The history of railways ( )


The history of railways ( )

The history of railways

The railway is good example of system evolved in variousplaces to

fulfil need and then developed empirically. In essence it consists f

parallel tracks or bars of metal or wood, supported transversely by other

bars stone, wood, steel and concrete have been used so that th load of

the vehicle is spread evenly through the substructure. Such tracks were

used in the Middle Ages for mining tramways in Europe; railways came to

England in the 16th century and went back to Europe in the 19th century as

an English invention.

English railways

The first Act of Parliament for railway, giving right of way over

other people's property, was passed

in 1758, and the first for public railway, to carry the traffic of all

comers, dates from 1801. The Stockton and Dailington Railway, opened on 27

September 1825, was the first public steam railway in the world, although

it had only one locomotive and relied on horse traction for the most part,

with stationary steam engines for working inclined planes.

The obvious advantages of railways as means of conveying heavy loads

and passengers brought about proliferation of projects. The Liverpool &

Manchester, 30 miles (48 km) long and including formidable engineering

problems, became the classic example of steam railway for general

carriage. It opened on 15 September 1830 in the presence of the Duke of

Wellington, who had been Prime Minister until earlier in the year. On

opening day, the train stopped for water and the passengers alighted on to

the opposite track; another locomotive came along and William Huskisson, an

and great advocate of the railway, was killed. Despite this tragedy

the railway was great success; in its first year of operation, revenue

from passenger service was more than ten times that anticipated. Over 2500

miles of railway had been authorized in Britain and nearly 1500 completed

by 1840.

Britain presented the world with complete system for the construction

and operation of railways. Solutions were found to civil engineering

problems, motive power designs and the details of rolling stock. The

natural result of these achievements was the calling in of British

engineers to provide railways in France, where as consequence left-hand

rujning is still in force over many lines.

Track gauges

While the majority of railways in Britain adopted the 4 ft 8.5 inch

(1.43 m) gauge of the Stockton &

Darlington Railway, the Great Western, on the advice of its brilliant but

eccentric engineer Isambard Kingdom Brunel, had been laid to seven foot

(2.13 m) gauge, as were many of its associates. The resultant inconvenience

to traders caused the Gauge of Railways Act in 1846, requiring standard

gauge on all railways unless specially authorized. The last seven-foot

gauge on the Great Western was not converted until 1892.

The narrower the gauge the less expensive the construction and

maintenance of the railway; narrow gauges have been common in

underdeveloped parts of the world and in mountainous areas. In 1863 steam

traction was applied to the 1 ft 11.5 inch (0.85 m) Festiniog Railway 1n

Wales, for which locomotives were built to the designs of Robert Fairlie.

then led campaign for the construction of narrow gauges. As result

of the export of English engineering and rolling stock, however, most North

American and European railways have been built to the standard gauge,

except in Finland and Russia, where the gauge is five feet (1.5 m).

Transcontinental lines

The first public railway was opened in America in 1830, after which rapid

development tookplace. famous 4-2-0 locomotive called the Pioneer first

ran from Chicago in 1848, and that city became one of the largest rail

centres in the world. The Atlantic and the Pacific oceans were first linked

on 9 1869, in famous ceremony at the meeting point of the Union

Pacific and Central Pacific lines at Promontory Point in the state of Utah.

Canada was crossed by the Canadian Pacific in 1885; completion of the

railway was condition of British Columbia joining the Dominion of Canada,

and considerable land concessions were granted in virtually uninhabited

territory.

The crossing of Asia with the Trans-Siberian Railway was begun by the

Russians in 1890 and completed in 1902, except for ferry crossing Lake

Baikal. The difficult passage round the south end of the lake, with many

tunnels, was completed in 1905. Today more than half the route is

electrified. In 1863 the Orient Express ran from Paris for the first time

and eventually passengers were conveyed all the way to Istanbul

(Constantinople).

Rolling stock

In the early days, coaches were constructed entirely of wood, including the

frames. 1900, steel frames were commonplace; then coaches were

constructed entirely of steel and became very heavy. One American 85-foot

(26 m) coach with two six-wheel bogies weighed more than 80 tons. New

lightweight steel alloys and aluminium began

to be used; in the 1950s the Budd company in America was

building an 85-foot coach which weighed only 27 tons. The savings began

with the bogies, which were built without conventional springs, bolsters

and so on; with only two air springs on each four-wheel bogie, the new

design reduced the weight from 8 to 2,5 tons without loss f strength or

stability.

In the I880s, 'skyscraper' cars were two-storey wooden vans with

windows used as travelling dormitories for railway workers in the USA; they

had to be sawn down when the railways began to build tunnels through the

mountains. After World War II double-decker cars of mr compact design

were built, this time with plastic domes, so that passengers could enjoy

the spectacular scenery on the western lines, which pass through the Rocky

Mountains.

Lighting on coaches was by means of oil lamps at first; then gas lights

were used, and each coach carried cylinder f gas, which was dangerous in

the event of accident or derailment. Finally dynamos on each car, driven by

the axle, provided electricity, storage batteries being used for when the

car was standing. Heating on coaches was provided in the early days

by metal containers filled with hot water; then steam was piped from the

locomotive, an extra drain on the engine's power; nowadays heat as well as

light is provided electrically.

Sleeping accommodations were first made on the Cumberland Valley

Railroad in the United States in 1837. George Pullman's first cars ran on

the Chicago & Alton Railroad in 1859 and the Pullman Palace Car Company was

formed in 1867. The first Pullman cars operated in Britain in 1874, year

after the introduction of sleeping cars by two British railways. In Europe

in 1876 the International Sleeping Car Company was formed, but in the

meantime George Nagelmackers of Liege and an American, Col William D'Alton

nn, began operation between Paris and Viennain 1873.

Goods vans [freight cars] have developed according to the needs of the

various countries. On the North American continent, goods trains as long as

1,25 miles are run as far as 1000 miles unbroken, hauling bulk such as raw

materials and foodstuffs. Freight cars weighing 70 to 80 tons have two four

wheel bogies. In Britain, with denser population and closely adjacent

towns, large percentage of hauling is of small consignments of

manufactured goods, and the smallest goods vans of any country are used,

having four wheels and, up to 24,5 tons capacity. number of bogie wagons

are used for special purposes, such as carriages fr steel rails, tank cars

for chemicals and 50 ton brick wagons.

The earliest coupling system was links and buffers, which allowed jerky

stopping and starting. Rounded buffers brought snugly together by

adjustment of screw links with springs were an improvement. The buckeye

automatic coupling, long standard in North America, is now used in Britain.

The coupling resembles knuckle made of steel and extending horizontally;

joining utomtika11 with the coupling of the next r when pushed

together, it is released by pulling pin.

