This paper, from Transactions of the Liverpool Engineering
Society, Volume 24, Society of Engineers (London, England), 1903,
was written by AR Ellison, an engineer who participated in the
construction of the Great Orme Tramway in
Llandudno, Wales. Unfortunately, the illustrations were not available in
the scans that I was able to find.
LIVERPOOL ENGINEERING SOCIETY.
TWENTY-NINTH SESSION.
TENTH MEETING -- 25th March, 1903.
THE GREAT ORME TRAMWAY.
By A. R. ELLISON.
The Great Orme's Head, near the town of Llandudno, is a promontory
rising abruptly from sea level to a height of about 700 feet. Llandudno
lies at the foot of the hill and practically at sea level.
The view from the summit of the Head has always been an attraction to
visitors, but the labour involved in climbing up the hill has deterred
many from making the ascent.
To bring the journey to the summit within the reach of all, the Great
Orme Tramway Co. was formed, and in 1897 Parliamentary powers were
obtained to construct a line starting from the town and terminating at
the top of the hill.
The work of construction commenced in 1901 and finished in 1902.
During the whole of the time the author acted as resident engineer to
the contractors.
The total length of the line is 1678 yards, exclusive of sidings. It
is divided into two sections: the lower one, the tramway, 828 yards in
length, and having an average gradient of 1 in 6.24, and the upper
section, the tramroad, 850 yards in length, with an average gradient of
1 in 16.4, both sections being 3 feet 6 inches gauge.
The terminus at the town is about 90 feet above O.D.; the end of the
tramway or first section is 490 feet above O.D., and the altitude of the
terminus at the summit is about 640 feet above O.D.
The maximum grade in the lower section is 1 in 4, and on the upper
section 1 in 10.5. (See Plate VI.)
The mode of traction adopted for both sections is, although not
novel, somewhat uncommon, viz. : cable haulage, the steam boilers and
hauling engines being erected at the junction between the upper and
lower sections.
In the case of the tramway the system is on the lines of an inclined
plane, with one car ascending while the other is descending, and
partially balancing each other, the additional power required being
supplied by the engines.
For the tramroad what might be termed an endless rope system is used,
a return pulley being fixed at the terminus on the summit, around which
the hauling rope passes, and on this section also, one car making a
journey up and the other coming down.
The permanent way in each section is differently constructed.
The lower section or tramway is laid for nearly the whole way on the
public road, or on the side of the road, and of necessity the cable has
to be carried under the surface in a conduit.
This section is divided into three lengths, a single track for the
lower length, a three rail or interlacing track for the upper length
(see Plate VI.), and a short length of double track for the passing
place joining the upper and lower lengths.
The upper length is laid as a three rail track in order that two
cables running in opposite directions should not be in the same conduit.
The distances from the centre of car at top to centre of passing
place and from centre of passing place to centre of car at bottom are
unequal, the top length being slightly the longer.
This is necessary by reason of the haulage drum attached to the
engines being divided into two parts, and two separate cables, one for
each car, being used, one on each half of the drum, i.e., the length of
cable required is equal to twice the length of the tramway.
In working this section the car starting from the top of the incline
has its cable entirely on its half of the drum, while the other half
width of the drum has practically none of the other cable on it, as the
other car at that time is at the foot of the incline.
The drum during the car journey makes a certain number of
revolutions, and the distance travelled at each revolution by either car
depends upon the diameter of its half of the drum.
The half width of the drum is equal to three feet, with a diameter on
the lagging of 5 feet 3 inches, and when holding 850 yards of 1 1/4-inch
cable is of necessity accommodating several layers or coils, and the
effective diameter when the drum is full being increased to about 6
feet.
The two halves of the drum are permanently keyed to the same shaft,
and when running the half of the drum hauling from the bottom increases
in diameter, while the half of the drum controlling the descending car
decreases; the position of the cars when meeting is at a point on the
line when half the total number of revolutions has been made, and at
that time each half of the drum will have an equal length of cable
coiled on it.
The times occupied from top and bottom to the passing place are
equal, and it follows that the speed of the cars must differ to the
extent that above the passing place the cars travel faster than below
the passing place, and therefore the distance travelled must be greater,
and the position of the passing place is below midway from top to
bottom.
The conduit is formed of 5 to 1 concrete and is 12 inches deep and 5
inches wide, the side walls and bottom are 6 inches thick -- on 75 feet and
100 feet curves the dimensions are increased to 7 inches wide at the
bottom with a 2-inch overhang at the top.
