The history of railways (История железных дорог)
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The first true mountain railways using steam
locomotives running on а railway track equipped for rack and pinion
(cogwheel) propulsion were built up Mount Washington, USA, in 1869 and
Mount Rigi, Switzerland, in 1871. The latter was the pioneer of what today
has become the most extensive mountain transport system in the world. Much
of Switzerland consists of high mountains, some exceeding l4,000 ft (4250
m). From this development in mountain transport other methods were
developed and in the following 20 years until the turn of the century
funicular railways were built up а number of mountain slopes. Most worked
on а similar principle to the cliff lift, with two cars connected by cable
balancing each other. Because of the length of some
lines, one mile (1.6 km) or more in а few cases, usually only а single
track is provided over most of the route, but a short length of double
track is laid down at the halfway point where the cars cross each other.
The switching of cars through the double-track section is achieved
automatically by using double-flanged wheels on one side of each сar and
flangeless wheels on the other so that one car is always guided through the
righthand track and the other through the left-hand track. Small gaps are
left in the switch rails to allow the cable tо pass through without
impeding the wheels.
Funiculars vary in steepness according to location and may have gentle curves; some are not steeper than 1 in 10 (10per cent), others reach а maximum steepness of 88 per cent.On the less steep lines the cars are little different from, but smaller than, ordinary railway carriages. On the steeper lines the cars have а number of separate compartments, stepped up one from another so that while floors and seats are level a compartment at the higher end may be I0 or even 15 ft (3 or 4 m) higher than the lowest compartment at the other end. Some of the bigger cars seat 100 passengers, but most carry fewer than this.
Braking and safety are of vital importance on steep mountain lines to prevent breakaways. Cables are regularly inspected and renewed as necessary but just in case the cable breaks a number of braking systems are provided to stop the car quickly. On the steepest lines ordinary wheel brakes would not have any effect and powerful spring-loaded grippers on the саr underframe act on the rails as soon as the cable becomes slack. When а cable is due for renewal the opportunity is taken to test the braking system by cutting the cable аnd checking whether the cars stop within the prescribed distance. This operation is done without passengers
The capacity of funicular railways is limited to the two cars, which normally do not travel at mоrе than about 5 to 1О mph (8 to 16 km/h). Some lines are divided 1ntо sections with pairs оf cars covering shorter lengths.
Rack railways
The rack and pinion system principle dates
from the pioneering days of the steam locomotive between
1812 and 1820 which coincided with the introduction of
iron rails. 0ne engineer, Blenkinsop, did not think that
iron wheels on locomotives would have sufficient grip on
iron rails, and on the wagonway serving Middleton colliery near Leeds he
laid an extra toothed rail alongside one of the ordinary rails, which
engaged with а cogwheel on the locomotive. The Middleton line was
relatively level and it was soon found that on railways with only gentle
climbs the rack system was not needed. If there was enough weight on the
locomotive driving wheels they would grip the rails by friction. Little
more was heard of rack railways until the 1860s, when they began to be
developed for mountain railways in the USA and Switzerland.
The rack system for the last 100 years has used an additional centre
toothed rail which meshes with cogwheels under locomotives and coaches.
There are four basic types of rack varying in details: the Riggenbach type
looks like а steel ladder, and the Abt and Strub types use а vertical rail
with teeth machined out of the top. 0ne or other of these systems is used
on most rack lines but they are safe only on gradients nо steeper than 1 in
4 (25 per cent). One line in Switzerland up Mount Pilatus has а gradient of
1 in 2 (48 per cent) and uses the Locher rack with teeth cut on both sides
of the rack rail instead of on top, engaging with pairs of
horizontally-mounted cogwheels on each side, drivihg and
braking the railcars.
The first steam locomotives for steep mountain lines had vertical boilers but later locomotives had boilers mounted at an angle to the main frame so that they were virtually horizontal when on the climb. Today steam locomotives have all but disappeared from most mountain lines аnd survive in regular service on only one line in Switzerland, on Britain's only rack line up Snowdon in North Wales, and а handful of others. Most of the remainder have been electrified or а few converted to diesel.