The first shipment of refrigerated goods was in 1851 when butter was

shipped from New York to Boston in wooden van packed with ice and

insulated with sawdust. The bulk of refrigerated goods were still carried

by rail in the USA in the, 1960s, despite mechanical refrigeration in motor

haulage; because of the greater first cost and maintenance cost of

mechanical refrigeration, rail refrigeration is still mostly

provided by vans with ice packed in end bunkers, four to six inches (10 to

15 cm) of insulation and fans to circulate the cool air.

Railways in wartime

The first war in which railwaysfigured prominently

was the American Civil War (1860-65), in which the Union

(North) was better able to organize andmake use of its railways than the

Confederacy (South). The war was marked by famous incident in which 4-4-

0 locomotive

called the General was hi-jacked by Southern agents.

The outbreak of World War 1 was caused in part by the

fact that the mobilization plans of the various countries, including the

use f railways and rolling stock, was planned to the last detail, except

that there were n provisions for stopping the plans once they had been put

into action until the armies were facing each other. In 1917 in the United

States, the lessons of the Civil War had been forgotten, and freight vans

were sent to their destination with n facilities for unloading, with the

result that the railways were briefly taken over by the government for the

only time in that nation's history.

In World War 2, by contrast, the American railways performed

magnificently, moving 2,5 times the level of freight in 1944 as in 1938,

with minimal increase in equipment, and supplying more than 300,000

employees to the armed forces in various capacities. In combat areas, and

in later conflicts such as the Korean war, it proved difficult to disrupt

an enemy's rail system effectively; pinpoint bombing was difficult,

saturation bombing was expensive and in any case railways were quickly and

easily repaired.

State railways

State intervention began in England withpublic demand for safety

regulation which resulted in Lord

Seymour's Act in 1840; the previously mentioned Railway

Gauges Act followed in 1846. Ever since, the railways havebeen recognized

as one of the most important of nationalresources in each country.

In France, from 1851 onwards concessions were granted for a planned

regional system for which the Government provided ways and works and the

companies provided track and roiling stock; there was provision for the

gradual taking over of the lines by the State, and the Societe Nationale

des Chemins de Fer Francais (SNCF) was formed in 1937 as company in which

the State owns 51% of the capital and theompanies 49%.

The Belgian Railways were planned by the State from the outset in 1835.

The Prussian State Railways began in 1850; b the end of the year 54 miles

(87 km) were open. Italian and Netherlands railways began in 1839; Italy

nationalized her railways in 1905-07 and the Netherlands in the period 1920-

38. In Britain the main railways were nationalized from 1 January 1948; the

usual European pattern is that the State owns the main lines and minor

railways are privately owned or operated by local authorities.

In the United States, between the Civil War and World Wr 1 the

railways, along with all the other important inndustries, experienced

phenomenal growth as the country developed. There were rate wars and

financial piracy during period of growth when industrialists were more

powerful than the national government, and finally the Interstate Commerce

Act was passed in l887 in order to regulate the railways, which had near

monopoly of transport. After World War 2 the railways were allowed to

deteriorate, as private car ownership became almost universal and public

money was spent on an interstate highway system making motorway haulage

profitable, despite the fact that railways are many times as efficient at

moving freight and passengers. In the USA, nationalization of railways

would probably require an amendment to the Constitution, but since 1971

government effort has been made to save the nearly defunct passenger

service. On 1 May of that year Amtrack was formed by the National Railroad

Passenger Corporation to operate skeleton service of 180 passenger trains

nationwide, serving 29 cities designated by the government as those

requiring train service. The Amtrack service has been heavily used, but

not adequately funded by Congress, so that bookings,

especially for sleeper-car service, must be made far in

advance.

The locomotive

Few machines in the machine age have inspired so much affection as

railway locomotives in their 170 years of operation. Railways were

constructed in the sixteenth century, but the wagons were drawn by muscle

power until l804. In that year an engine built by Richard Trevithick worked

on the Penydarren Tramroad in South Wales. It broke some cast iron

tramplates, but it demonstrated that steam could be used for haulage, that

steam generation could be stimulated by turning the exhaust steam up the

chimney to draw up the fire, and that smooth wheels on smooth rails could

transmit motive power.

Steam locomotives

The steam locomotive is robust and

simple machine. Steam is admitted to cylinder and by

expanding pushes the piston to the other end; on the return stroke port

opens to clear the cylinder of the now expanded steam. By means of

mechanical coupling, the travel of the piston turns the drive wheels of the

locomotive.

Trevithick's engine was put to work as stationary engine at

Penydarren. During the following twenty-five years, limited number of

steam locomotives enjoyed success on colliery railways, fostered by the

soaring cost of horse fodder towards the end of the Napoleonic wars. The

cast iron plateways, which were L-shaped to guide the wagon wheels, were

not strong enough to withstand the weight of steam locomotives, and were

soon replaced by smooth rails and flanged wheels on the rolling stock.

John Blenkinsop built several locomotives for collieries, which ran on

smooth rails but transmitted power from toothed wheel to rack which ran

alongside the running rails. William Hedley was building smooth-whilled

locomotives which ran on plateways, including the first to have the popular

nickname Puffing Billy.

In 1814 George Stephenson began building for smooth rails at

Killingworth, synthesizing the experience of the earlier designers. Until

this time nearly all machines had the cylinders partly immersed in the

boiler and usually vertical. In 1815 Stephenson and Losh patented the idea

of direct drive from the cylinders by means of cranks on the drive wheels

instead of through gear wheels, which imparted jerky motion, especially

when wear occurred on the coarse gears. Direct drive allowed simplified

layout and gave greater freedom to designers.

In 1825 only 18 steam locomotives were doing useful work. One of the

first commercial railways, the Liverpool & Manchester, was being built, and

the directors had still not decided between locomotives and bl haulage,

with railside steam engines pulling the cables. They organized

competition which was won by Stephenson in 1829, with his famous engine,

the Rocket, now in London's Science Museum.

Locomotive boilers had already evolved from simple

flue to return-flue type, and then to tubular design, in which nest

of fire tubes, giving more heating surface, ran from the firebox tube-plate

to similar tube-plate at the smokebox end. In the smokebox the exhaust

steam from the cylinders created blast on its way to the chimney which

kept the fire up when the engine was moving. When the locomotive was

stationary blower was used, creating blast from ring f perforated

pipe into which steam was directed. further development, the multitubular

boiler, was patented by Henry Booth, treasurer of the Liverpool &

Manchester, in 1827. It was incorporated by Stephenson in the Rocket, after

much trial and error in making the ferrules of the copper tubes to give

water-tight joints in the tube

plates.

