Underwater

Underwater is a term describing the realm below the surface of water where the water exists in a natural feature (called a body of water) such as an ocean, sea, lake, pond, or river. Three quarters of the planet Earth are covered by water. A majority of the planet's solid surface is abyssal plain, at depths between 4,000 and 5,500 metres (13,000 and 18,000 ft) below the surface of the oceans. The solid surface location on the planet closest to the center of the orb is the Challenger Deep, located in the Mariana Trench at a depth of 10,924 m (35,838 ft) under the sea.
Although a number of human activities are conducted underwater—such as research, scuba diving for work or recreation, or even underwater warfare with submarines, this very extensive environment on planet Earth is hostile to humans in many ways and therefore little explored. But it can be explored by sonar, or more directly via manned or autonomous submersibles. The ocean floors have been surveyed via sonar to at least a coarse resolution; particularly-strategic areas have been mapped in detail, in the name of detecting enemy submarines, or aiding friendly ones, though the resulting maps may still be classified.

An immediate obstacle to human activity under water is the fact that human lungs cannot naturally function in this environment. Unlike the gills of fish, human lungs are adapted to the exchange of gases at atmospheric pressure, not liquids. Aside from simply having insufficient musculature to rapidly move water in and out of the lungs, a more significant problem for all air-breathing animals, such as mammals and birds, is that water contains so little dissolved oxygen compared with atmospheric air. Air is around 21% O₂; water typically is less than 0.001% dissolved oxygen.
The density of water also causes problems that increase dramatically with depth. The atmospheric pressure at the surface is 14.7 pounds per square inch or around 100 kPa. A comparable water pressure occurs at a depth of only 10 m (33 ft) (9.8 m (32 ft) for sea water). Thus, at about 10 m below the surface, the water exerts twice the pressure (2 atmospheres or 200 kPa) on the body as air at surface level.

For solid objects like human bones and muscles, this added pressure is not much of a problem; but it is a problem for any air-filled spaces like the mouth, ears, paranasal sinuses and lungs. This is because the air in those spaces reduces in volume when under pressure and so does not provide those spaces with support from the higher outside pressure. Even at a depth of 8 ft (2.4 m) underwater, an inability to equalize air pressure in the middle ear with outside water pressure can cause pain, and the tympanic membrane can rupture at depths under 10 ft (3 m). The danger of pressure damage is greatest in shallow water because the rate of pressure change is greatest at the surface of the water. For example the pressure increase between the surface and 10 m (33 ft) is 100% (100 kPa to 200 kPa), but the pressure increase from 30 m (100 ft) to 40 m (130 ft) is only 25% (400 kPa to 500 kPa).
Any object immersed in water is provided with a buoyant force that counters the force of gravity, appearing to make the object less heavy. If the overall density of the object exceeds the density of water, the object sinks. If the overall density is less than the density of water, the object rises until it floats on the surface.

 

With increasing depth underwater, sunlight is absorbed, and the amount of visible light diminishes. Because absorption is greater for long wavelengths (red end of the visible spectrum) than for short wavelengths (blue end of the visible spectrum), the colour spectrum is rapidly altered with increasing depth. White objects at the surface appear bluish underwater, and red objects appear dark, even black. Although light penetration will be less if water is turbid, in the very clear water of the open ocean less than 25% of the surface light reaches a depth of 10 m (33 feet). At 100 m (330 ft) the light present from the sun is normally about 0.5% of that at the surface.

The euphotic depth is the depth at which light intensity falls to 1% of the value at the surface. This depth is dependent upon water clarity, being only a few meters underwater in a turbid estuary, but may reach up to 200 meters in the open ocean. At the euphotic depth, plants (such as phytoplankton) have no net energy gain from photosynthesis and thus cannot grow.

At depths greater than a few hundred meters, the sun has little effect on water temperature, because the sun's energy has been absorbed by water at the surface. In the great depths of the ocean the water temperature is very cold. In fact, 75% of the water in the world ocean (the great depths) has a temperature between 0 °C and 2 °C.

Water conducts heat around twenty five times more efficiently than air. Hypothermia, a potentially fatal condition, occurs when the human body's core temperature falls below 35 °C. Insulating the body's warmth from water is the main purpose of diving suits and exposure suits when used in water temperatures below 25 °C.

Sound is transmitted about 4.3 times faster in water (1,484 m/s in fresh water) as it is in air (343 m/s). The human brain can determine the direction of sound in air by detecting small differences in the time it takes for sound waves in air to reach each of the two ears. For these reasons divers find it difficult to determine the direction of sound underwater. However, some animals have adapted to this difference and many use sound to navigate underwater.

