IMPROVEMENTS IN CARRIAGES AND LOCOMOTIVE ENGINES FOR WORKING ON STEEP INCLINES AND SHARP CURVES, BUT SOME OF THEM APPLICABLE TO LOCO- MOTIVE ENGINES GENERALLY
Year: 1868

page_text: PROVISIONAL SPECIFICATION left by Andrew Alexander at the Office
of the Commissioners of Patents, with his Petition, on the 2nd July
1868.
I, ANDREW ALEXANDER, of Herne Villa, Belvidere, in the County of
Kent, Engineer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN CARRIAGES AND LOCOMOTIVE ENGINES FOR WORKING ON
STEEP INCLINES AND SHARP CURVES, BUT SOME OF THEM APPLICABLE TO LOCO-
MOTIVE ENGINES GENERALLY," to be as follows:-
I apply a water pipe led into the base of the engine blast pipe and
proceeding therefrom to the barrel of the boiler below the water line or
to the water tank of the engine, the pipe being closed by a small cock
which can be opened or shut at the pleasure of the engine driver. The
object of this pipe & cock is to enable the engine to run without
steam down long inclines without damage to the working faces of the
valves or pistons while the train is retarded by the back pressure of the
atmospheric air in the cylinders, and also to prevent the packing in
the glands of piston or valve rods being burned by the heat of the
compressed air. For this purpose in descending a long incline the
engine is placed by the driver more or less in back gear and the water

page_text: cock above described more or less opened, the waste water cocks on the
cylinder being also partially opened. A small stream of water is thus
allowed to flow into the base of blast pipe, whence it is sucked in spray
by the entering air among the valves and pistons, any excess escaping
by the waste water cocks.
Also I form the barrel of the boilers of locomotive engines with bevilled
ends, so that the axis of the barrel is not square with the outer fire-box
shell as usual, but points downward from it. The same object may be
attained to a certain extent by placing the boiler formed in the usual
manner on the frames with the fire-box higher than the smoke box end.
By these arrangements on steep inclines a considerable deviation from
the level may occur without the water level falling below either the fire-
box or tubes at the smoke box end, which would be dangerous.
Also I apply both to engines & carriages wheels formed in two parts, the
inner part or disc being keyed in the ordinary manner to the axle, while
the circumference of this inner part is rounded to fit a corresponding
hollow turned in the inner circumference of the outer part or annular
disc. The outer can thus move upon the inner disc to a certain extent
(being hindered by stops, which both act as keys and limit the extent of
motion) in the manner of a ball and socket. The outside of the tyre or
tread of such wheels should be hollowed in the manner of tyres which
have for some time been at work, and when the wheel arrives at curves
its outer part can maintain itself constantly parallel to the tangent of
the curve, thus avoiding the flange friction incurred with ordinary
wheels. By making the inner disc large enough on coupled engine
wheels to receive a crank pin such wheels may be coupled, while the
tyres assume the position they would assume with a radiating axle.
Also I modify the regulator valve of locomotives so as to prevent
slipping in ordinary cases. This is specially applicable to mountain
railway engines with more than one pair of cylinders, in which it is
sometimes found difficult to adjust the supply of steam to each pair so
as to get them to work well together without the slipping of one or
other. The modification referred to consists in casting in one piece with
the regulator slide an entrance pipe provided with a valve and spring
(which latter can be tempered or adjusted by a stem passing through a
stuffing box on the top of the steam dome). Through this entrance pipe
and valve the steam passes before it enters the apertures of the regulator
face, but on a sudden increase of pressure on the spring caused by the