After 1830 the steam locomotive assumed its familiar form, with the

cylinders level or slightly inclined at the smokebox end and the fireman's

stand at the firebox end.

As soon as the cylinders and axles were n longer fixed in or under the

boiler itself, it became necessary to provide frame to hold the various

components together. The bar frame was used on the early British

locomotives and exported to America; the Americans kept the bar-frame

design, which evolved from wrought iron to cast steel construction, with

the cylinders mounted outside the frame. The bar frame was superseded in

Britain by the plate frame, with cylinders inside the frame, spring

suspension (coil or laminated) for the frames and axleboxes (lubricated

bearings) to hold the

axles.

As British railways nearly all produced their own designs, great many

characteristic types developed. Some designs with cylinders inside the

frame transmitted the motion to crank-shaped axles rather than to eccentric

pivots on the outside of the drive wheels; there were also compound

locomotives, with the steam passing from first cylinder or cylinders to

another set of larger ones.

When steel came into use for building boilers after 1860, higher

operating pressures became possible. By the end of the nineteenth century

175 psi (12 bar) was common, with 200 psi (13.8 bar) for compound

locomotives. This rose to 250 psi (17.2 bar) later in the steam era. (By

contrast, Stephenson's Rocket only developed 50 psi, 3.4 bar.) In the l890s

express engines had cylinders up to 20 inches (51 cm) in diameter with 26

inch (66 cm) stroke. Later diameters increased to 32 inches (81 cm) in

places like the USA, where there was more room, and locomotives and rolling

stock in general were built larger.

Supplies of fuel and water were carried on separate tender, pulled

behind the locomotive. The first tank engine carrying its own supplies,

appeared tn the I830s; on the continent of Europe they were. confusingly

called tender engines. Separate tenders continued to be common because they

made possible much longer runs. While the fireman stoked the firebox, the

boiler had to be replenished with water by some means under his control;

early engines had pumps running off the axle, but there was always the

difficulty that the engine had to be running. The injector was invented in

1859. Steam from the boiler (or latterly, exhaus steam) went through

cone-shaped jet and lifted the water into the boiler against the greater

pressure there through energy imparted in condensation. clack (non-return

valve)

retained the steam in the boiler.

Early locomotives burned wood in America, but coal in Britain. As

British railway Acts began to include penalties for emission of dirty black

smoke, many engines were built after 1829 to burn coke. Under Matthetty

Kirtley on the Midland Railway the brick arch in the firebox and deflector

plates were developed to direct the hot gases from the coal to pass over

the flames, so that relatively clean blast came out of

the chimney and the cheaper fuel could be burnt. After 1860 this simple

expedient was univers11 adopted. Fireboxes were protected by being

surrounded with water jacket; stays about four inches (10 cm) apart

supported the inner firebox from the outer.

Steam was distributed to the pistons by means of valves. The valve gear

provided for the valves to uncover the ports at different parts of the

stroke, so varying the cut-off to provide for expansion of steam already

admitted to the cylinders and to give lead or cushioning by letting the

steam in about 0.8 inch (3 mm) from the end of the stroke to begin the

reciprocating motion again. The valve gear also provided for reversing by

admitting steam to the opposite side of the piston.

Long-lap or long-travel valves gave wide-open ports for the exhaust

even when early cut-ff was used, whereas with short travel at early cut-

off, exhaust and emission openings became smaller so that at speeds of over

60 mph (96 kph) one-third of the ehergy of the steam was expanded just

getting in and out of the cylinder. This elementary fact was not

universal1y

accepted until about 1925 because it was felt that too much extra wear

would occur with long-travel valve layouts.

Valv operation on most early British locomotives was by Stephenson

link motion, dependent on two eccentrics on the driving 1 connected by

rods to the top and bottom of an expansion link. block in the link,

connected to the reversing lever under the control of the driver, imparted

the reciprocating motion t the valve spindle. With the block at the top of

the link, the engine would be in full forward gear and steam would be

admitted to the cylinder for perhaps 75% of the stoke. As the engine was

notched up by moving the lever back over its serrations (like the handbrake

lever of r), the cut-off was shortened; in mid-gear there was no steam

admission to the cylinder and with the block at the bottom of the link the

engine was in full reverse.

Walschaert's valvegear, invented in 1844 and in general use after 1890,

allowed more precise adjustment and easier operation for the driver. An

eccentric rod worked from return crank by the driving axle operated the

expansion link; the block imparted the movement to the valve spindle, but

the movement was modified by combination lever from crosshead on the

piston rod.

Steam was collected as dry as possible along the top of the boiler in

perforated pipe, or from point above the boiler in dome, and passed to

regulator which controlled its distribution. The most spectacular

development of steam locomotives for heavy haulage and high speed runs was

the introduction of superheating. return tube, taking the steam back

towards the firebox and forward again to header at the front end of the

boiler through an enlarged flue-tube, was invented by Wilhelm Schmidt of

Cassel, and modified by other designers. The first use of such equipment in

Britain was in 1906 and immediately the savings in fuel and especially

water were remarkable. Steam at 175 psi, for example, was generated

'saturated' at 371'F (188'); by adding 200'F (93'C) of superheat, the

steam expanded much more readily in the cylinders, so that twentieth-

century locomotives were able to work at high speeds at cut-offs as short

as 15%. Steel tyres, glass fibre boiler lagging, long-lap piston valves,

direct steam passage and superheating all contributed to the last

phase of steam locomotive performance.

Steam from the boiler was also for other purposes.

Steam sanding was introduced for traction in 1887 on th

Midland Railway, to improve adhesion better than gravity

sanding, which often blew away. Continuous brakes were

operated by vacuum created on the engine or by mpressed air supplied by

steam pump. Steam heat was piped to the carriages, arid steam dynamos

[generators] provided electric light.

Steam locomotives are classified according to the number of wheels.

Except for small engines used in marshalling rds, all modern steam

locomotives had leading wheels on a pivoted bogie or truck to help guide

them around urves. The trailing wheels helped carry the weight of the

firebox. For many years the 'American standard' locomotive was a 4-4-0,

having four leading wheels, four driving wheels and no trailing wheels. The

famous Civil War locomotive, the General, was 4-4-0, as was the New York

Central Engine No 999, which set speed record 1 112.5 mph (181 kph) in

1893. Later, common freight locomotive configuration was the Mikado type,

2-8-2.

Continental classification counts axles instead f wheels, and

another modification gives drive wheels letter of the alphabet, so the 2-

8-2 would be 1-4-1 in France and IDI in Germany.