Indian Railways

Indian Railways (reporting mark IR) is an Indian state-owned railway company headquartered in New Delhi, India. It is owned and operated by the Government of India through the Ministry of Railways. Indian Railways has 114,500 kilometres (71,147 mi). of total track over a route of 65,000 kilometres (40,389 mi) and 7,500 stations. It has the world's fourth largest railway network after those of the United States, Russia and China. The railways carry over 30 million passengers and 2.8 million tons of freight daily.In 2011-2012 Railway earnt Rs 104278.79 crores which consists of Rs 69675.97 crores from freight and 28645.52 crores from passengers tickets.
Indian Railways is the world's fourth largest commercial or utility employer, by number of employees, with over 1.4 million employees. after Wal-Mart with 2.1 million employees, China National Petroleum Corporation with 1.61 million employees and State Grid Corporation of China with 1.53 million employees. As for rolling stock, IR owns over 240,000 (freight) wagons, 60,000 coaches and 9,000 locomotives.
Railways were first introduced to India in 1853. By 1947, the year of India's independence, there were forty-two rail systems. In 1951 the systems (many of which were already government-owned) were nationalized as one unit, the Indian Railways, becoming one of the largest networks in the world. IR operates both long distance and suburban rail systems on a multi-gauge network of broad, metre and narrow gauges. It also owns locomotive and coach production facilities. The Indian railways is proposing to build the highest railway track in the world overtaking the current record of the Beijing-Lhasa Railway line.

History

Main article: History of rail transport in India

India's first train run between Mumbai and Thane

The B.B. & C.I. Railway Head Offices, 1905

The history of rail transport in India began in the mid-nineteenth century. In 1849, there was not a single kilometer of railway line in India. A British engineer, Robert Maitland Brereton, was responsible for the expansion of the railways from 1857 onwards. The Allahabad-Jubbulpore branch line of the East Indian Railway had been opened in June 1867. Brereton was responsible for linking this with the Great Indian Peninsula Railway, resulting in a combined network of 6,400 km (4,000 mi). Hence it became possible to travel directly from Bombay to Calcutta. This route was officially opened on 7th March 1870 and it was part of the inspiration for French writer Jules Verne's book Around the World in Eighty Days. At the opening ceremony, the Viceroy Lord Mayo concluded that “it was thought desirable that, if possible, at the earliest possible moment, the whole country should be covered with a network of lines in a uniform system”.
By 1875, about £95 million were invested by British companies in Indian guaranteed railways. By 1880 the network had a route mileage of about 14,500 km (9,000 mi), mostly radiating inward from the three major port cities of Bombay, Madras and Calcutta. By 1895, India had started building its own locomotives, and in 1896 sent engineers and locomotives to help build the Uganda Railways.
In 1900, the GIPR became a government owned company. The network spread to the modern day states of Assam, Rajasthan and Andhra Pradesh and soon various independent kingdoms began to have their own rail systems. In 1901, an early Railway Board was constituted, but the powers were formally invested under Lord Curzon. It served under the Department of Commerce and Industry and had a government railway official serving as chairman, and a railway manager from England and an agent of one of the company railways as the other two members. For the first time in its history, the Railways began to make a profit.
In 1907 almost all the rail companies were taken over by the government. The following year, the first electric locomotive made its appearance. With the arrival of World War I, the railways were used to meet the needs of the British outside India. With the end of the war, the railways were in a state of disrepair and collapse.
In 1920, with the network having expanded to 61,220 km, a need for central management was mooted by Sir William Acworth. Based on the East India Railway Committee chaired by Acworth, the government took over the management of the Railways and detached the finances of the Railways from other governmental revenues.
The period between 1920 to 1929 was a period of economic boom, there were 41,000 miles of railway line serving every district in the country. At that point of time, the railways represented a capital value of some 687 millions sterling, and they carried over 620 millions of passengers and approximately 90 million tons of goods each year. Following the Great Depression, the company suffered economically for the next eight years. The Second World War severely crippled the railways. Trains were diverted to the Middle East and the railways workshops were converted to ammunitions workshops. By 1946 all rail systems had been taken over by the government.

Organizational structure

Main article: Indian Railway organisational structure

Railway zones

Indian Railways headquarters in Delhi

CR's headquarters Chhatrapati Shivaji Terminus

NR's headquarters New Delhi Railway Station

Southern Railway headquarters, Chennai

Western Railway HQ, Mumbai

Indian Railways is divided into several zones, which are further sub-divided into divisions. The number of zones in Indian Railways increased from six to eight in 1951, nine in 1952 to sixteen in 2003 then to seventeen in 2010. Each zonal railway is made up of a certain number of divisions, each having a divisional headquarters. There are a total of sixty-eight divisions.
Each of the seventeen zones is headed by a General Manager (GM) who reports directly to the Railway Board. The zones are further divided into divisions under the control of Divisional Railway Managers (DRM). The divisional officers of engineering, mechanical, electrical, signal and telecommunication, accounts, personnel, operating, commercial and safety branches report to the respective Divisional Manager and are in charge of operation and maintenance of assets. Further down the hierarchy tree are the Station Masters who control individual stations and the train movement through the track territory under their stations' administration.

