Evening star., 1897-01-02
Comprcssed Air Contradictions.

There IS no denying that compressed air.
motive power, engages the attention Of
engineers and street railway managers as
promising possibility, and evidence comes
to hand with frequency to indicate the
eagerness with which final demonstrations
of the adaptability of this power to urban
conditions awaited by the practical oper-
ators of important lines. The Engineering
Magazine presents in Its latest issue
comprehensive study of the various uses to
which compressed air is being put. calling
that power the young giant among mod
ern motive energies. Local interest centers
OF course. in the question of the availability
of air to propel street cars, and on this
point the Magazine says:
Economy of operation is the crucial test
from the standpoint of the traction COM
panies. The features that appeal most to
the passengers and the public in general
are the doing away with poles, overhead
wires, and the continual excavating for
cables. pipes. or conduits. No fatal acci-
dents from live wires: no obStructing the
efforts of the fire department in moments
OF danger to life or property: no possibility
OF StallinS on railroad crossings in front of
approaching trains: no oostructing of the
. running of the cars by tampering with the
source or conductor of power during riots
or strikes; and no electrolysis of water and
gas-pipeS by escaping currents"
iHSSe potent factors from every point
of view in favor of such a motor. The En-
gineering Magazine goes on to discredit the
theory that the element of danger stands In
the way of its use, stating that whereas
the maximum pressure of the confined air
is but 2,o0o pounds to the square inch-this
pressure being reduced the moment the car
is started-the Mannesmann steel bottles
have been tested to 800 pounds bursting
then by ripping on the side in such a way
as TO involve no danger whatever to per
sons standing three feet away A French
electrical engineer was recently quoted as
disparaSing the safety of these motors as
serting that those in use in Lyons, France.
were regarded as dangerous, and that the
pressures In use there were but half as
great AS those required by the American
motors Thus there is a difference of eX-
pert opinion. that may possibly be traced to
personal predictions for or against this
power. resulting, nevertheless. In the utter
confusion of the unscientifc inquirers into
the subject. Notwithstanding the claims of
the Lyons engineer, il is known that the
compressed air cars are popular and sue
cessful in that city. in Nantes, in Berne and
in Paris. Yet mysterious explosion in
New York recently a line where a
compressed air motor is being tested is as
yet unexplained. and official silence has
given strength TO the impression that an
air tank under one of the experimental
motors gave way under the pressure. If
this was the case, the rending metal acted
differently from that which failed In the
test noted In the Engineering Magazine for
the floor of the car was driven to the cell
ing. The confused public would be grateful
for definite demonstrations other than
those inferentially given by the sdont;op
by transportation companies of other mo-
tive powers than compressed air after ex
perimenting with the latter To this end
an immediate and thorough local test
would be profitable. followed promptly, in
the event OF unsatisfactory results by in
stallation of the underground electric sys-
TEN.