The largest steam locomotives were articulated, with two sets of drive

wheels and cylinders using common boiler. The sets f drive wheels were

separated by pivot; otherwise such large engine could not have

negotiated curves. The largest ever built was the Union Pacific Big o,

4-8-8-4, used to haul freight in the mountains of the western United

States. Even though it was articulated it could not run on sharp curves. It

weighed nearly 600 tons, compared to less than five tons for Stephenson's

Rocket.

Steam engines could take lot of hard use, but they are now obsolete,

replaced by electric and especially diesel-electric locomotives. Because of

heat losses and incomplete combustion of fuel, their thermal efficinc was

rarely more than 6%.

Diesel locomotives

Diesel locomotives are most commonly diesel-electric. diesel engine

drives dynamo [generator] which provides power for electric motors which

turn the

drive wheels, usually through pinion gear driving ring gear on the

axle. The first diesel-electric propelled rail car was built in 1913, and

after World War 2 they replaced steam engines completely, except where

electrification of railways is economical.

Diesel locomotives have several advantages over steam engines. They are

instantly ready for service, and can be shut down completely for short

eriods, whereas it takes some time to heat the water in the steam engine,

especially in cold weather, and the fire must be kept up while the steam

engine is on standby. The diesel can go further without servicing, as it

consumes n water; its thermal efficiency is four times as high, which

means further savings of fuel. Acceleration and

high-speed running are smoother with diesel, which means less wear on

rails and roadbed. The economic reasons for turning to diesels were

overwhelming after the war, especially in North America, where the railways

were in direct competition with road haulage over very long distances.

Electric traction

The first electric-powered rail car was built in 1834, but early

electric cars were battery powered, and the batteries were heavy and

required frequent recharging. d 1tri trains are not self-contained,

which means that they get their power from overhead wires or from third

rail. The power for the traction motors is collected from the third rail

by means of shoe or from the overhead wires by pantograph.

Electric trains are the most nomical to operate,

provided that traffic is heavy enough to repay electrification of the

railway. Where trains run less frecuentl over long distances the cost of

electrification is prohibitive. DC systems have been used as opposed to

because lighter traction motors can be used, but this requires power

substations with rectifiers to convert the power to D from the of the

commercial mains. (High voltage DC power is difficult to transmit over long

distances.) The latest development

of electric trains has been the installation of rectifiers in the cars

themselves and the use of the same frequency as the commercial mains (50

Hz in Europe, 60 Hz in North America),which means that fewer substations

are necessary.

Railway systems

The foundation of modern railway system is track which does not

deteriorate under stress of traffic. Standard track in Britain comprises a

flat-bottom section of rail weighing 110 lb per yard (54 kg per metre)

carried on 2112 cross-sleepers per mile (1312 per km). Originally creosote-

impregnated wood sleepers [cross-ties] were used, but they are now made of

post-stressed concrete. This enables the rail to transmit the

pressure, perhaps as much as 20 tons/in2(3150 kg/cm2) fromthe small area of

contact with the wheel, to the ground below the track formation where it is

reduced through the sole plate and the sleeper to about 400 psi (28

kg/cm2). In soft ground, thick polyethylene sheets are generally placed

under the ballast to prevent pumping of slurry under the weight of trains.

The rails are tilted towards one another on 1 in 20 sl. Steel

rails tnay last 15 or 20 years in traffic, but to prolong the undisturbed

life of track still longer, experiments have been carried out with paved

concrete track (PAC) laid by slip paver similar to concrete highway

construction in reinforced concrete. The foundations, if new, are similar

to those for

motorway. If on the other'hand, existing railway formation is to be used,

the old ballast is s1d with bitumen emulsion before applying the

concrete which carries the track fastenings glued in with cement grout or

epoxy resin. The track is made resilient by use of rubber-bonded cork

packings 0.4 inch (10 mm) thick. British Railways purchases rails in 60 ft

(18.3 m) lengths which are shop-welded into 600 ft (183 m) lengths and then

welded on site into continuous welded track with pressure-relief points at

intervals of several miles. The contfnuotls welded rails make for

steadier and less noisy ride for the passenger and reduce the tractive

effort.

Signalling

The second important factor contributing to safe rail travel is the

system of signalling. Originally railways relied on the time interval to

ensure the safety of a succession of trains, but the defects rapidly

manifested themselves, and a space interval, or the block system, was

adopted, although it was not enforced legally on British passenger lines

until the

Regulation of Railways Act of 1889. Semaphore signals

became universally adopted on running lines and the interlocking f points

[switches] and signals (usually accomplished mechanically by tappets) to

prevent conflicting movements being signalled was also requirement of the

1889 t. Lock-and-block signalling, which ensured safe sequence of

movements by electric checks, was introduced on the London, Chatham and

Dover Railway in 1875.

Track circuiting, by which the presence of train is detected by an

electric current passing from one rail to another through the wheels and

axles, dates from 1870 when William Robinson applied it in the United

States. In England the Great Eastern Railway introduced power operation of

points and signals at Spitaifields goods yard in 1899, and three years

later track-circuit operation of powered signals was in operation on 30

miles (48 km) of the London and Sout Western Railway main line.

Day colour light signals, controlled automatically by the trains

through track circuits, were installed on the Liverpool Overhead Railway in

1920 and four-aspect day colour lights (red, yellow, double yellow and

green) were provided on Southern Railway routes from 1926 onwards. These

enable drivers of high-speed trains to have warning two block sections

ahead of possible need to stop. With track circuiting it became usual to

show the presence f vehicles on track diagram in the signal cabin which

allowed routes to be controlled remotely by means of electric relays.

Today, panel

operation of considerable stretches of railway is common-l; at Rugby,

for instance, signalman can control the points at station 44 miles (71

km) away, and the signalbox at London Bridge controls movements on the

busiest 150 track-miles of British Rail. By the end of the I980s, the 1500

miles (241 km) of the Southern Region of British Rail are to be controlled

from 13 signalboxes. In modern panel installations the trains are not only

shown on the track diagram as they move from one section to another, but

the train identification number appears electronically in each section.

mputer-assisted train description, automatic train rporting and, at

stations such as London Bridge, operation of platform indicators, is now

usual.

Whether points are operated manually or by an electric point motor,

they have to be prevented from moving while a train is passing over them

and facing points have to be locked, nd roved t lkd (r 'detected'

) before th relevant signal can permit train movement. The blades of the

points have to be closed accurately (.16 inch or 0.4 cm is the maximum

tolerance) so as to avert any possibility of wheel flange splitting the

point and leading to derailment.