Sl. No	Name	Abbr.	Date Established	Route KMs	Headquarters	Divisions
1.	Central	CR	1951-11-05	3905	Mumbai	Mumbai, Bhusawal, Pune, Solapur, Nagpur
2.	East Central	ECR	2002-10-01	3628	Hajipur	Danapur, Dhanbad, Mughalsarai, Samastipur, Sonpur
3.	East Coast	ECoR	2003-04-01	2572	Bhubaneswar	Khurda Road, Sambalpur, Visakhapatnam
4.	Eastern	ER	1952-04	2414	Kolkata	Howrah, Sealdah, Asansol, Malda
5.	North Central	NCR	2003-04-01	3151	Allahabad	Allahabad, Agra, Jhansi
6.	North Eastern	NER	1952	3667	Gorakhpur	Izzatnagar, Lucknow, Varanasi
7.	North Western	NWR	2002-10-01	5459	Jaipur	Jaipur, Ajmer, Bikaner, Jodhpur
8.	Northeast Frontier	NFR	1958-01-15	3907	Guwahati	Alipurduar, Katihar, Rangia, Lumding, Tinsukia
9.	Northern	NR	1952-04-14	6968	Delhi	Delhi, Ambala, Firozpur, Lucknow, Moradabad
10.	South Central	SCR	1966-10-02	5803	Secunderabad	Secunderabad, Hyderabad, Guntakal, Guntur, Nanded, Vijayawada
11.	South East Central	SECR	2003-04-01	2447	Bilaspur	Bilaspur, Raipur, Nagpur
12.	South Eastern	SER	1955	2631	Kolkata	Adra, Chakradharpur, Kharagpur, Ranchi
13.	South Western	SWR	2003-04-01	3177	Hubli	Hubli, Bangalore, Mysore
14.	Southern	SR	1951-04-14	5098	Chennai	Chennai, Trichy, Madurai, Palakkad, Salem, Trivandrum (Thiruvananthapuram)
15.	West Central	WCR	2003-04-01	2965	Jabalpur	Jabalpur, Bhopal, Kota
16.	Western	WR	1951-11-05	6182	Mumbai	Mumbai Central, Ratlam, Ahmedabad, Rajkot, Bhavnagar, Vadodara

Recruitment and training

Main article: Centralised Training Institutes of the Indian Railways

Staff are classified into gazetted (Group 'A' and 'B') and non-gazetted (Group 'C' and 'D') employees.^[16] The recruitment of Group 'A' gazetted employees is carried out by the Union Public Service Commission through exams conducted by it.^[17] The recruitment to Group 'C' and 'D' employees on the Indian Railways is done through 19 Railway Recruitment Boards which are controlled by the Railway Recruitment Control Board (RRCB).^[18] The training of all cadres is entrusted and shared between six centralized training institutes. These are following list of Group A services which are recruited by the UPSC(Union Public Service Commission ) of India
UPSC Civil Services Exam
1) Indian Railway Traffic Service, Group ‘A’.
2) Indian Railway Accounts Service, Group 'A'.
3) Indian Railway Personnel Service, Group ‘A’.
4) Railway Protection Force, Group ‘A’
UPSC Engineering Services Exam
1) Indian Railway Service of Engineers, Group ‘A’
2) Indian Railway Stores Service, Group ‘A’
3) Indian Railway Service of Mechanical Engineers, Group ‘A’
4) Indian Railway Service of Electrical Engineers, Group ‘A’
5) Indian Railway Service of Signal Engineers, Group ‘A’
UPSC Special Class Railway Apprentice Examination for recruitment to the Indian Railway Service of Mechanical Engineers

Production units

A modern pantograph. The device shown is technically a half-pantograph.

CLW made WAP-5 30022(CLW made WAP-5 locos don't have fluted body shell) rests at Bhopal

WDP4 Diesel Locomotive Baaz which is now at New Jalpaiguri

Indian Railways manufactures much of its rolling stock and heavy engineering components at its six manufacturing plants, called Production Units, which are managed directly by the Ministry. Popular rolling stock builders such as CLW and DLW for electric and diesel locomotives; ICF and RCF for passenger coaches are Production Units of Indian Railways. Over the years, Indian Railways has not only achieved self-sufficiency in production of rolling stock in the country but also exported rolling stock to other countries. Each of these six production units is headed by a General Manager, who also reports directly to the Railway Board. The six Production Units are:-

Sl. No	Name	Abbr.	Year Established	Location	Main products
1.	Golden Rock Locomotive Workshops	GOC	1928	Trichy	Diesel-electric Locomotives
2.	Chittaranjan Locomotive Works	CLW	1947	Chittaranjan , Asansol	Electric Locomotives
3.	Diesel Locomotive Works	DLW	1961	Varanasi	Diesel Locomotives
4.	Diesel-Loco Modernisation Works	DMW	1981	Patiala	Diesel-electric Locomotives
5.	Integral Coach Factory	ICF	1952	Chennai	Passenger coaches
6.	Rail Coach Factory	RCF	1986	Kapurthala	Passenger coaches
7.	Rail Wheel Factory	RWF	1984	Bangalore	Railway wheels and axles
8.	Rail Wheel Factory	RWF	2011	Chhapra	Railway wheels and axles

Other subsidiaries

There also exist independent organizations under the control of the Railway Board for electrification, modernization, research and design and training of officers, each of which is headed by an officer of the rank of General Manager. A number of Public Sector Undertakings, which perform railway-related functions ranging from consultancy to ticketing, are also under the administrative control of the Ministry of railways.
There are eleven public undertakings under the administrative control of the Ministry of Railways,^[19] viz.