In all cases except on 75-feet and 100-feet curves the walls of the
conduit were laid straight between the pulley pits, but on 75-feet and
100-feet curves the walls were curved to the correct radii.
On the straight the pulley pits are 30 feet apart and 24 inches long,
15 inches wide, 20 inches deep, with 6-inch concrete walls, they are
built with sides vertical and not at right angles to the slope; on
400-feet curves the pulley pits are 15 feet apart; 200-feet curves, 10
feet; 100-feet and 75-feet curves, 7 feet 6 inches apart; the inside
dimensions on all curves are 18 inches long, 15 inches wide, and 12
inches deep.
At the upper and lower ends inspection pits are provided, each 50
feet long, 2 feet wide, and 2 feet 6 inches deep.
When laying the conduit, holes were left in the concrete for the rag
bolts, which secure the slot rails in position.
The zed rails forming the slot were of steel, 1/2-inch metal having
6-inch web, 3-inch top flange, 3 1/2-inch bottom flange in 30-feet lengths,
weighing 65 pounds per yard, cold straightened at works.
The slot is 1 1/4 inches wide, and when laid the distance between the
webs is 6 1/4 inches, the zed rails are fastened to the concrete conduit by 6
inches by 3/4-inch rag bolts 6 feet apart on the straight and 3 feet 9
inches on 100-feet and 75-feet curves, with additional bolts 6 inches
from the ends.
The rails with rag bolts attached were put in position and held in
place by distance pieces and clamps and the rag bolts run in with 2 to 1
cement mortar; on the bottom flange fish plates of 3/8-inch by 3 inches
iron were fixed at each joint.
As the toothed cams of the emergency brake when required act on the
inside of the web of the zed rails, great care had to be taken that the
distance of 6 1/4 inches between the webs was strictly adhered to.
In laying the zed rails little difficulty was experienced on the
straight or on curves of greater radius that 200 feet, but on sharper
curves, owing to the twisting of the web when curving, it was not easy
to obtain the necessary accuracy; after the first few attempts to bend
the rails with the jim crow had proved unsuccessful, rails were ordered
from the works curved to 100 feet and 75 feet radii, but even this was
not entirely successful though it reduced the labour on the ground; some
of the rails had eventually to be cut into 15 feet lengths partly
straightened and recurved. It was found best to use a large jim crow,
the most effective one being 5 feet between the arms, going through the
rails very lightly first on one flange and then on the other.
A difficulty in laying the zed rails occurred at a point on the line
known as the Black Gate, where the line is laid to a 75-feet curve and
has a change of gradient on the centre of the curve from 1 in 4 to 1 in
6.2; this necessitated bending the rails vertically as well as
horizontally, and it was successfully done by making 3 cuts, 3 feet
apart in each zed rail, with the rail saw through the bottom flange and
through the web to within 1 inch of the top flange. Special rag bolts 12
inches long and an extra thickness of concrete were provided here, and
the rails forced into their final position by tightening the nuts of the
rag bolts.
At the lower end of the passing place, where the centre slots of the
two tracks meet and merge into the one slot of the single track, the zed
rails had to be of extra strength as the inside wheels of each car cross
the slot belonging to the track of the other car. Special steel castings
were made with a thickness of metal in the top flange of 1 1/4-inch in
which grooves were cast to take the flanges of the running wheels.
The running rails are flat bottom rails of best steel, weighing 50
pounds per yard in 30 feet lengths, laid on 10 inches by 5 inches
creosoted pitch pine longitudinal sleepers for the single track, and
outside rails of the three rail track and on 12 inches by 6 inches
longitudinal sleepers along the centre of the three rail track, two
rails on the same sleepers.
To form the groove for the flange of the car wheels angle iron guards
are fixed at a distance of 1 inch from the head of the running rail; at
the Black Gate road crossing a heavier guard rail was necessary. The
rails were secured to the sleepers by 3/4-inch fang bolts and rail clips 5
feet apart, 7 pairs to a rail length, on the inside the rail clips
formed the seating for the angle iron guards, the fang bolts passing
through the angle iron, the rail clip and the sleeper.
On the outside of the rails two dog spikes were used between each fang bolt.
