Pittsburg dispatch. [volume] (Pittsburg [Pa.]) 1880-1923, 1891-10-01

there is no possibility of forgetting to tend
the central clock.
''Twiee every minute-at 20 seconds and
at 90 seconds-the clock automatically opens
the valve communicating with the receiver
described, permitting the discharge of the
contained air in the receiver to one and one
half pounds In less than 20 seconds the
air thus liberated has reached 10000 clocks
and forced upward small valve at each
clock, BY which the hands of the clocks are
made to move forward one minute;the valve
that liberated the air is then automatically
closed and the reducing valve opened, and
the receiver again charged with air, ready
for the next discharges until the operation
is continued.
''The location of the clock, though it may
be at the most remote part of the system,
makes no difference, the hand is advanced
with those on other clocks. In order to ac-
tuate the $1,000 clocks on the system, three
cubic meters, of 35. 5 cubic feet Of compressed
air, at ten pounds pressure per square inch,
is used per minute. It can be noted that
about 5000 clocks could be operated as we'll
bv the same expenditure of air. After the
clocks have thus been actuated by the air
it is allowed to escape from the pipes, which
usually requires SS seconds.
THE BIG MAIN STATION.
az next visited the large COMPRISING sta
tion, wherein can be found the history of
this wonderful and most complete air-com-
pressing system in the various designs OF
machinery, showing progressive improve
ment and development in the efficiency OF
the system as experience was gained and
the field of application broadened.
This great system found its origin in
small pneumatic clock system established
by Mr.. Popp in 1880 in Rue st. Anne, quite
near the commercial center of Paris. The
success of the undertaking and the con-
sequent growth of the system compelled the
establishment of new and lar-er central
COMPRISING station, which was erected in
the Rue st. Fargeau, nearly five miles from
the Chamber of Deputies, in the eastern
portion of the city, called Belleville.
owe first entered the old COMPRISING
room, where two single horizontal and one
beam COMPRISING engine were pointed out,
which up to a little less than three wears
ago, furnished all the air required in the
service. Now there are ten large cross COM
pound condensing engines operating 20 COM
pressors, representing 5000 horsepower,
which by next February will be increased
with the new plant to II, 900 horsepower.
After compression the air is forced at a
pressure varying from 81! to atmospheres
Il
or accumuiators arranged longitudinally
along the building in front of the COM
pressors. AS the front or street end of the
building is approached receivers are placed
higher, affording opportunity for the free
ing of water from the air before taking it
into the street mains.
SUCCESSFUL MOTOR SYSTEM
eve made an examination of the Me-
is being successfully operated and has been
in actual use for several years at Nantes,
France.
''The gauge of the track in Paris is feet
9 inches; the rails are the grooved pattern
The length of the track (single), including
branch line, is about four miles, with a very
great number of curves and excessive
grades-about feet in 100. The motors are
similar to an ordinary street car, having a
deck roof, upon which seats are arranged
for passengers as well as seats inside the
motor car, no seating capacity being occu-
pied by motor appliances.
1.-The engines operating the motor are of
slide valve design, protected from dust by
means of an apron and dust pipe compart-
ment below the seats of the car By rails
ing the apron by the side of the car the en-
Eines are exposed and can be examined if
desired. Under the floor of the car attached
to the frames are suspended series of nine
air receivers. the air being used from the
first three to make the down trip, and from
the second three for the return trip, the
other three being charged with air, which
can be used should emergency require.
"These receivers are connected with
small but round reheating device 20 inches
in diameter arranged in the forward plat
form of the motor, in which is arranged |
Iva
ling the pressure of air used in the engine. |
Each set of receivers has Independent |
throttling valves. The total weight of the |
motor is 10 tons, without passengers; and it |
can seat 80 of the latter -
Mr.. Gillian gives it as his opinion, after |
an extended study, that compressed air is |
already formidable competitor of the cable |
and electricity as a means of surface tran
sit.