• Rail India Technical and Economic Services Limited (RITES);
• Indian Railway Construction (IRCON) International Limited;
• Indian Railway Finance Corporation Limited (IRFC);
• Container Corporation of India Limited (CONCOR);
• Konkan Railway Corporation Limited (KRCL).
• Indian Railway Catering and Tourism Corporation Limited (IRCTC);
• Railtel Corporation of India Limited (Rail Tel);
• Mumbai Rail Vikas Nigam Limited (MRVNL);
• Rail Vikas Nigam Limited (RVNL); and
• Dedicated Freight Corridor Corporation of India Limited (DFCCIL); and
• Bharat Wagon and Engineering Co. Ltd. (BWEL).

The Centre for Railway Information Systems (CRIS) was set up as a registered society to design and implement various railway computerization projects.

Locomotives

Main article: Locomotives in India

Two steam engines at water refilling station at Agra station

Locomotives in India consist of electric and diesel locomotives. Steam locomotives are no longer used, except in heritage trains. Locomotives are also called locos or engines. In India, locomotives are classified according to their track gauge, motive power, the work they are suited for and their power or model number. The class name includes this information about the locomotive. It comprises 4 or 5 letters. The first letter denotes the track gauge. The second letter denotes their motive power (Diesel or Electric) and the third letter denotes the kind of traffic for which they are suited (goods, passenger, mixed or shunting). The fourth letter used to denote locomotives' chronological model number. However, from 2002 a new classification scheme has been adopted. Under this system, for newer diesel locomotives, the fourth letter will denote their horsepower range. Electric locomotives don't come under this scheme and even all diesel locos are not covered. For them this letter denotes their model number as usual.
A locomotive may sometimes have a fifth letter in its name which generally denotes a technical variant or subclass or subtype. This fifth letter indicates some smaller variation in the basic model or series, perhaps different motors, or a different manufacturer. With the new scheme for classifying diesel locomotives (as mentioned above) the fifth item is a letter that further refines the horsepower indication in 100 hp increments: 'A' for 100 hp, 'B' for 200 hp, 'C' for 300 hp, etc. So in this scheme, a WDM-3A refers to a 3100 hp loco, while a WDM-3F would be a 3600 hp loco.

Note: This classification system does not apply to steam locomotives in India as they have become non-functional now. They retained their original class names such as M class or WP class.

Technical details

Track and gauge

Indian railways uses four gauges, the 1,676 mm (5 ft 6 in) broad gauge which is wider than the 1,435 mm (4 ft 8 ¹⁄₂ in) standard gauge; the 1,000 mm (3 ft 3 ³⁄₈ in) metre gauge; and two narrow gauges, 762 mm (2 ft 6 in) and 610 mm (2 ft) . Track sections are rated for speeds ranging from 75 to 160 km/h (47 to 99 mph).
The total length of track used by Indian Railways was about 114,000 km (71,000 mi) while the total route length of the network was 64,215 km (39,901 mi) on 31 March 2011.^[20] About 33% of the route-kilometer and 44% of the total track kilometer was electrified on 31 March 2011.^[20]

Broad gauge is the predominant gauge used by Indian Railways.

Broad gauge is the predominant gauge used by Indian Railways. Indian broad gauge—1,676 mm (5 ft 6 in)—is the most widely used gauge in India with 102,000 km (63,000 mi) of track length (90% of entire track length of all the gauges) and 54,600 km of route-kilometer (85% of entire route-kilometer of all the gauges) on 31 March 2011.
In some regions with less traffic, the meter gauge (1,000 mm/3 ft 3 ³⁄₈ in) is common, although the Unigauge project is in progress to convert all tracks to broad gauge. The metre gauge had about 9,000 km (5,600 mi) of track length (7.9% of entire track length of all the gauges) and 7,500 km of route-kilometer (11.6% of entire route-kilometer of all the gauges) on 31 March 2011.
The Narrow gauges are present on a few routes, lying in hilly terrains and in some erstwhile private railways (on cost considerations), which are usually difficult to convert to broad gauge. Narrow gauges had a total of 2,400 route-kilometre on 31 March 2011. The Kalka-Shimla Railway, the Kangra Valley Railway and the Darjeeling Himalayan Railway are three notable hill lines that use narrow gauge, but the Nilgiri Mountain Railway is a metre gauge track.^[21] These four rail lines will not be converted under the Unigauge project.

The Indian Railways serves every major populated region in the country

The share of broad gauge in the total route-kilometer has been steadily rising, increasing from 47% (25,258 route-km) in 1951 to 85% in 2011 whereas the share of meter gauge has declined from 45% (24,185 route-km) to less than 12% in the same period and the share of narrow gauges has decreased from 8% to 3%. However, the total route-kilometer has increased by only 18% (by just 10,000 km from 53,596 route-km in 1951) in the last sixty years. This compares very poorly with Chinese railways, which increased from about 27,000 route-km at the end of second world war to about 100,000 route-km in 2011, an increase of more than threefold. More than 28,000 route-km (34% of the total route-km) of Chinese railway is electrified compared to only about 21,000 route-km of Indian railways.
Double-decker AC trains have been introduced in India. The first double decker train was Flying Rani introduced in 2005 while the first double-decker AC train in the Indian Railways was introduced in November 2010, running between the Dhanbad and Howrah stations having 10 coaches and 2 power cars.^[22]
Sleepers (ties) are made up of prestressed concrete, or steel or cast iron posts, though teak sleepers are still in use on a few older lines. The prestressed concrete sleeper is in wide use today. Metal sleepers were extensively used before the advent of concrete sleepers. Indian Railways divides the country into four zones on the basis of the range of track temperature. The greatest temperature variations occur in Rajasthan.