To keep the running rails to gauge tie bars of 2 1/2 inches and 3/8-inch
flat steel with 3/4-inch screwed ends were fixed every 6 feet on the
straight and every 3 feet 9 inches on 100 feet and 75 feet curves, the
screwed ends passed through the vertical side of the angle guards and
the web of the running rails and fastened to the rails with nuts on each
side of the web, the flat ends being secured to the bottom flange of the
zed rails at each rag bolt.
The rail joints had four hole fish plates 1 foot 6 inches in length
and weighing 18 pounds per pair, except on 75 feet and 100 feet curves
where 6 hole fish plates 2 feet 3 inches in length, weighing 28 pounds
per pair, were put in.
The pulleys in the conduit which carry the rope on the straight
lengths are vertical cast steel pulleys with sheaves 12 inches diameter
on the tread and flanges 1 1/2 inches deep, having cast steel pedestals 12
inches by 4 inches secured to the bottom of the pulley pits by 4 rag
bolts; the bolts were put in place when constructing the pulley pit. As
previously stated these pulleys are 30 feet apart.
The curve pulleys are cast steel hat pulleys and revolve on an axis
at right angles to the slope of the track; each pulley is 12 inches
diameter on the flange, 6 1/2 inches diameter at the top and tapering to 6
inches diameter at the bottom of the hat, with a height of 6 inches
turning on 4 inches by 1 1/4-inches steel pin, the pedestal is 8 inches by
8 inches at the base and 5 inches high, secured to bottom of pulley pit
by four rag bolts.
They are fixed at varying distances apart, according to the radius of
the curve, and in positions so as to keep the cable clear of the sides
of the conduit, and also that the hauling lever attached to the car will
pass.
The flange of the curve pulleys is 14 inches below the upper surface
of the slot and 4 inches above the bottom of the conduit.
The pulleys as designed were effective except where there was a
sudden change of grade, when it was found that the cable had a tendency
to mount on the top of the hat, and an extra height of 2 1/2 inches was
added to all such pulleys to counteract this tendency.
The straight pulleys and curve pulleys are constructed so as to be
taken out of the conduit for repairs and renewals, and the pulley pits
are fitted with a cast-iron movable cover. The track was laid without
any superelevation of the outer rail at curves.
The component parts of the permanent way and adjuncts have now been
described, and when all had been laid and secured, the surface of the
track was made up to rail level by concrete 7 inches thick between the
track rails and slot rails, and for 12 inches on the outside of the
track (not under the supervision of the author).
The drainage of the conduit is provided for and connections are made
in several places to the surface water drains of the road authority. At
each pulley pit a 2-inch diameter hole is made through the bottom
concrete to take by leakage any water standing in the pits, which in the
case of the straight pulleys are 8 inches below the bottom of the
conduit.
Before proceeding to describe the tramroad it will perhaps be better
to give a few details of the cars.
On the tramway two cars coupled together are intended to form a
train, one car for passengers and one car for luggage, the latter known
as the jockey car, the cable to be attached to this car. Up to the time
of writing it has not been necessary to use the cars coupled together,
both type of car has been used separately.
The passenger cars have accommodation for 60 passengers, 48 sitting,
12 standing, and are 38 feet 10 inches overall length, 7 feet 6 inches
over all width, fitted with 2 four-wheel bogies 23 feet apart centre to
centre, the wheel base of each bogie is 3 feet 9 inches; total weight of
each car is 6 1/2 tons.
The cars have cross seats with a central corridor, semi-open sides
fitted with sun blinds, and conductor's platforms at either end. The
seats are hollowed out to allow for the gradient.
Buffers with a horizontal radial movement are fitted at each end.
There are 13 brakes fitted to each car, 1 rim brake on each wheel, 2
slipper brakes, working on the track rails, for each bogie and one
conduit emergency brake fixed in a pocket under the centre of the upper
bogie; the cable is attached to the car at this emergency brake.
The rim brakes are all arranged so as to be actuated from brake
wheels on the platforms and can be worked from either or both ends of
the cars.
The jockey cars are 16 feet 7 inches over all length; 7 feet 6 inches
over all width; with a wheel base of 4 feet 3 inches; the body of the
cars is 10 feet by 7 feet 6 inches, with windows and doors both ends,
double folding doors at the sides and platforms at the ends; wheel and
slipper brakes as on the passenger cars, and having a pocket on the
underframe to which the haulage attachment and emergency brake is fitted
when required. Weight of car 3 tons.
The cables are of steel wire with a hemp core 1 1/4 inches diameter
with a breaking strain of 62 tons.
