Measures for Progress: A History of the National Bureau of Standards

186 THE WAR YEARS (1917-19)
make it impermeable to wind and moisture, and improve the flight charac-
teristics of the plane. In the turmoil of designing an American plane and
engine, the subject of dopes was somehow overlooked, and when late in 1917
the first acetate orders went out, its raw materials had already been com-
mandeered by other Government agencies.
With acetate gone, nitrate (guncotton) dopes were used for a time,
until Eastman Kodak provided a small supply of acetate from cuttings and
scraps of nonflammable motion picture film. (Why the airplane program
was left with cuttings and scraps is not recorded. True, the research came
late in the war and remained in the experimental stage. Possibly, too, the
supply oi motion picture film was limited and was needed by the services
and for the spate of propaganda films made for domestic consumption.)
Meanwhile, the Bureau was testing scores of new solutions proposed as
dope substitutes, establishing specifications for those that seemed to have
some value, and making studies of their application to fabrics. Only a few
"fire-proofed" nitrate dopes of the many so-called fire-resistant solutions sub-
mitted proved acceptable, and then only when the fabric itself was also fire-
proofed.66
American scientists never wholly overcame the problem—nor did
anyone else. The need for fireproofing was real even though in aerial
combat, tracer and incendiary bullets rarely ignited the fabric of planes.
It was the engine of World War I planes that was most susceptible to fire.
Occasionally a pilot was able to execute sideslipping maneuvers and keep
the engine flames from igniting the fabric. Where that failed, the plane was
consumed as it fell.
OPTICAL GLASS AND OPTICAL INSTRUMENTS
Although Dr. S'tratton never actively took part in the optical research
at the Bureau, his work with Michelson on light at the University of Chicago
was the impulse for his years of personal direction of the optical division.67
The men he brought in—Bates in polarimetry, Coblentz in radiometry
Priest in colorimetry, Peters in interferometry, Meggers in spectroscopy—
were topnotch, and he zealously followed with them every development in
the field of optics both here and abroad. Yet as numerous as were the
military applications of optics, it was a crisis in supply that shaped the
principal wartime effort in optics at the Bureau.
°° "War Work," p. 56.
Explaining the interferorneter and its use in standardizing gage blocks to a congressional
committee on one occasion, Stratton said that "interferometry is the field of measurement
in which I am personally interested, and in which I was engaged when called to take
charge of the bureau" (Hearings * * * 1924, Nov. 16, 1922, p. 191).