Page 141 - James Rodger Fleming - Fixing the sky

precipitator—long used for removing smoke, dust, and fumes from industrial
gases—could be adapted to fog removal, but a medium-size airport installation
might require a huge elevated plate suspended some 32 feet above the ground,
with a potential difference between plate and ground of 6 million volts. Woe to
anyone or anything that short-circuited this apparatus!
n Thermal methods. It was well known at the time that supplying heat directly
to the atmosphere by burning fuel (discussed in detail later) was a simple, brute-
force method of dissipating fog. This technique, however, required an immense
amount of energy, since water has such a large latent heat of evaporation. The
apparatus (open fires, electric grids, blasts of air or steam) would be large and
cumbersome and would probably constitute a dangerous obstruction at an air-
port. Another approach, using selective absorption of infrared radiation to heat
the water vapor and carbon dioxide in the air, lay beyond the capability of cur-
rent (1938) technology. It was of theoretical interest, however, since it required
no cumbersome airport installations, just a properly designed invisible heat ray
to zap the fog at a distance.
n Chemical methods. Houghton’s own research program focused on the phys-
ical and radiative properties of condensation, fog, and clouds. His experiments
involved the use of calcium chloride as a chemical drying agent, which he sprayed
from an array of pipes installed over an airfield. other possible substances, most
with undesirable side effects, included silica gel, sulfuric acid, and certain strong
alkalis. For example, calcium oxide (quicklime) releases heat when it reacts with
atmospheric carbon dioxide and water vapor, but it is a caustic substance that
causes eye and skin irritation and requires proper storage and handling to avoid
spontaneous combustion. Thus it was deemed not suitable for field operations
involving aircraft. 32

Houghton was born in New York City and attended high school in Newton,
Massachusetts. He was educated at Drexel (B.S. 1926) and MIT (S. M. 1927),
receiving his degrees in electrical engineering. From 1928 to 1938, he served on
the staff of MIT’s Round Hill Research Division, where he and Bowles inves-
tigated the behavior of small water droplets as they formed and evaporated,
measured the transmission of visible light through fog, and developed chemi-
cal techniques for fog dissipation. Houghton became an assistant professor of
meteorology at MIT in 1939 and directed the department as associate professor
and executive officer (1942–1945) and professor and head (1946–1970). During
World War II, Houghton trained weather officers and served on a number of
national boards and military committees. After 1945, he chaired the meteorol-
ogy panel of the Pentagon’s Joint Research and Development Board, served on

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