, and Wheeler served as college president while still in his twenties.
31 Wheeler came home full of ideas in 1880, and in the next few years
filed over a dozen patents, most on reflectors to concentrate light. In 1881,
after resuming his engineering practice, he founded the Wheeler Reflector
Company to manufacture the things.
The ambitious young engineer carefully plotted the logic of light-pipe illumination.
His patent 32 explains:
It is well understood that electric light may be produced through the use
of dynamo-electric machines cheaper than light from gas or any known
method by combustion. This requires, however, that the light be produced