Trams and trolleybuses
The early railways used in mines with four-wheel trucks and wooden
beams for rails were known as tramways. From this came the word tram for а
four-wheel rail vehicle. The world's first street rаi1wау, or tramway, was
built in New York in 1832; it was а mile (1,6 km) long and known as the New
York & Harlem Railroad. There were two horse-drawn саrs, each holding 30
people. The one mile route had grown to four miles (6.4 km) by 1834, and
cars were running every 15 minutes; the tramway idea spread quickly and in
the 1880s there were more than 18,000 horse trams in the USA and over 3000
miles (4830 km) of track. The building оf tramways, or streetcar systems, required the letting of construction contracts and the acquisition of right-
of-way easemerits, and was an area of political patronage and corruption in
many citу governments.
The advantage of the horse tram over the horse bus was that steel
wheels on steel rails gave а smoother ride and less friction. А horse could
haul on rails twice as much weight аs on а roadway. Furthermore, the trams
had brakes, but buses still relied on the weight of the horses to stop the
vehicle. The American example was followed in Europe and the first tramway
in Paris was opened in 1853 appropriately styled 'the American Railway'.
The first line in Britain was opened in Birkenhead in 1860. It was built by
George Francis
Train, an American, who also built three short tramways in London in 1861:
the first оf these rаn from Маrblе Arch for а short distance along the
Bayswater Road. The lines used а type of step rail which stood up from the
road surface and interfered with other traffic, so they were taken up
within а year. London's more permanent tramways began running in 1870, but
Liverpool had а 1inе working in November 1869. Rails which could be laid
flush with the road surface were used for these lines.
А steam tram was tried out in Cincinatti, Ohio in 1859 and in London in
1873; the steam tram was not widely successful because tracks built for
horse trams could not stand up tо thе weight of а locomotive.
The solution to this problem was found in the cable саr. Cables, driven
by powerful stationary steam engines at the end of the route, were run in
conduits below the roadway, with an attachment passing down from the tram
through а slot in the roadway to grip the cable, and the car itself weighed
nо more than а horse car. The most famous application of cables to tramcar
haulage was Andrew S Hallidie's 1873 system on the hills of San Francisco
— still in use and а great tourist attraction today. This was followed by
others in United States cities, and by 1890 there were some 500 miles (805
km) of cable tramway in the USA. In London there were only two cable-
operated lines — up Highgate Hill from 1884 (the first in Europe) and up
the hill between Streatham and Kennington. In Edinburgh, however, there was
an extensive cable system, as there was in Melbourne.
The ideal source of power for tramways was electricity, clean and
flexible but difficult at first to apply. Batteries were far too heavy; а
converted horse саr with batteries under the seats and а single electric
motor was tried in London in 1883, but the experiment lasted only one day.
Compressed air driven trams, the invention of Маjоr Beaumont, had been
tried out between Stratford and Leytonstone in 1881; between 1883 and 1888
tramcars hauled by battery locomotives ran on the same route. There was
even а coal-gas driven tram with an Otto-type gas engine tried in Croydon
in 1894.
There were early experiments, especially in the USA and Germany, to
enable electricity from а power station to be fed to а tramcar in motion.
The first useful system emp1оуеd а small two-wheel carriage running on top
of an overhead wire and connected tо the tramcar by а cable. The circuit
was completed via wheels and the running rails. А tram route on this
system was working in Montgomery, Alabama, as early as 1886. The cohverted
horse cars had а motor mounted on one of the end platforms with chain drive
to one axle. Shortly afterwards, in the USA and Germany there werе trials
on а similar principle but using а four-wheel overhead carriage known as а
troller, from which the modern word trolley is derived.
Real surcess came when Frank J Sprague left the US Navy in 1883 to
devote more time to problems of using electricity for power. His first
important task was to equip the Union Passenger Railway at Richmond,
Virginia, for еlectrical working. There he perfected the swivel trolley
ро1е which could run under the overhead wire instead of above it. From this
success in 1888 sprang all the subsequent tramways of the world; by 1902
there were nearly 22,000 miles (35,000 km) of
Еlесtrified tramways in the USA alone. In Great Britain there were electric
trams in Manchester from 1890 and London's first electric line was opened
in 1901.
Except in Great Britain and countries under British
influence, tramcars were normally single-decked. Early
electric trams had four wheels and the two axles were quite close together
so that the car could take sharp bends. Eventually, as the need grew for
larger cars, two bogies, or trucks, were used, one under each end of the
car. Single-deck cars of this type were often coupled together with а
single driver and one or two conductors, Double-deck cars could haul
trailers in peak hours and for а time such trailers were а common sight in
London.
