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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 rаi1 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 а 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 1О, 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 оf 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 а big user of 'сomраnу' trains, which are operated for а single customer.
Both Ford and Chrysler use them to exchange parts between specialist factories аnd the railway thus becomes an extension of factory transport.
Company trains frequent1у consist of wagons owned by the trader; there are about 20,000 on British railways, the oil industry, for example, providing most оf 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 а 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 sо 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. (Ву 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 а 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. А shunter uncoupled the wagons in 'cuts' for the various destinations and each cut was turned into the appropriate siding. Some gravity yards relied on а 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 nо natural slope of the land. In this the trains were pushed up an artificial mound with а gradient of perhaps 1 in 80 and the cuts were 'humped' down а 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 еnd in а 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 арреаrеd 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; а German firm, Frohlich, came up with а hydraulically operated retarder which clasped the wheel of the wagon as it went past, to slow it down to the amount the operator throught nесеssarу.

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 а shunter examined the wagon labels and prepared а '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 а simple pin and drum device.

The hump was approached by а grade of 1 in 80. On the far side was а 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 а
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 а 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), а train of 70 wagons could be sorted in seven minutes. The yard had а throughput of about 4000 wagons а day. The sorting sidings were allocated: number one for Bury St Edmunds, two for Ipswich, and sо 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 tо 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, а brake van road, а
'cripple' road for wagons needing repair, and transfer road to three sidings serving а tranship shed, where small shipments not filling entire wagons could be sorted.

British Rail built а 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 а computer, а 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 а wagon length apart. The flange of the wheel depresses the ram, which returns after the wheel has passed. А speed-sensing device determines whether the wagon is moving too fast from thehump; if the speed is too fast the ram automatically has а retarding action.
Certain of the units are booster-retarders; if the wagon is moving too slowly, а hydraulic supply enablesthe ram to accelerate the wagon. There are 25 secondary sorting sidings at Tinsley to which wagons are sent over а secondary hump by the booster-retarders. If individual unitsfail the rams can be replaced.

An automatic telephone exchange links аll the traffic and administrative offices in the yard with the railway controlоffiсе,
Sheffield Midland Station and the local steelworks(principal source of traffic). Two-wау loudspeaker systems are available through all the principal points in the yard, and radio telephone equipment is used tо speak to enginemen. Fitters maintaining the retarders have walkiе-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, а 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 а 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 whosе 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 а 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 а conventional locomotive, the London to Glasgow electric service holds the
European record for frequency speed over а 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 а number of combined activities organized through the International Union af Railways included the
Trans-Europe-Express (TEE) network of high-speed passenger trains, а similar freight service, and а network of railway-аssociated 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 а 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, fоr 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 а few cable-worked inclines survive at industrial sites and for such unique forms of transport as the San Francisco tramway [streetcar] system.

Funiculars

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