make their product too rich; and such a condition is not
likely to occur except with vapor-gas when warm weather quickly succeeds
to a cold spell in the winter season. The consumer's immediate remedy in
any case is to use a smaller tip with the fishtail and batwing burners,
and a taller chimney with the argand; which devices will give a quicker
movement to the gas in one case and to the air in the other. The
smoking, however, may be caused by carbonic acid, which checks
combustion. There is always more or less of this in gas, arising from a
partial combustion in the retorts when charging them with coal or while
withdrawing the exhausted charge. But it is only by excessively slow and
careless work that this can happen to a serious extent. Only an expert
can tell when this condition exists, though if the symptoms do not yield
to manipulations of the chimney and tap, it may be suspected. There is
no effective remedy for this adulteration which can be applied by the
consumer except a vigorous complaint against the company which supplies
the stuff.

"There remains one burner or lamp to be mentioned, contrived with
special reference to health," he continued--"the ventilating standard
lamp of Doctor Faraday, used in the House of Lords. In this there is an
outer glass by which the vitiated air passes away through the pipe
communicating with the external air. The lamp is interesting, but there
is a question whether there is any practical advantage in its use.
Rutter's ventilating lamp is of different form, having a globe instead
of an outer cylinder, the gas and air coming in from above. Some of the
best dwellings now being erected in the vicinity of New York are
provided with tin pipes leading from the burners to the open air. In
some the pipe receives the foul air from an open metallic or mineral
shade over the burner; others have a larger pipe enclosing the gas-pipe
for ventilation, the tops of the two pipes (including the burner) being
enclosed by a globe pierced with holes for fresh air. There is said to
result a good ventilation, with economy of gas, an increased steadiness
of the flame and power of light. A better arrangement is a third pipe
enclosing the gas-pipe and enclosed in the ventilating-pipe, opening to
the air, instead of the holes in the globe, which in this case should be
air-tight. This plan is said to have reached its perfection when the
three pipes are filled with wire gauze to some extent. This, being
heat