Other signalling developments of recent years include completely

automatic operation of simple point layouts, such as the double crossover

at the Bank terminus of the British Rails's Waterloo and City underground

railway. On London ransport's underground system plastic roll operates

junctions according to the timetable by means of coded punched holes, and

on the Victoria Line trains are operated automatically once the driver has

pressed two buttons to indicate his readiness to start. also acts as the

guard, controlling the opening f th doors, closed circuit television

giving him view along the train. The trains are controlled (for

acceleration and braking) by coded impulses transmitted through the running

rails to induction coils mounted on the front of the train. The absence of

code impulses cuts off the current and applies the brakes; driving and

speed control is covered by command spots in which frequency of 100 Hz

corresponds to one mile per hour (1.6 km/h), and l5 kHz

shuts off the current. Brake applications are so controlled that trains

stop smoothly and with great accuracy at the desired place on platforms.

Occupation of the track circuit ahead by train automatically stops the

following train, which cannot receive code.

On ritish main lines an automatic warning system is being installed by

which the driver receives in his b visual and audible warning of

passing distant signal at caution; if he does not acknowledge the warning

the brakes are applied automatically. This is accomplished by magnetic

induction between magnetic unit placed in the track and actuated

according to the signal aspect, and unit on the train.

Train control

In England train control began in l909 on the Midland Railway,

particularly to expedite the movement f coal trains and to see that guards

and enginemen were

relieved at the end of their shift and were not called upon to work

excessive overtime. Comprehensive train control systems, depending on

complete diagrams of the track layout and records of the position of

engines, crews and rolling stock, were developed for the whole of Britain,

the Southern Railway being the last to adopt it during World War 2, having

hitherto given great deal of responsibility to signalmen for the

regulation of trains. Refinements f control include advance traffic

information(ATI) in which information is passed from yard to yard by telex

giving types of wagon, wagon number, route code, particulars f the load,

destination

station and consignee. In l972 British Rail decided to

adopt computerized freight information and traffic control system known

as TOPS (total operations processing system) which was developed over eight

years by the Southern Pacific company in the USA.

Although great deal of rail 1rffi in Britain is handled by block

trains from point of origin to destination, about onefifth of the

originating tonnage is less than a train-load. This means that wagons must

be sorted on their journey. In Britain there are about 600 terminal points

on a 12,000 mile network whitch is served by over 2500 freight trains made

up of varying assortments of 249,000 wagons and 3972 locomotives, of witch

333 are electric. This requires the speed of calculation and the

information storage and classification capacity of the modern computer,

whitch has to be linked to points dealing with or generating traffic

troughout the system.The computer input, witch is by punched cards, covers

details of loading or unloading of wagons and their movements in trains,

the composition of trains and their departures from and arrivals at yards

,and the whereabouts of locomotives. The computer output includes

information on the balanse of locomotives at depots and yards, with

particulars of when maintenanse examinations are due, the numbers of

empty and loaded wagons, with aggregate weight and brake forse, and wheder

their movement is on time, the location of empty wagons and a forecast of

those that will become available, and the numbers of trains at any

location, with collective train weigts and individual details of the

component wagons.

A closer check on what is happening troughoud the

system is thus provided, with the position of consignments in transit,

delays in movement, delays in unloading wagons by customers, and the

capasity of the system to handle future traffic among the information

readily available. The computer has a built-in self-check on wrong input

information.

Freight handling

The merry-go-round system enables coal for power

stations to be loaded into hopper wagons at a colliery

without the train being stopped, and at the power station the train is

hauled round a loop at less than 2mph (3.2 km/h), a trigger devise

automatically unloading the wagons without the train being stopped. The

arrangements also provide for automatic weighing of the loads. Other bulk

loads can be dealt with in the same way.

Bulk powders, including cement, can be loaded and discharged

pneumatically, using either ri1 wagons or containers. Iron ore is carried

in 100 ton gross wagons (72 tons of payload) whose coupling gear is

designed to swivel, so that wagons can be turned upside down for discharge

without uncoupling from their train. Special vans take palletized loads of

miscellaneous merchandise or such products as fertilizer, the van doors

being designed so that all parts of the interior can be reached by fork-

lift truck.

British railway companies began building their stocks of containers in

1927, and by 1950 they had the largest stock of large containers in Western

Europe. In 1962 British Rail decided to use International Standards

Organisation sizes, 8 ft (2,4 m) wide by 8 ft high and 1, 20, 30 and 40 ft

(3.1, 6.1, 9.2 and 12.2 m) long. The 'Freightliner' service of container

trains uses 62.5 ft (19.1 m) flat wagons with air-operated disc brakes in

sets f five and was inaugurated in 1965. At depots

'Drott' pneumatic-tyred cranes were at first provided but rail-mounted

Goliath cranes are now provided.

Cars are handled by double-tier wagons. The British car industry is

big user of 'omn' trains, which are operated for single customer.

Both Ford and Chrysler use them to exchange parts between specialist

factories nd the railway thus becomes an extension of factory transport.

Company trains frequent1 consist of wagons owned by the trader; there are

about 20,000 on British railways, the oil industry, for example, providing

most f the tanks it needs to carry 21 million tons of petroleum products

by rail each year despite

competition from pipelines.

Gravel dredged from the shallow seas is another developing source of

rail traffic. It is moved in 76 ton lots by 100 ton gross hopper wagons and

is either discharged on to belt conveyers to go into the storage bins at

the destination or, in another system, it is unloaded by truck-mounted

discharging machines.

Cryogenic (very low temperature) products are also transported by rail

in high capacity insulated wagons. Such products include liquid oxygen and

liquid nitrogen which are taken from central plant to strategically-

placed railheads where the liquefied gas is transferred to road tankers for

the journey to its ultimate destination.

Switchyards

Groups of sorting sidings, in which wagons [freight cars] can be

arranged in order s that they can be

detached from the train at their destination with the least possible delay,

are called marshalling yards in Britain and classification yards or

switchyards in North America. The work is done by small locomotives called

switchers or shunters, which move 'cuts' of trains from one siding to

another until the desired order is achieved.

As railways became more complicated in their system

layouts in the nineteenth century, the scope and volume of necessary

sorting became greater, and means of reducing the time and labour involved

were sought. ( 1930, for every 100 miles that freight trains were run in

Britain there were 75 miles of shunting.) The sorting of coal wagons for

return to the collieries had been assisted by gravity as early as 1859, in

the sidings at Tyne dock on the North Eastern Railway; in 1873 the London &

North Western Railway sorted traffic to and from Liverpool on the Edge Hill

'grid irons': groups of

sidings laid out on the slope of hill where gravity provided the motive

power, the steepest gradient being 1 in 60 (one foot of elevation in sixty

feet of siding). Chain drags were used for braking he wagons. shunter

uncoupled the wagons in 'cuts' for the various destinations and each cut

was turned into the appropriate siding. Some gravity yards relied on code

of whistles to advise the signalman what 'road' (siding) was required.

