THE STORY OF ARTIFICIAL SILK
phernalia of Medical Science, but the whole
of it does not atone for what we have lost
by the diminution of sunlight and fresh air.
We human beings are children of the Sun.
The sunlight that comes to us through
93,000,000 miles of space is our source of life.
Lt is filtered through 100 miles of atmosphere
and smoke and dust and cloud. It is not
pure when it reaches us, but it is the power
whereby we live.
It is an extraordinary fact that we knew
nothing about the composite nature of sun-
light until two centuries ago. Sir Isaac
Newton discovered it. He showed us for
the first time the marvel of the spectrum.
Then, in 1801, Ritter discovered the Ultra-
Violet rays—the invisible rays of shortest
wave-length. About 1850, Arnold Rickli, an
Austrian, started the first Sunlight Clinic at
Veldes, in Austria. He amazed the doctors
by his success in healing diseases.
In 187%, Dr. Downes and Dr. Blunt read
papers on the healing power of Ultra-Violet
rays before the Royal Society. In 18go,
Koch proved that the bacilli of tuberculosis
are killed by these rays. They are killed in
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