The Somerset herald. [volume] (Somerset, Pa.) 1870-1936, 1885-08-19
Air-Driven street Cars.

About two years since we deScrio-
ed system of air-driven tram cars
which was then about TO be adopted
on the Caledonian road line of the
( London Street Tramway Companv's S
system. This was the Mekarski
system, and the car which was then
experimental with was put on for
regular traffic, and was worked on
that line for about four months, TAX
ing its turn with the pair horse cars.
1t was intended then to displace the
whole of the hoisa-worked cars on
this line by ten air-driven cars, but
various delays occurred which pre-
vented effect being given to this in
tention until the present time. Now,
however, arrangements have been
completed, and the first ofthe series
of cars will very shortly be placed
on the line for regularly working,
to be followed in due course by the
other nine which are being built.
Since our previous notice, however,
several improvements have been in
troduced into the details OF the air
engines, which are now made upon
the compound principle. The high
pressure cylinder is 81 inches, and
the low pressure 5 inches in diane
ter, with an S-ineh stroke, and
through these the compressed AR
from the reservoirs is successively
used. Means are provided by
which the high pressure air can be
used IN the low pressure cylinder if
necessary. the engine house con-
tanning the air-compressing machin-
cry Is situated on the Holloway road
end of the tramway line, where there
are boilers, engines and pumps, by
means OF which atmospheric air is
compressed, at a pressure of 400
pounds per square inch, into reser-
voirs placed In the engine house.
From these reservoirs the air is con-
veyed to the tram-car through char
ging pipes with proper couplings,
which are connected up for charging
and disconnected when the reser-
voiTs on the car-whieh are placed
the platform-are charg-
ed to the necessary pressure. The
principal feature Of the system, how
ever, Is that the air in passing from
the reservoirs on the tram-car to the
cylinders of the engine il conducted
through boiling water and steam at
a pressure Of sixty pounds 20 the
square inch, which is contained IN
what is known as a hot-pot. This
hot-pot is charged at the compress
ing station, while the car reservoirs Z
are being filled with compressed air. /
By this means the heat which the
air takes up during the passage +
through the not water not only caus
es the air to expand, but prevents
the formation Of snow In the cylin-
1ers and at the exhaust. The work
ing pressure in the high-pressure
cylinders ranges from 80 pounds 1
down to fifty pounds per square
inch, and can be varied at will. /
There are efficient brake arrange
ments, and all the other require
ments Of the Board OF Trade have
been amply met. The first of the
series of cars for the Caledonian
road line was inspected last Satur-
lay at the Inventions Exhibition
BY number of gentlemen interest
I'd in tram-way locomotion. They
we're received by Captain Clipperton
,n behalf of the comDan Z, and the
of the engine and its
were explained by Mr..
Harris, for Sir Frederick Bramwell,
who is the engineer to the Mekarski
Company, but who was unayoida-
bly, absent. The car was run TO and
'ro on a short line in the south
promenade of the exhibition, its
powers being satisfactorily
demonstrated over such severe
curves "a could not occurin practice
We may add that the tram cars
upon the Mekarski system have
been successfully working on the
tramway lines at Nantes, IN France,
for the last six years.-LoHdon
Times.