page_text: slipping of the engine driving wheels the spring yields & partially
closes the valve, thus diminishing the supply of steam. A small hole
about of an inch in diameter is bored through the valve so as to restore
the equilibrium should the valve be entirely closed by the sudden
pressure.
Also I apply to central-rail engines with vertical axles & horizontal
wheels (such as those designed by me for the Mont Cenis Railway
Company) a mode of coupling the inner vertical axles by using one
beam only with links connecting each end to cranks on the vertical
axles. Up to the present time two beams have been used with links,
the beams being also linked to each other at the centre line of the
engine. I now employ one beam only with an off-set at the centre, by
which it is joined by a short link to a fixed pin in the centre line of the
engine. The effect of this arrangement is to give a slight backward
and forward motion to the beam as it reciprocates, which compensates for
the virtual variation of lengths arising from the varying inclination of
the connecting links joining the ends of the beam to the cranks on
the vertical axles, & hence each space passed over by the one crank
corresponds to an equal space passed over by the other crank.
Also I apply a moveable glass guage to locomotives for steep inclines
moved by the action of a weight inside the boiler. Up to the present
time one long or two shorter glass guages of ordinary construction have
been used, the position of the top of tubes and of the fire-box being
marked on them for different rates of gradient. As with this arrange-
ment the water may be visible in the glass gauge while the water level
is actually below some part of the heating surface, there is great risk of
serious damage or accident unless the driver intelligently understands
its indications. To avoid this risk I make the bottom of the guage tube
when the engine is on the level to correspond with the point near the
centre of boiler below which the water should never fall on whatever
incline the engine may be standing; and by the application of the
weight, as described, the gauge rises & falls, so that the bottom of the
glass always fairly represents this point, and in consequence so long as
the water is in sight the boiler is safe; or I place the weight outside
(preferably below the foot plate) & make it act either on the water tube
or on a metal sliding bar, which represents the point below which the
water should never fall (the water tube being in this latter case stationary),

page_text: and so long as the water can be observed above this sliding bar the boiler
is safe.
Also I apply a reversing lever which can be moved by hand as usual
or by a screw. This screw is straight & uniform in diameter from end
to end, & is turned by a wheel at one end of the carrying frame. The
detent of the reversing lever descends into the thread of the screw. The
bottom end of the lever can slide vertically for a short distance in a
small slot in the carrying frame, and it is controlled therein by a short
link fixed at one end to the frame and at the other to the reversing lever
so as to form a parallel motion, which keeps the motion of the stop or
detent parallel to the screw as the reversing lever is pulled backward or
forward.
Also I apply to central-rail engines (or engines which avail themselves
of the supplementary adhesion resulting from the pressure of wheels
upon a central rail, as proposed and patented at various times in and
from the year 1831,) vertical wheels for acting upon such central rail or
rails. These wheels are mounted on horizontal axles and can therefore
be coupled in the ordinary manner to the other or carrying axles of the
locomotive engine, and in some cases the horizontal axles for the central-
rail vertical wheels may also form the carrying axles of the engine.
These vertical wheels act upon the central rail or rails by their faces or
discs, the tyres on such wheels being fixed, not (as usual) on the cir-
cumference of such wheels, but on the surface of each disc close to the
perimeter. A wheel is placed on each side of the central rail or rails;
these wheels with the horizontal axle on which they are placed turn
together, and can also be drawn together by screws so as to nip or bite.
the central rail between each contiguous wheel face. By this application
a certain amount of increased friction arises from the grinding action
between wheel and rail, but this is more than compensated by the entire
absence of all axle friction arising from the pressure with which the
wheels (which are horizontal in all central-rail engines hitherto pro-
posed) are squeezed against the central rail. In the above application
of vertical wheels, as described, there is no axle friction whatever due to
the pressure against central rail, as each wheel acts as the fulcrum or
point of support for the other. Springs are interposed between the
screws which draw the vertical wheels together and the wheels. By
this method of obtaining pressure upon the central rail or rails great

page_text: additional complication is avoided, the machinery is more accessible, the
lubrication may be much more effective, & much less is required; also
there is an absence of all liability to lubricate the central rail, as at
present occurs with central-rail engines having horizontal wheels,
vertical axles, and a number of vertical journals or bearings, from which
the oil naturally runs. With the object of reducing the grinding action
between the vertical wheels and the central rail the wheels may in
some cases be enlarged, while to maintain the same tractive force a
geared engine is employed.