Electrification

As of 31 March 2011, 21,014 km of the total 64,215 km route length is electrified (33%).^[23] Since 1960, almost all electrified sections on IR use 25,000 V AC traction through overhead catenary delivery. A major exception is the entire Mumbai section, which uses 1,500 V DC,^[25] but is currently undergoing change to the 25,000 V AC system. Another exception is the Kolkata Metro, which uses 750 V DC delivered through a third rail.
Traction voltages are changed at two places close to Mumbai. Central Railway trains passing through Kasara and Karjat switch from AC to DC using a neutral section near Kalyan. Western Railway trains switch power on the fly, in a section near Dahisar, where the train continues with its own momentum for about 30 m through a non-electrified section of catenary called a dead zone.^[25] All electric engines and EMUs operating in this section are the necessary AC/DC dual system type (classified "WCAM" by IndianRailways).

Railway links to adjacent countries

See also: Rail transport in India#International links

Existing rail links:

• Nepal – Break-of-gauge – Gauge conversion under uni-gauge project
• Pakistan – same Broad Gauge. Thar Express to Karachi and the more famous Samjhauta Express international train from Lahore, Pakistan to Amritsar (Attari).
• Bangladesh – Same Broad Gauge. The Maitri Express between Dhaka and Kolkata started in April 2008 using the Gede-Darsana route, in addition to a Freight Train service from Singhabad and Petrapole in India to Rohanpur and Benapole in Bangladesh A second passenger link between Agartala, India and Akhaura Upazila, Bangladesh was approved by the Government of India in September 2011.^[26]

Under construction / Proposed links:

• Bhutan – railways under construction – Same gauge
• Myanmar – Manipur to Myanmar (under construction)
• China – Indian Railways and rail authorities in People's Republic of China are interested in starting a high-speed rail link that would link New Delhi with Kunming, China via Myanmar.The rail link would utilize the under construction railway from Manipur, India to Myanmar and the under construction railway from Kunming to Myanmar.
• Vietnam – On 9 April 2010, Former Union Minister of India, Shashi Tharoor announced that the central government is considering a rail link from Manipur to Vietnam via Myanmar.
• Thailand - possible if Burma Railway is rebuilt.^[29] Would also allow trains to Malaysia and Singapore.

Types of passenger services

Delhi Duronto Express, as it rolls out of Sealdah with a Ghaziabad WAP 7 in Duronto livery

Seen here is the coaches of the Shatabdi Express, a medium-distance high-speed train connecting the four metros with the important destinations in the region.

Seen here is the Rajdhani Express, which is a long-distance high-speed train connecting major state capitals with New Delhi.

Trains are classified by their average speed.^[30] A faster train has fewer stops ("halts") than a slower one and usually caters to long-distance travel.

Rank	Train	Description
1	Duronto Express	These are the non-stop point to point rail services (except for operational stops) introduced for the first time in 2009 . These trains connect the metros and major state capitals of India and are faster than Rajdhani Express.These trains are now of the Highest Priority to the Indian Railways. The Duronto services consists of classes of accommodation namely first AC, two-tier AC, three-tier AC, AC 3 Tier Economy, Sleeper Class, General Class.
2	Rajdhani Express	These are all air-conditioned trains linking major cities to New Delhi. The Rajdhanis have high priority and are one of the fastest trains in India, travelling at about 130 km/h (82 mph). There are only a few stops on a Rajdhani route.
3	Shatabdi Express	The Shatabdi trains are AC intercity seater-type trains for travel during day.
4	Garib Rath	Fully air conditioned trains, designed for those who cannot afford to travel in the expensive Shatabti and Rajdhani Express. Garib Rath means "Chariot of the Poor". The maximum speed is 130 km/h.
5	Jan Shatabdi	Jan Shatabdi Express are a more affordable variety of the Shatabdi Express, which has both AC and non-AC classes. The maximum speed is 130 km/h.
6	Sampark Kranti Express	Sampark Kranti Express trains are a series of trains that provide quick connectivity from a particular state to the national capital, New Delhi.
7	Superfast Express/Mail	These are trains that have an average speed greater than 55 km/h (34 mph). Tickets for these trains have an additional super-fast surcharge.
8	Express	These are the most common kind of trains in India. They have more stops than their super-fast counterparts, but they stop only at relatively important intermediate stations.
9	Passenger and Fast Passenger	These are slow trains that stop at most stations along the route and are the cheapest trains. The trains generally have unreserved seating accommodation but some night trains have sleeper, First Class and 3A compartments.
10	Suburban trains	These trains operate in urban areas, usually stop at all stations and have unreserved seating accommodation.
11	Metros and Monorails	These trains are designed for city transport in metro cities of India.

Accommodation classes

Interior of a First Class(1A) compartment in the Rajdhani Express.

Air-conditioned Chair Car(CC) coaches in an Shatabdi Express.

Interior of an air-conditioned Chair Car coach(CC) in an Jan Shatabdi Express.

