Scott-Snell Lamp
Early form of a "high-pressure" gas lamp. Probably introduced
in the late 1890s. It included a novel and ingenious gas pressure raising
device. Provided in the tent of the gas lamp above the gas burner was
a hot air motor, which was actuated by the hot products from the combustion
of the gas. The gas on its way to the burner passed through a chamber which
contained a "displacer," the operation of which raised the pressure of the
gas to about 10" water column. At this pressure the gas was then conveyed by a
pipe to the gas ejector provided at the base of the burner. The gas issued
from the ejector at high velocity, entraining thereby a considerable
proportion of the air required for its combustion. The gas pressure raising
mechanism continues to operate so long as the gas continues to burn. The
system was later modified so that the air required for the combustion of
the gas was compressed to one pound per square inch, the gas being
used at the normal supply pressure. The lamps were used in Parliament Street
and the lighting of the old Vauxhall Bridge.