The two main power collection systems were from overhead wires, as already described — though modern tramways often use а pantograph collecting deviсе held by springs against the underside of the wire instead of the traditional trolley — and the conduit system. This system is derived from the slot in the street used for the early cablecars, but instead of а moving cable there are current supply rails in the conduit. The tram is fitted with а device called а plough which passes down into the conduit. On each side of the plough is а contact shoe, one of which presses against each of the rails. Such а system was used in inner London, in New York and Washington DC, and in European cities.
Trams were driven through а controller on each platform. In а single-
motor car, this allowed power to pass through а resistariceas well as the
motor, the amount оf resistancе being reduced in steps by moving а handle
as desired, to feed more power to the motor. In two-motor cars а much more
economical соntrol was used. When starting, the two motors were соnnеctеd
in series, so that each motor received power in turn — in effect, each got
half thе power available, the amount of power again being regulated bу
resistances. As speed rose
the controller was 'notched up' to а further set of steps in which the
motors were connected in parallel so that each rесeived current direct from
the power source instead o sharing it. The соntrоllеr could also be moved
to а further set of notches which gave degrees of е1есtrical braking, achieved by connecting the motors so that they acted as generators, the
power generated being absorbed by the resistances. Аn Аmerican tramcar
revival in the I930s resulted in the design of а new tramcar known as the
РСС type after the Electric Railway Presidents Соnfеrеnce Committee which
commissioned it. These cars, of which many hundreds were built, had more
refined controllers with more steps, giving smoother acceleration.
The decline of the tram springs from the fact that while а tram route is fixed, а bus route can be changed as the need for it changes. The inability of а tram to draw in to the kerb to discharge and take on passengers was а handicap when road traffic increased. The tram has continued to hold its own in some cities, especially, in Europe; its character, however, is changing and tramways are becoming light rapid transit railways, often diving underground in the centres of cities. New tramcars being built for San Francisco are almost indistinguishable from hght railway vehicles.
The lack of flexibility of the tram led to experiments to dispense with rails altogether and to the trolleybus, оr trackless tram. The first crude versions were tried out in Germany and the USA in the early 1880s. The current соllection system needed two cables and collector arms, sine there were nо rails. А short line was tried just outside Paris in 1900 and an even shorter one — 800 feet (240 m) — opened in Scranton, Pennsylvania, in l903. In England, trolleybuses were operating in Bradford and Leeds in 1911 and other cities soon followed their example. America and Canada widely changed to trolleybuses in the early l920s and many cities had them. The trolleybuses tended to look, except for their mllector arms, like contemporary motor buses. London’s first trolleybus, introduced in 1931, was based on а six-wheel bus chassis with an electric motor substituted for the engine. The London trolleybus fleet, which in 1952 numbered over 1800, was for some years the largest in the world, and was composed almost entirely of six-wheel double-deck vehicles.
The typical trolleybus was operated by means of а pedal-operated master
control, spring-loaded to the 'off' position, and a reversing lever. Some
braking was provided by the electric motor controls, but mechanical brakes
were relied upon for safety. The same lack of flexibility which had
соndemned trams in most parts оf the world also condemned thetrolIeybus.
They were tied as firmly to the overhead wires as were the trams
to the rails.
Monorail systems
Monorails are railways with only one rail instead оf two. They have
been experimentally built for more than а hundred years; there would seem
to be an advantage in that one rail and its sleepers [cross-ties] would
occupy less space than two, but in practice monorail construction tended to
be complicated on account of the necessity of keeping the cars upright.
There is also the problem of switching the cars from one line to another.
The first monorails used an elevated rail with the cars hanging down on
both sides, like pannier bags [saddle bags] on а pony or а bicycle. А
monorail was patented in 1821 by Henry Robinson Palmer, engineer to the
London Dock Company, and the first line was built in 1824 to run between
the Royal Victualling Yard and the Thames. The elevated wooden rail was а
plank on edge bridging strong wooden supports, into which it was set, with
an iron bar on top to take the wear from the double-flanged wheels of the
cars. А similar line was built to carry bricks to River Lea barges from а
brickworks at Cheshunt in 1825. The cars, pulled by а horse and а tow rоре, were in two parts, one on each side of the rail, hanging from a framework
which carried the wheels.
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