A typical sleeper class coach

Several long trains are composed of two to three classes of travel, such as a 1st and 2nd classes which have different pricing systems for various amenities. The 1st Class refers to coaches with separate cabins, coaches can be air-conditioned or non air-conditioned.
Further, other AC classes can have 2 or 3 tier berths, with higher prices for the former, 3-tier non-AC coaches or 2nd class seating coaches, which are popular among passengers going on shorter journeys.
In air-conditioned sleeper classes passengers are provided with sheets, pillows and blankets. Meals and refreshments are provided, to all the passengers of reserved classes, either through the on-board pantry service or through special catering arrangements in trains without pantry car. Unreserved coach passengers have options of purchasing from licensed vendors either on board or on the platform of intermediate stops.
The amenities depend on the popularity and length of the route. Lavatories are communal and feature both the Indian style as well as the Western style.
The following table lists the classes in operation. Not all classes may be attached to a rake though.

Class[31]	Description[31][32]
1A	The First class AC: This is the most expensive class, where the fares are on par with airlines. There are eight cabins (including two coupes) in the full AC First Class coach and three cabins (including one coupe) in the half AC First Class coach. The coach has an attendant, to help the passengers. Bedding is included with the fare in IR. This air conditioned coach is present only on popular routes between metropolitan cities and can carry 18 passengers (full coach) or 10 passengers (half coach). The sleeper berths are extremely wide and spacious. The coaches are carpeted, have sleeping accommodation and have privacy features like personal coupes. Passengers are served exclusive pantry cooked food (included in the fare in Rajdhani Express trains only). This class is available on broad gauge and metre gauge trains.
2A	AC-Two tier: Madarchod These air-conditioned coaches have sleeping berths across eight partitions (with curtains). Each partition has either four or two berths. Berths are usually arranged in two tiers in bays of six, four across the width of the coach then the gangway then two berths longways, with curtains provided to give some privacy from those walking up and down. Bedding is included with the fare. Passengers are served food. A broad gauge coach can carry 48 passengers (full coach) or 20 passengers (half coach). This class is available on broad gauge and metre gauge trains.
FC	First class: Same as 1AC, without the air conditioning. No bedding is available in this class. The berths are wide and spacious. There is a coach attendant to help the passengers. This class is not very common. This class is available on all gauges.
3A	AC three tier: Air conditioned coaches with 64 sleeping berths. Berths are usually arranged as in 2AC but with three tiers across the width and two longways as before giving eight bays of eight. They are slightly less well-appointed, usually no reading lights or curtained off gangways. Bedding is included with fare. It carries 64 passengers in broad gauge. This class is available only on broad gauge.
3E	AC three tier (Economy): Air conditioned coaches with sleeping berths, present in Garib Rath Trains. Berths are usually arranged as in 3AC but with three tiers across the width and three longways. They are slightly less well-appointed, usually no reading lights or curtained off gangways. Bedding is not included with fare.
CC	AC chair car: An air-conditioned seater coach with a total of five seats in a row used for day travel between cities.
EC	Executive class chair car: An air-conditioned coach with large spacious seats and legroom. It has a total of four seats in a row used for day travel between cities. This class of travel is only available on Shatabdi Express trains.
SL	Sleeper class: The sleeper class is the most common coach on IR, and usually ten or more coaches could be attached. These are regular sleeping coaches with three berths vertically stacked. In broad gauge, it carries 72 passengers per coach. Railways have modified certain Sleeper Coaches on popular trains to accommodate 81 passengers in place of regular 72 passengers. This has met with criticism from the travellers and are now being reverted to 72 sleepers.
2S	Seater class: same as AC Chair car, but with bench style seats and without the air-conditioning.
UR	Unreserved: The cheapest accommodation, the seats usually made up of pressed wood, but the cushioned seats have been rapidly replaced. Although entry into the compartment is guaranteed, a sitting seat is not guaranteed. Tickets are issued in advace for a minimum journey of more than 24 hours. Tickets issued are valid on any train on the same route if boarded within 24 hours of buying the ticket. These coaches are usually very crowded.

At the rear of the train is a special compartment known as the guard's cabin. It is fitted with a transceiver and is where the guard usually gives the all clear signal before the train departs. A standard passenger rake generally has four general compartments, two at the front and two behind, of which one is exclusively for ladies. The exact number varies according to the demand and the route. A luggage compartment can also exist at the front or the back. In some trains a separate mail compartment is present. In long-distance trains a pantry car is usually included in the centre.

Train numbering

Effective 20 December 2010, the railways will deploy a 5 digit numbering system instead of the 4 digit system. The need is due to the fact that the Indian Railways runs 10,000 trains daily.^[33] Only a prefix of the digit 1 will be added to the four-digit numbers of the existing trains to make the transition smoother. The special trains run to clear festivals and holiday rush shall have the prefix of 0 (zero)

Notable trains and achievements

A Beyer Garratt 6594 Engine seen at the National Rail Museum

A tight loop (Agony Point) on the Darjeeling Himalayan Railway in West Bengal.

A view of the Pamban Railway Bridge, which links Rameshwaram to the mainland.Thousands of pilgrims cross the sea every day to visit the island.