The emergency brake (see Plate VI.), which was designed for this
tramway, is deserving of special mention. It is so arranged that if the
cable parts and the strain on it is reduced, steel jaws are released and
forced on to the inner sides of the web of the zed rails and thereby
prevent the cars running down the incline. As the brake works entirely
inside the conduit the formation of snow or ice has no effect on its
action.
The brake consists of a carrier and a bracket.
The carrier is of 10 inches by 6 inches H section steel, fitting into
a pocket provided in the bogie framework, the upper flange of the
carrier is securely bolted to the angle iron of the pocket; side plates,
5 inches by 5/8-inch are bolted to the web and extended forwards to carry
the haulage lever.
The bottom of the carrier is provided with a bracket for the purpose
of carrying the drawbar, brake cams and links. The brake cams working
horizontally on steel pins are of the best tool steel, hardened on the
teeth, which are designed so that as one wears out the next one comes
into engagement with the webs of the zed rails. The cams are operated by
four steel links attached thereto, and to the draw bar by means of
turned pins.
The steel draw bar, 2 inches in diameter, passes through the centre
of the bracket, having on its trailing end a powerful steel spring which
is compressed between a nut on the end of the bar and the body of the
bracket.
The cable is attached to the lower end of the haulage lever and
carried 10 inches below the surface of the zed rails, the lever passes
through the slot and its upper end is free to move on a pin connected
with the side plates previously mentioned, the drawbar passing through
the bracket is fastened to the haulage lever midway between its rope
pins and the top of the lever.
In its normal position the spring is arranged to keep the points of
the brake cam teeth projecting beyond the sides of the bracket and
bearing against the sides of the zed rails, but immediately strain is
put on the rope the drawbar is pulled forward, at the same time drawing
the teeth of the cams out of contact with the zed rails and compressing
the tail spring, which action is utilized as a spring drawgear. If the
rope breaks or becomes detached from the hauling lever, the spring
immediately pulls back the drawbar, and at the same time brings the
teeth of the cams into contact with the webs of the zed rails, when,
owing to these cams being of an eccentrical shape, the weight of the car
trying to run down the hill forces the teeth still harder into the zed
rails. Each cam is capable of independent action within certain limits
and this ensures an equal bearing on each side of the conduit.
The tramroad section in its construction does not possess any of the
characteristics of the tramway.
The tramroad consists of a single track only with a passing place
midway.
The permanent way has no conduit, the rope being carried above ground
level, and the track is entirely laid on land acquired by the Company,
and not upon public roads; two level crossings only having to be
provided.
As shown by the horizontal section the track follows the original
surface very nearly, there being a short embankment and cutting at and
above the passing place.
On the formation is placed pitching about 7 inches thick, on which
the cross sleepers are laid, packed and boxed in with ballast in much
the usual way.
The sleepers are 6 feet by 9 inches by 4 1/2 inches creosoted Baltic
timber, laid 2 feet apart.
The running rails are similar to those on the tramway and secured to
the sleepers at centre and ends by 3/4-inch fang bolts and rail clips, six
to each rail length, and with dog spikes on each side of the flange at
all sleepers not occupied by fang bolts.
The curves on the tramroad are not less than 200 feet radius, except
at the passing place.
The curves of 200 feet radius and under have tie bars of 2 1/2 inches by
3/8-inch steel 6 feet apart fixed under the bottom flange of the rail.
A double set of pulleys and rollers is necessary, i.e., one set to
carry each rope; rollers, 4 inches diameter and 12 inches in length, are
fixed on the straight. The hat pulleys on the curves are of similar
design as on the tramway, those on the inside of the curves being of the
same dimensions, those fixed on the centre line of the track having
3 1/2-inch diameters.
These pulleys are secured to the sleepers by 3/4-inch coach screws, 4
to each pedestal.
The point of attachment of the cables to the cars is 4 1/2 inches out of
the centre line of the cars and on opposite sides of the centre line of
the track for each car, and it is carried down as near as possible to
the rail level, being 3 inches above, the cables being 7/8-inch diameter.
The pulleys and rollers are fixed so that this attachment will pass.
The special work on the track has been at the passing place, and in
laying the track this short length only presented any difficulty.
This arose from the fact that the cable had to be passed under the
level of the track rails at the crossings at the upper and lower ends of
the passing place.
V crossings were manufactured to provide the opening through
which the rope had to pass, and a few experiments when the line was near
completion assisted in deciding the exact points at which to place the
special pulleys and guides, and the arrangement is effective.