In the late nineteenth century the hump yard was introduced to provide

gravity where there was n natural slope of the land. In this the trains

were pushed up an artificial mound with gradient of perhaps 1 in 80 and

the cuts were 'humped' down somewhat steeper gradient on the other side.

The separate cuts would roll down the selected siding in the fan or

'balloon' of sidings, which would nd in slight upward slope to assist in

the stopping of the wagons. The main means of stopping the wagons, however,

were railwaymen called shunters who had to run alongside the wagons and

apply the brakes at the right time. This was dangerous and required

excessive manpower.

Such yards rd all over North America and north-east England and

began to be adopted elsewhere in England. Much ingenuity was devoted to

means of stopping the wagons; German firm, Frohlich, came up with

hydraulically operated retarder which clasped the wheel of the wagon as it

went past, to slow it down to the amount the operator throught nssar.

An entirely new concept came with Whitemoor yard at

March, near Cambridge, opened by the London & North

Eastern Railway in l929 to concentrate traffic to and from East Anglian

destinations. When trains arrived in one of ten reception sidings shunter

examined the wagon labels and prepared 'cut card' showing how the train

should be sorted into sidings. This was sent to the control tower by

pneumatic tube; there the points [switches] for the forty sorted sidings

were preset in accordance with the cut card; information for several trains

could be stored in simple pin and drum device.

The hump was approached by grade of 1 in 80. On the far side was

short stretch of 1 in 18 to accelerate the wagons, followed by 70 yards {64

m) at 1 in 60 where the tracks divided into four, each equipped with

Frohlich retarder. Then the four tracks spread out to four balloons of ten

tracks each, comprising 95 yards (87 m) of level track followed by 233

yards (213 m) falling at 1 in 200, with the remaining 380 yards

(348 m) level. The points were moved in the predetermined sequence by

track circuits actuated by the wagons, but the operators had to estimate

the effects on wagon speed of the retarders, depending to degree on

whether the retarders were grease or oil lubricated.

Pushed by an 0-8-0 small-wheeled shunting engine at 1.5 to 2 mph (2.5

to 3 km/h), train of 70 wagons could be sorted in seven minutes. The yard

had throughput of about 4000 wagons day. The sorting sidings were

allocated: number one for Bury St Edmunds, two for Ipswich, and s forth.

Number 31 was for wagons with tyre fastenings which might be ripped off by

retarders, which were not used on that siding. Sidings 32 t 40 were for

traffic to be dropped at wayside stations; for these sidings there was an

additional hump for sorting these wagons in station order. Apart from the

sorting

sidings, there were an engine road, brake van road,

'cripple' road for wagons needing repair, and transfer road to three

sidings serving tranship shed, where small shipments not filling entire

wagons could be sorted.

British Rail built series of yards at strategic points; the yards

usually had two stages of retarders, latterly electropneumatically

operated, to control wagon speed. In lateryards electronic equipment was

used to measure the weight of each wagon and estimate its

rolling resistance. By feeding this information into computer, suitable

speed for the wagon could be determined and the retarder

operatedautomatically to give the desired amount of braking. These

predictions did not always prove reliable.

At Tinsley, opened in l965, with eleven reception roads and 53 sorting

sidings in eight balloons, the Dowty wagon speed control system was

installed. The Dowty system uses many small units (20,000 at Tinsley)

comprising hydraulic rams on the inside of the rail, less than wagon

length apart. The flange of the wheel depresses the ram, which returns

after the wheel has passed. speed-sensing device determines whether the

wagon is moving too fast from thehump; if the speed is too fast the ram

automatically has retarding action.

Certain of the units are booster-retarders; if the wagon is moving too

slowly, hydraulic supply enablesthe ram to accelerate the wagon. There

are 25 secondary sorting

sidings at Tinsley to which wagons are sent over

secondary hump by the booster-retarders. If individual unitsfail the rams

can be replaced.

An automatic telephone exchange links ll the traffic and

administrative offices in the yard with the railway controlffi,

Sheffield Midland Station and the local steelworks(principal source of

traffic). Two-w loudspeaker systems are available through all the

principal points in the yard, and radio telephone equipment is used t

speak to enginemen. Fitters maintaining the retarders have walki-talkie

equipment.

The information from shunters about the cuts and how many wagons in each,

together with destination, is

conveyed by special data transmission equipment, punched tape being

produced to feed into the point control system for each train over the

hump.

As British Railways have departed from the wagon-load system there is

less employment for marshalling yards. Freightliner services, block coal

trains from colliery direct to power stations or to coal concentration

depots, 'company' trains and other specialized freight traffic developments

obviate the need for visiting marshalIing yards. Other factors are

competition from motor transport, closing of wayside freight depots and of

many small coal yards.

Modern passenger service

In Britain network of city tocity services operates at speeds of up

to 100 mph (161 km/h) and at regular hourly intervals, or 30 minute

intervals on such routes as London to Birmingham. On some lines the speed

is soon to be raised to 125 mph (201 km/h)with high speed diesel trains

whos prototype has been shown to be

capable of 143 mph (230 km h). With the advanced passenger train (APT) now

under development, speeds of 150 mph (241 km/h) are envisaged. The Italians

are developing system capable of speeds approaching 200 mph (320 km/h)

while the Japanese and the French already operate passenger trains at

speeds of about 150mph (241 km/h).

The APT will be powered either by electric motors or by gas turbines,

and it can use existing track because of its pendulum suspension which

enables it to heel over when travelling round curves. With stock hauled by

conventional locomotive, the London to Glasgow electric service holds the

European record for frequency speed over long distance. When the APT is

in service, it is expected that the London to Glasgow journey time of five

hours will be reduced to 2.5 hours.

In Europe number of combined activities organized

through the International Union af Railways included the

Trans-Europe-Express (TEE) network of high-speed passenger trains,

similar freight service, and network of railway-ssociated road services

marketed as Europabus.

Mountain railways

Cable transport has always been associated with hills and mountains. In

the late 1700s and early 1800s the wagonways used for moving coal from

mines to river or sea ports were hauled by cable up and down inclined

tracks. Stationary steam engines built near the top of the incline drove

the cables, which were passed around drum connected to the steam engine

and were carried on rollers along the track. Sometimes cable-worked

wagonways were self-acting if loaded wagons worked downhill, fr they could

pull up the lighter empty wagons. Even after George Stephenson perfected

the travelling steam locomotive to work the early passenger railways of the

1820s and 1830s cable haulage was sometimes used to help trains climb the

steeper gradients, and cable working continued to be used for many steeply-

graded industrial wagonways throughout the 1800s. Today few cable-worked

inclines survive at industrial sites and for such unique forms of transport

as the San Francisco tramway [streetcar] system.

