Staunton spectator. [volume] (Staunton, Va.) 1849-1896, 1878-09-24

and machine shops, have just complete
for use on the Oakland and East Libert
passenger railway in Pittsburgh one c
the "Imboden vibrating steam sub-mo
tors" So entirely different is this in
ventlon from any other locomotive en-
gine we have ever seen or heard of tina
a brief description will be interesting t.
most readers in this age of mechanica
novelties and progress. This engine j
designed to superiede all horse power il
hauling street-cars, the most difficul
service to- which steam has ever beer
applied. Street railway tracks diffs
| widely from those of ordinary RAILWAYS
They form part of the street, and mus
conform to surface and grades up hill
and down. They are run on and owe
by all sorts of vehicles, and are dirtv
muddy and rough. They have frequen
delays, uneven crossings, and very
sharp curves around street corners
The load to be hauled is constantly va
rying from an empty car to as man,
people as can be crowded into and upoI
it.. Stopkages are necessary every few
hundred feet on all sorts of grades III
and downto take on or let off passen.
gers. To make average time q goot
speed must be maintained where ther,
is clear track, to compensate for :
snaiPs pace in crowded thoroughfarss
Instant stopping and often backing te
avoid accidents or collisions with wag-
ons or people must be provided for. tn,
engine must, therefore, be under abso-
lutte and certain control at all times. II
conform to modern ideas of comfort thu
passengers must be exempt from thu
annoyance of heat. dust, smoke, steam
and the smell of burning grease, and
the outside walking or driving public
and the inhabitants along the line in
sist upon silent and smokeless passage
of the machine. 1t is obvious, there
fore, that all these conditions require a
great modification in the form and op-
erations of the hitherto almost only rail-
way motor, the locomotive, with its
huge boiler, link-motion, connecting
rods, throttle and side valves, exposed
bearings, loud putting and laundering
clangor.
The general appearance of the I'M
boden sub-motor is striking. The en-
glne and car are two distinct affairs and
yet constitute single machine when
united. The engine has its own wheels
and frame. The two hind wheels are
80 inches in diameter, with the best
steel tires and secured on solid forged
steel crank axle inches in diameter.
The pilot wheels, Is inches in diameter,
are six feet in front of the drivers. They
are supplied with severed flexible axle,
allowing independent motion in the
wheels to facilitate curving, and yet are
as strong as solid axle and rigid wheels.
The boiler is horizontal, and in ex-
treme dimensions feet by 8, but is so
constructed as to furnish 12S feet of heat
ing surface in this small area. The nov.
city in the boiler consists in q separate
combustion chamber or smoke-box at
the end opposite the surface, with which
it is connected in 72 two-inch flues.-
The furnace fues and combustion cham.
Der are amply surrounded with water.
From this chamber the hot air and gases
are carried up through the steam dome,
the steam in its passage
to the smokestack. The boiler is con-
structed of the best quality of steel, and
in the opinion of experts would be safe
at 400 pounds pressure per inch, although
it will never be subjected to over $50
pounds on grade of even 800 feet to the
mile. 1t was built by the Pennsylva-
mia Railroad Company at their shops in
Altoona for McLanahan, Stone & Bal
ley, and Mr.. Nixon, the skilful foreman
of the boiler shops, proEounces it in
material, workmanship and design
equal, if not superior, to any boiler he
ever saw or had a hand in making, and
possessing for its size more steam
generating power. It is hung low be-
tween the axles.
The engine consists of two cylinders
8x10 inches, clamped at the base to a
"double barnacled" trunnion, which ex-
tends across the entire truck frame exact
ly midway between the aXles, parallel
to both and in the same horizontal plane
with the driving axle. The steam and
exhaust parts are in the clamping cylin-
der heads. There are corresponding parts
in movable, steam-tight port blocks or
guards" in the trunnions communicating
with the two channels in it. These ports
are alternately opened and closed by the
motion of the pistons as they rise and
fall with the crank motion. The direc-
ton in which the engine will run de-
pends upon the channel in the trunnion,
into which steam is admitted from the
boilers. Between the steam dome on
the boiler and the trunniOns there is in
terposed a double steam-cock chest, the
cock in one end of which controls and
directs the admission of steam to the up
per or lower channel in the trunnious
at the will of the engineer. The other
cock controls the exhaust or escaping
steam. These cocks are operated by
hand-levers, and their manipulation de-
termines the entire movement of the en-
gine having no valves to be deranged
or affected by high pressures-in fact, no
valves at all-permits use to be made
of the eXhust steam, which is claimed
by the inventor to be entirely novel.
One of the cocks in the steam-chest is
used to diminish or enlarge the passage
of the exhaust steam on its way to the
atmosphere. BY choking" the exhaust
back pressure on the piston is produced
and its movements retarded. If the ex-
haust is cut off entirely the piston is
stopped by a cushion of air-pressed and
imprisoned dead steam in the cylinders,
and the wheel is consequently locked"
on the track, although full head OF
steam may be on from the boilers. This
peculiar feature of the engine dispenses
entirely with brakes, for in running
down grades it is only necessary to close
the passage of the exhaust steam fal
enough to produce back pressure on
the pistons, and they are then made to
work as slow or as fast as the engineer
pleases, and the engine and car are held
under absolute control down the steep
est grade, and may be brought to stop
at any moment by completely "chok-
ing" the exhaust.
The engineer has his seat in hand
some little open cab on the top of the
boiler, and has nothing to attend to on
the srun" but the two cock levers. He
fires with anthracite coal at the start
and makes his run without further at
| tention to the fire. A novel arrange.
ment gives him perfect control over the
draught in the furnace by means of a
trap door in the combustion chamber.
The exhaust steam is carried through a
pipe in the chamber and super-heated
SO as to escape invisible into the atmos.
phere, and in winter portion of it will
be conducted through the car in one
| inch pipes arranged under the front Of
the seat to keep passengers warm. An
improved Shaw's nozzle in the smoke.
stack silences all putting sounds and al
Kissing from the safety valve. A De
Beaumont pump feeds the boiler with
water at boiling heat and returning te
the boilers about 25 per cent. of the ex
haust steam condensed in. heating tht
water. Immediately over the driving
axle there is bolster to carry the from