The mirror., 1922-06-22

caloric engines, for operating hosting en-
gines in warehouses in New York followed
by a practical system for running sewing
machines in large numbers from central
station by the transmission of compressed
air to small motors on the machines.
Compressed air for high working pres
sures, generated by hydraulic pressure and
the use of waterfalls, was an improvement
on the antiquated methods by use of the
trompe. The direct pressure system was
brought into use by Sommeiler at the
Mont Gents tunnel in 1872 and did good
work at that time; but as it required as
much water to compress the air as was
equal to the amount of free air compressed,
the system was applicable only in favor
able localities, and has now dropped out
of use. Many patents have since been
issued on direct acting hydraulic COM
pressors, but the principle is not economi-
cal in practice, and no compressors of this
class are in use at the present time.
The trompe system has been greatly i'm
proved and extended for high pressure,
with large flow of water with moderate
head, by making deep pit with an air
chamber at the bottom and returning the
water to the football as in an inverted
siphon. This was first demonstrated in
experiments by Mr.. ]. P. Fizell, of Boston,
in 1877, and patented 1878. 1t has been
finally put in practical operation by Mr..
c. H. Taylor in large installments OF
hydraulic plants at Magog, near Montreal,
and at Ainsworth, British Columbia. Both
plants have proved success, and the utili-
cation of water power for compression of
air and its transmission for all power pur-
poses is thereby assured The vertical
excavated shafts may not be needed where
steep slopes, or chasms, or mountain sides
are available. The moving water will
carry air down slope as well as by
vertical shaft, and the return pipe only
follows the same line back, so that the
flow line is the only loss in efficiency
Compressed air for street railways was
continually agitated by newspapers and
promoters during the middle of the nine
teenth century. But little practical progress
was made, much of the difficulties and
Instructions being due probably to the dis
trust of the moneyed interest of schemes
that had no practical and reliable test and
trials. In 1862 Gardner D. Hiscox, made
plans for light streetcar railway system
with compressed air storage under the
seats and on top of the car, with the en-
gines under the platform, so that the pas
senger accommodation was not interferred
with. The air pressure of ESQ pounds
was to be supplied from station storage
tanks and compressor on the line. The
plans did not meet with financial en-
couragement, and proved to be premature.
The horse was not yet ready to 60. An
other generation was needed to bring
compressed air power for railways to
financial acceptance.
Further progress was made about 1873
in the intercooling of compressed air in
the cylinders by water jets or sprays, in
the compressors at the St. Gothard tunnel.
This led to still further Improvements and
economics in the construction of air COM
pressing machines, until at the present day
there seems to be nothing but change of
detail in construction that may not always
result in improvement.