Funiculars

The first true mountain railways using steam

locomotives running on 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 number of mountain slopes. Most worked

on 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 few cases, usually only 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 ar 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 t 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

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 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 r

underframe act on the rails as soon as the cable becomes slack. When

cable is due for renewal the opportunity is taken to test the braking

system by cutting the cable

nd 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 mr than about 5 to 1 mph (8 to 16 km/h). Some

lines are divided 1nt sections with pairs f 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 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 steel ladder, and the Abt and Strub types use 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 n steeper than 1 in

4 (25 per cent). One line in Switzerland up Mount Pilatus has 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 nd survive

in regular service on only one line in Switzerland, on Britain's only rack

line up Snowdon in North Wales, and handful of others. Most of the

remainder have been electrified or 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

four-wheel rail vehicle. The world's first street ri1w, or tramway, was

built in New York in 1832; it was mile (1,6 km) long and known as the New

York & Harlem Railroad. There were two horse-drawn rs, 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 f 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 cit governments.

The advantage of the horse tram over the horse bus was that steel

wheels on steel rails gave smoother ride and less friction. horse could

haul on rails twice as much weight s on 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 f these rn from rbl Arch for short distance along the

Bayswater Road. The lines used type of step rail which stood up from the

road surface and interfered with other traffic, so they were taken up

within year. London's more permanent tramways began running in 1870, but

Liverpool had 1in working in November 1869. Rails which could be laid

flush with the road surface were used for these lines.

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 t th weight of locomotive.

The solution to this problem was found in the cable r. 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 slot in the roadway to grip the cable, and the car itself weighed

n more than 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 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;

converted horse r with batteries under the seats and single electric

motor was tried in London in 1883, but the experiment lasted only one day.

Compressed air driven trams, the invention of jr 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 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 power station to be fed to tramcar in motion.

The first useful system emp1d small two-wheel carriage running on top

of an overhead wire and connected t the tramcar by cable. The circuit

was completed via wheels and the running rails. tram route on this

system was working in Montgomery, Alabama, as early as 1886. The cohverted

horse cars had motor mounted on one of the end platforms with chain drive

to one axle. Shortly afterwards, in the USA and Germany there wer trials

on similar principle but using four-wheel overhead carriage known as

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 lectrical working. There he perfected the swivel trolley

1 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

ltrified 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

single driver and one or two conductors, Double-deck cars could haul

trailers in peak hours and for time such trailers were common sight in

London.

The two main power collection systems were from

overhead wires, as already described though modern

tramways often use pantograph collecting devi 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 moving cable there are current supply

rails in the conduit. The tram is fitted with device called plough

which passes down into the conduit. On each side of the plough is contact

shoe, one of which presses against each of the rails. Such system was

used in inner London, in New York and Washington DC, and in European

cities.

Trams were driven through controller on each platform. In single-

motor car, this allowed power to pass through resistariceas well as the

motor, the amount f resistanc being reduced in steps by moving handle

as desired, to feed more power to the motor. In two-motor cars much more

economical ntrol was used. When starting, the two motors were nnctd

in series, so that each motor received power in turn in effect, each got

half th power available, the amount of power again being regulated b

resistances. As speed rose

the controller was 'notched up' to further set of steps in which the

motors were connected in parallel so that each reived current direct from

the power source instead o sharing it. The ntrllr could also be moved

to further set of notches which gave degrees of 1trical braking,

achieved by connecting the motors so that they acted as generators, the

power generated being absorbed by the resistances. n merican tramcar

revival in the I930s resulted in the design of new tramcar known as the

type after the Electric Railway Presidents nfrnce 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 tram route

is fixed, bus route can be changed as the need for it changes. The

inability of tram to draw in to the kerb to discharge and take on

passengers was 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, r trackless tram. The first crude

versions were tried out in Germany and the USA in the early 1880s. The

current llection system needed two cables and collector arms, sine there

were n rails. 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. Londons first trolleybus, introduced in 1931,

was based on 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 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

ndemned trams in most parts f 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 f two. They have

been experimentally built for more than 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 pony or bicycle.

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

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. similar line was built to carry bricks to River Lea barges from

brickworks at Cheshunt in 1825. The cars, pulled by horse and tow r,

were in two parts, one on each side of the rail, hanging from a framework

which carried the wheels.

Later, monorails on this principle were built by Frenchman, F M T

Lartigue. put his single rail on top of series of triangular trestles

with their bases on the ground; he also put guide rail on each side of

the trestles on which ran horizontal wheels attached to the cars. The cars

thus had both vertical and sideways support nd were suitable for higher

speeds than the earlier type.

steam-operated line on this principle was built in Syria in 1869 by J

L Hadden. The locomotive had two vertical boilers, n on each side f the

pannier-type vehicle.

An electric Lartigue line was opened in central France in 1894, and

there were proposals to build network of them on Long Island in the USA,

radiating from Brooklyn. There was demonstration in London in 1886 on

short line, trains being hauled by two-boiler Mallet steam locomotive.

This had two double-flanged driving wheels running on the raised centre

rail and guiding wheels running on tracks on each side of the trestle.

Trains were switched from one track to anothe

by moving whole section of track sideways to line up with another

section. In 1888 line on this principle was laid in Ireland from Listowel

to llybunion, distance of 9,5 miles; it ran until 1924. There were

three locomotives, each with two horizontal boilers hanging one each side

of the centre wheels. They were capable of 27 mph (43.5 km/h); the

carriages wr built with the lower parts in two sections, between which

were the wheels.

The Lartigue design was adapted further by F B Behr, who built three-

mil electric line near Brussels in l897. The mnri1 itself was again at

the top of n '' shaped trestle, but there were two balancing and guiding

rails on each side, s that although the weight of the r was carried by

one rail, ther were really five rails in ll. The r weighed 55 tons and

had two four-wheeled bogies (that is, four wheels in line n each bogie).

It was built in England and had motors putting

out total of 600 horsepower. The r ran at 83 mph (134 km/h) and was

said to have reached 100 mph (161 km/h) in private trials. It was

extensively tested by representatives of the Belgian, French and Russian

governments, and Behr came near to success in achieving wide-scale

application of his design.

An attempt to build monorail with one rail laid on the ground in

order to save space led to the use of gyroscope to keep the train

upright. gyroscope is rapidly spinning flywheel which resists any

attempt to alter the angle of the axis on which it spins.

true monorail, running on single rail, was built for military

purposes by Louis Brennan, an Irishman who also invented steerable

torpedo. Brennan applied for monorail patents in 1903, exhibited large

working model in 1907 and full-size 22-ton car in 1909 10. It was held

upright by two gyroscopes, spinning in opposite directions, and carried 50

people or ten tons of freight.

similar r carrying only six passengers and driver was

demonstrated in Berlin in 1909 by August Scherl, who had taken out patent

in 1908 and later m to an agreement with Brennan to use his patents

also. Both systems allowed the cars to lean over, like bicycles, on curves.