The return pulley at the summit is 5 feet in diameter, with deep V
flanges and radial arms. It is horizontally fixed on a strong concrete
base, on which also are placed the guiding pulleys necessary to keep the
cable from slipping out of position.
The hauling drums for the tramroad are similiar to the drums for the
tramway, one rope being fastened to each half of the drum for each car,
and a rope passing round the return pulley connecting the cars, the
length of cable required being three times the length of the tramroad.
This system of haulage made necessary special tension gear to deal with
the excess of rope paid off from the half of the drum connected with the
ascending car.
This was an arrangement of a series of pulleys, one set for each
cable, and each set consisted of 11 pulleys, six (loose) pulleys on the
same axis permanently fixed in a cast-iron frame approximately at rail
level, and five others immediately underneath, running on a common axis
fixed to a frame which is free to move vertically downwards on guides.
The hauling cable is coiled over and under each pulley of the set,
leading from the drum over the top of one of the upper pulleys under the
corresponding lower pulley, and so on, finally going over the top of the
last upper pulley attached to the car.
The lower five pulleys have an additional weight of 10 cwts. fixed to
their movable frame.
These latter pulleys in action move up and down a pit and have a
maximum vertical motion of 6 feet, and when the ascending car is taking
its cable from the half width of the drum, the movable pulleys, by their
tendency to travel down the pit, absorb the excess of cable paid off
from the drum and so provide that the trailing cable is always kept taut
behind the car and in its position on the track.
The two passenger cars for the tramroad are similar to those for the
tramway, with the exception of the cable attachment. The emergency
conduit brake is not necessary, and the cables being secured to the fore
and aft bogies 4 1/2 inches out of the centre line of each car.
POWER STATION.
The boilers and engines are erected in a suitable building on the
plateau and approximately midway between the commencement of the tramway
and the summit of the tramroad.
The plant consists of one loco-type multitubular boiler 15 feet in
length, 4 feet in diameter, and one vertical boiler 13 feet by 5 feet
with the necessary feed pumps. The working steam pressure is 80 pounds
per square inch.
The engines for the tramway and tramroad are horizontal high
pressure, non condensing and of similar design, the former a pair of
12-inch cylinders 14 inches stroke, and the latter a pair of 10-inch
cylinders and 12 inches stroke. The hauling drums are 5 feet 3 inches
diameter, 6 feet 6 inches in width, with a break ring in the middle
dividing the drums into two parts, helical gearing 5 to 1.
The engine beds are formed of steel girders embedded in concrete.
Levers actuated by cams worked by worm wheels attached to drum shafts
assist in guiding the cables on to the drums.
An indicator connected to the drum shaft shows the position of the
cars at any part of the journey.
SIGNALLING.
An efficient means of transmitting signals from the cars at any time,
whether in motion or not, to the engine house, was absolutely necessary.
Poles with bracket arms are put up along the whole route at suitable
distances apart, supporting a copper wire in the same way as for an
electric tramway.
To the roof of each car a trolley pole is fixed, and on the car
platforms telephones are placed electrically connected to the trolley
wheel, the circuit being completed by carrying the arms to the steel
framework of the bogies.
At the engine house an extra large bell is provided.
Col. Von Donop, after his inspection on 30th July, reported that he
would recommend the Board of Trade to certify the line as fit for
passenger traffic; the line was thereupon opened to the public next day.
Between 31st July and 26th December, inclusive, 76,000 passengers were carried.
DISCUSSION.
Mr. Walwyn White said -- Of course I am rather interested in this
tramway. When my firm took the work of installing it we had considerable
difficulties to overcome, the greatest difficulty, of course, being the
very steep gradients. We could not have the rack railway, as adopted in
the case of Snowdon, because we were bound to provide for the surface
traffic up the old road. We were bound to use hauling ropes, as the
gradient was too steep for adhesion only. There is no other line of the
sort in this country, so we had nowhere to go for lessons, and we had to
worry out the difficulties for ourselves. However, thanks to the
assistance we received from Mr. Fowler and the author, we were able to
overcome the whole of them satisfactorily, and to complete a unique
tramway.
Mr. George White (Manager of the Great Orme Tramway Company) said --
Having been called upon by the Chairman, I have only to say that the
line promises to be very successful, and so soon as certain small
alterations to the gradient at the engine house are finished, probably
in the course of next week, we shall start running again. I am pleased
to state that the manner in which the author carried out the work is
most satisfactory.