There are two UNESCO World Heritage Sites on IR – the Chatrapati Shivaji Terminus^[34] and the Mountain Railways of India. The latter is not contiguous, but actually consists of three separate railway lines located in different parts of India:^[35]

• The Darjeeling Himalayan Railway, a narrow gauge railway in West Bengal.
• The Nilgiri Mountain Railway, a metre gauge railway in the Nilgiri Hills in Tamil Nadu
• The Kalka-Shimla Railway, a narrow gauge railway in the Shivalik mountains in Himachal Pradesh. In 2003 the railway was featured in the Guinness Book of World Records for offering the steepest rise in altitude in the space of 96 kilometre.^[36]
• The Maharaja Railways (Gwalior Light Railway), a narrow gauge line of just 0.6m width from Gwalior to Sheopur of 198 km. in length is world's longest narrow gauge railway line is in the UNESCO world heritage tentative list.
• The Neral-Matheran Railway, a narrow gauge railway connecting Matheran is also a historic line.
• The Palace on Wheels is a specially designed train, frequently hauled by a steam locomotive, for promoting tourism in Rajasthan. On the same lines, the Maharashtra government introduced the Deccan Odyssey covering various tourist destinations in Maharashtra and Goa, and was followed by the Government of Karnataka which introduced the Golden Chariot train connecting popular tourist destinations in Karnataka and Goa. However, neither of them has been able to enjoy the popular success of the Palace on Wheels.

• The Samjhauta Express is a train that runs between India and Pakistan. However, hostilities between the two nations in 2001 saw the line being closed. It was reopened when the hostilities subsided in 2004. Another train connecting Khokhrapar (Pakistan) and Munabao (India) is the Thar Express that restarted operations on 18 February 2006; it was earlier closed down after the 1965 Indo-Pak war.

• The Lifeline Express is a special train popularly known as the "Hospital-on-Wheels" which provides healthcare to the rural areas. This train has a carriage that serves as an operating room, a second one which serves as a storeroom and an additional two that serve as a patient ward. The train travels around the country, staying at a location for about two months before moving elsewhere.

• Among the famous locomotives, the Fairy Queen is the oldest operating locomotive in the world today, though it is operated only for specials between Delhi and Alwar. John Bull, a locomotive older than Fairy Queen, operated in 1981 commemorating its 150th anniversary. Kharagpur railway station also has the distinction of being the world's longest railway platform at 1,072 m (3,517 ft). The Ghum station along the Darjeeling Toy Train route is the second highest railway station in the world to be reached by a steam locomotive.^[37] The Mumbai–Pune Deccan Queen has the oldest running dining car in IR.

• The Vivek Express, between Dibrugarh and Kanyakumari, has the longest run in terms of distance and time on Indian Railways network. It covers 4,286 km (2,663 mi) in about 82 hours and 30 minutes.

• The Himsagar Express, between Kanyakumari and Jammu Tawi, has the second longest run in terms of distance and time on Indian Railways network. It covers 3,715 km (2,308 mi) in about 69 hours and 30 minutes. The Bhopal Shatabdi Express is the fastest train in India today having a maximum speed of 150 km/h (93 mph) on the Faridabad–Agra section. The fastest speed attained by any train is 184 km/h (114 mph) in 2000 during test runs.

• The third longest train in terms of distance on Indian Railways network is navyug express between jammu tawi to mangalore covering a distance of 3609 k.m
• Trivandrum Rajdhani is the longest non stop train in on Indian Railways network covering 528 km

History of Earth

How the Earth Was Made

                                  

How the Earth Was Made is an American documentary television series produced by Pioneer Productions for the History channel. It began as a two-hour special exploring the geological history of Earth, airing on December 16, 2007. Focusing on different geologic features of the Earth, the series premiered on February 10, 2009, and the 13-episode first season concluded on May 5, 2009. The second season premiered on November 24, 2009, and concluded on March 2, 2010.

Contents 1 Overview 2 Reception 3 International Broadcast 4 Episodes 4.1 Pilot 4.2 Season 1 (2009) 4.3 Season 2 (2009–10)

Overview

 

How the Earth Was Made premiered as a 90-minute documentary special, narrated by Edward Herrmann, that aired on The History Channel on December 16, 2007, and focused on the geological history of Earth. The History Channel released the original documentary film to Region 1 DVD through Warner Home Video on April 15, 2008 and to Blu-ray through A&E Home Video on May 26, 2009.
The television series premiered on February 10, 2009. Each 45-minute episode focuses on different geologic features and processes of the Earth. The first season, spanning 13 episodes, concluded on May 5, 2009. The second season premiered on November 24, 2009. The first season of the television series was released as a four-volume Region 1 DVD box set on August 25, 2009. The second season was scheduled to be released on June 29, 2010. The Region 4, four-volume DVD set of season one was released by ABC DVD on August 1, 2010 and season two was released on November 1, 2010.

Reception

The editor of the special, Huw Jenkins (although credited as Huw Jenkin), was awarded a 2008 News and Documentary Emmy Award for Outstanding Individual Achievement in a Craft: Editing, in a three way tie.
In its first season, the television series averaged 1.4 million viewers.

International Broadcast

In Australia, the pilot along with both seasons were all broadcast on Pay television through History. For free-to-air viewers, season one also aired on ABC1 each Thursday at 11am from July 22, 2010.