Scherl's was an electric car; Brennan's was powered by an internal

combustion engine rather than steam so as not to show any tell-tale smoke

when used by the military. steam-driven gyroscopic system was designed by

Peter Schilovsky, Russian nobleman. This reached only the model stage; it

was held upright by single steam-driven gyroscope placed in the tender.

The disadvantage with gyroscopic monorail systems was that they

required power to drive the gyroscope to keep the train upright even when

it was not moving.

Systems were built which ran on single rails on the ground but used

guide rail at the top to keep the train upright. Wheels on top of the train

engaged with the guiding rail. The structural support necessary for the

guide rail immediately nullified the economy in land use which was the main

argument in favour of monorails.

The best known such system was designed by Tunis

and built by August Belmont. It was 1,2 miles long (2.4 km) and ran between

Barton Station on the New York, New

Haven & Hartford Railroad and City Island (Marshall's

Corner) in 1,2 minutes. The overhead guide rail was arranged to make the

single car lean over on curve and the line was designed for high speeds.

It ran for four months in l9I0, but on 17 July f that year the driver took

curve too slowly, the guidance system failed and the car crashed with 100

people on board. It never ran again.

The most successful modern monorails have been the

invention of Dr Axel L Wenner-Gren, an industrialist born in Sweden. Alweg

lines use concrete beam carried on concrete supports; the beam can be

high in the air, at ground level or in tunnel, as required. The cars

straddle the beam, supported by rubber-tyred wheels on top f the beam;

there are also horizontal wheels in two rows on each side underneath,

bearing on the sides of the beam near the top and bottom of it. Thus there

are five bearing surfaces, as in the Behr system, but combined to use

single beam instead of massive steel trestle framework. The carrying

wheels m up into the centre line of the cars, suitably enclosed.

Electric current is picked up from power lines at the side

of the beam. number of successful lines have been built on the Alweg

system, including line 8.25 miles (13.3 km) long between Tokyo and its

Haneda airport.

There are several other 'saddle' type systems on the same principle as

the Alweg, including small industrial system used on building sites and

for agricultural purposes which can run without driver. With all these

systems, trains are diverted from one track to another by moving pieces of

track sideways to bring in another piece of track to form new link, or by

using flexible section of track to give the same result.

Other systems

Another monorail system suspends the car beneath an overhead carrying

rail. The wheels must be over the centre line of the car, so the support

connected between

ri1 and car is to one side, or offset. This allows the rail to be

supported from the other side. Such system was built between the towns of

Barmen and Elberfeld in Germany in 1898-1901 and was extended in 1903 to

length of 8.2 miles (13 km). It has run successfully ever since, with

remarkable safety record. Tests in the river valley between the towns

showed that monorail would be more suitable than conventional railway

in the restricted space available because monorail cars could take sharper

curves in comfort.

The rail is suspended on steel structure, mostly over the River Wupper

itself. The switches or points on the line are in the form of switch

tongue forming an inclined plane, which is placed over the rail; the car

wheels rise on this plane and are thus led to the siding.

An experimental line using the same principle of suspension, but with

the r driven by means f an aircraft propeller, was designed by George

Bennie and built at Milngavie (Scotland) in 1930. The line was too short

for high speeds, but it was claimed that 200 mph (322 km/h) was possible.

There was an auxiliary rail below the car on which horizontal wheels ran to

control the sway.

modern system, the SAFEGE developed in France, has

suspended cars but with the 'rail' in the form of steel box section split

on the underside to allow the car supports to pass through it. There are

two rails inside the b, one on each side of the slot, and the cars are

actually suspended from four-wheeled bogies running on the two rails.

Underground railways

The first underground railways were those used in mines, with small

trucks pushed by hand or, later, drawn by ponies, running on first wooden,

then iron, and finally steel rails. Once the steam railway had arrived,

howevr, thoughts soon turned to building passenger railways under the

ground in cities to avoid the traffic congestion which was already making

itself felt in the streets towards the middle of the 19th century.

The first underground passenger railway was opened in London on 1

January, 1863. This was the Metropolitan Railway, 3.75 miles (6 km) long,

which ran from Paddington to Farringdon Street. Its broad gauge (7 ft, 2.13

m) trains, supplied by the Great Western Railway, were soon carrying nearly

27,000 passengers day. Other underground lines followed in London, and in

Budapest, Berlin, Glasgow, Paris and later in the rest of Europe, North and

South America, Russia, Japan, China, Spain, Portugal and Scandinavia, and

lans and studies for yet more underground railways have already been

turned into reality r soon will be all over the world. Quite soon

every major city able to d so will have its underground railway. The

reason is the same as that

which inspired the Metropolitan Railway over 100 years ago traffic

congestion.

The first electric tube railway [subway] in the world,the City and

South London, was opened in 1890 and all subsequent tube railways have been

electrically worked. Subsurface cut-and-cover lines everywhere are also

electrically worked. Th early locomotives used on undergroundrailways have

given way to multiple-unit trains, with separate motors at various points

along the train driving the wheels, but controlled from single driving

b.

Modern underground railway rolling stock usually has

plenty of standing space to cater for peak-hour crowds and alarge number of

doors, usually opened and closed by the driver or guard, so that passengers

can enter and leave the trains quickly at the many, closely spaced

stations. Average underground railway speeds are not high often between

20 and 25 mph (32 to 60km/h) including stops, but the trains are usually

much quicker than surface transport in the same area. Where underground

trains emerge into the open on the dge

of cities, and stations are greater distance apart, they can often attain

well over 60 mph (97 km/h).

The track and ltricit supply are usually much the same as that of

main-line railways and most underground lines use forms f automatic

signalling worked by the trains themselves and similar to that used by

orthodox railway systems. The track curcuit is the basic component of

automatic signalling of this type on ll kinds of railways. Underground

railways rely heavily on automatic signalling because of the close

headways, the short time intervals between trains.

Some railways have n signals in sight, but the signal 'aspects'

green, yellow and red are displayed to the driver in the of his

train. Great advances are being made also with automatic driving, now in

use in number of cities. he Victoria Line system in London, the most

fully automatic line now in operation, uses codes in the rails for both

safety signalling and automatic driving, the codes being picked up by coils

on the train and passed to the driving and monitoring equipment.

Code systems are used on other underground railways but sometimes they

feed information to central computer, which calculates where the train

should be at any given time, nd instructs the train to slow down, speed

up, stop, or take any other action needed.



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