Mr. F. E. Cooper said -- One or two points have occurred to me, one
thing particularly, and that is with reference to the making up of the
carriageway between the rails. As I understand, the concrete is brought
up to the surface of the tramway, and Mr. White, in speaking of it now,
mentioned that it was found necessary to accommodate the ordinary
traffic I do not know whether that means vehicular traffic, but I should
rather like to know how the concrete is put in, because on such a
gradient as this, with ordinary concrete, vehicular traffic would be
carried on with difficulty.
I sympathise very much with Mr. White and the author in the matter of
the zed rails on the sharp curves. I am glad to say we have no zed rails
on the Liverpool Tramways. We have had experience with 30 feet and 60
feet rails and we know that curving at the works is not always quite
satisfactory, when the material reaches the site of the work, owing to
the jolting during the carriage of the rails causing the curve to be
varied.
I see that the track was laid without any superelevation at the
curves, but the cars being mounted on bogies would relieve the friction
on tne curves a great deal. Our own experience is that by putting in a
little superelevation the wear on the rails is reduced immensely,
particularly where there is a cross gradient in the street.
I think that the automatic brake arrangement seems a very good one.
No doubt provision has been made in the zed rail for the scraping of the
rail, because, although I understand that Col. Von Donop says that the
cars should not stop except at terminal stations, I suppose occasionally
they must do so in between, and I presume as soon as they do stop, the
brake comes into operation and scrapes the rail on the inside.
Mr. Thomas Duncanson said -- I think the Society is very much
indebted to the author for his interesting description of this tramway,
and for the excellent photographs which he has shown to us.
I should be interested if he can tell us what the cost of the work was.
One point which strikes me is this, the line is only a mile long, yet
it has two distinct methods of construction involving transhipment of
passengers half-way; it would have been a considerable advantage to have
had it all on one system. Is there any insuperable reason why it was not
so arranged?
Mr. J-. N. Nicholson said -- The author
states that the conduit walls are formed of concrete six inches thick.
Seeing that the emergency brake acts on to the zed rails, would the
author mind telling us if he has noticed any ill effect on the concrete
walls or any displacement of the rag bolts in them. The walls seem
rather thin.
With regard to the line itself, I do not think I would care to travel
on it. It looks rather dangerous. On the other hand I should not travel
on it on account of its safety. Anyone who has felt that emergency brake
act does not soon forget it.
As to the conduit, the author tells us that on the 75 feet and 100
feet curves the walls were curved to the correct radii. As the rope
itself will be in a straight line from pulley to pulley, I cannot see
any advantage in curving the concrete work, as it is always adding to
the expense of working. It may be, however, that the gripper bar requires
this curving.
Then there is another point I cannot quite follow. One car is
intended for passengers and one car for luggage. What does the luggage
destined for the top of the Great Orme consist of?
Mr. Frank
E. Priest (the Chairman) said -- Before asking the author to reply I
should like to add to the somewhat numerous questions he has to deal
with, one concerning the operation of the telephone arrangement on the
cars. Is the arrangement successful? One's experience of telephones is
that very little serves to put them out of working order, and it occurs
to me that a car travelling on a gradient of 1 in 4 might possibly cause
some disturbance of the telephonic system.
Mr. Ellison, in reply, said -- With regard to the surface of the
finished track. Practically no vehicles go along the line. The
only point where any vehicular traffic does cross is at the Black Gate,
and here granite setts have been laid to form foot-holds for the horses.
Some doubt seems to exist as to the action of the emergency brake,
which is entirely automatic and does not come into play unless there is
slack in the rope or the rope parts. The hand brakes only affect it
indirectly, viz. : -- If you apply the hand brakes (on the descending
car) without warning the engine house, the rope slackens and the
emergency brake comes into operation.
The telephone system is very successful, because the cars only travel
four miles an hour, and therefore little difficulty is experienced
through the trolley head leaving the wire.
The concrete was laid between the slot rails and the running rails.
The emergency brakes have never given any trouble except at the upper
terminus; here the starting gradient was 1 in 20 and had to be altered
to 1 in 15.
The track has never suffered any ill effects through the working of
the emergency brakes, the only result of an application being to leave
teeth marks in the webs of the zed rails.
The jockey cars were really intended for taking coffins up to the cemetery.
The line was constructed in two systems owing to the extra cost that
would have been involved if the conduit system had been adopted for the
entire length.
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