 

 

 

 

Episodes

Season		Episodes	Premiere date	Finale date	DVD release date	Blu-ray release date
	Pilot	1	December 16, 2007		April 20, 2008	May 26, 2009
	1	13	February 10, 2009	May 5, 2009	August 25, 2009	October 26, 2010
	2	13	November 24, 2009	March 2, 2010	June 29, 2010	February 22, 2011

Pilot

Episode #	Title	Original airdate
Pilot	"How the Earth Was Made"	December 16, 2007
This 90-minute documentary explains the geological and biological history of Earth, from its formation 4.5 billion years ago to the present day. Explained are the very beginnings of the Earth; the formation of the crust and atmosphere; the origins of water; when life began in the oceans and moved to the land; the Carboniferous period and how it ended; when dinosaurs ruled the land and the arrival of mammals; and the numerous ice ages. The documentary also explains plate tectonics and ends with the foreseeable next stages of our planet until its final stagnation about 2 billion years in the future.

Season 1 (2009)

Series #	Season #	Title	Original airdate
1	1	"San Andreas Fault"	February 10, 2009
A look at how geologists are keeping an eye on California's 800 mile-long San Andreas Fault which many believe is overdue for a major earthquake in the region that could destroy some of the most valuable real-estate in the world.
2	2	"The Deepest Place on Earth"	February 17, 2009
A look at Challenger Deep, the deepest part of the Mariana Trench, where only a few scientists have been able to explore this amazing rift caused by the subduction of the Pacific Plate under the Mariana Plate.
3	3	"Krakatoa"	February 24, 2009
A look at the geologic history of the Krakatoa volcano in Indonesia, the 1883 eruption which spawned a tsunami that took tens of thousands of lives, and how another, possibly more powerful eruption, could happen again.
4	4	"Loch Ness"	March 3, 2009
A look at the geologic history of Scotland and how the mysterious Loch Ness was carved out by the movement of ancient glaciers.
5	5	"New York"	March 10, 2009
A look at the geologic history of the land modern day New York City sits atop; how Ice Age glaciers carved the rock beneath the metropolis, and its connection to land on the east coast of Africa.
6	6	"Driest Place on Earth"	March 17, 2009
A look at the driest place on Earth, the Atacama Desert in South America which is 50 times dryer than Death Valley; and how even in such a barren place, bacteria can still thrive.
7	7	"Great Lakes"	March 24, 2009
A look at the Great Lakes of North America – the largest expanse of freshwater on Earth, and how findings gathered from a fossilized coral reef and the salt mines below the lakes are providing geologists with evidence that the region was once an ancient seabed.
8	8	"Yellowstone"	March 31, 2009
A look at Yellowstone National Park and the caldera super volcano beneath it that is pushing up the land and long overdue for what could be a titanic eruption.
9	9	"Tsunami"	April 7, 2009
A look at how tsunamis are created, and the possible consequences if a landslide generated megatsunami were to strike the east coast of the United States.
10	10	"Asteroids"	April 14, 2009
A look at how asteroids played a role in the formation of the Earth; a study of how the Barringer Meteor Crater in Arizona was formed, and why little evidence remains of the meteor itself that created it.
11	11	"Iceland Volcano"	April 21, 2009
A look at the geologic history of Iceland and how the forces of fire and ice – volcanoes and glaciers – played a role together in the island's formation.
12	12	"Hawaii"	April 28, 2009
A look at the geologic puzzle of how the isolated Hawaiian Islands chain was formed and predictions about their future.
13	13	"The Alps"	May 5, 2009
A look at the Alps mountain range in Europe; how geologic uplifting caused by the collision of the African and Eurasian plates brought such peaks as the Matterhorn and Eiger to their current height, and the marine fossil evidence found there that shows the land was once below sea level.

 

Season 2 (2009–10)

Series #	Season #	Title	Original airdate
14	1	"The Grand Canyon"	November 24, 2009
A look at how the Grand Canyon in Arizona was believed to have been formed by the slow draining of an ancient lake which formed the Colorado River and carved the canyon out over millions of years.
15	2	"Vesuvius"	December 1, 2009
A look at the geologic history of Mount Vesuvius which destroyed the ancient city of Pompeii; how geologists are collecting evidence that the volcano is stirring again; and how another eruption could spell disaster for the unprepared heavily-populated city of Naples.
16	3	"Birth of the Earth"	December 8, 2009
A trip four billion years back in time to show the formation of planet Earth; to how molten material came together and solidified into rock; how the world survived a collision with a Mars-sized planet; how water arrived and formed the oceans, and when the first lifeforms appeared.
17	4	"Sahara"	December 15, 2009
A look at the Sahara, the largest desert on Earth, and how scientists have uncovered fossilized evidence of whales, fresh water shells and ancient human settlements – clues that this searing wasteland was once a fertile land with a great sea.
18	5	"Yosemite"	December 22, 2009
A look at how the geographically diverse Yosemite Valley was formed, and the debate whether it was carved by crushing ice age glaciers or a volcanic ripping of the Earth.
19	6	"The Rockies"	December 22, 2009
A look at the mighty Rocky Mountains; how they are being formed by geologic uplifting from the collision of the Pacific Plate and the North American Continent, and the evidence that these geologically young mountains are still growing.
20	7	"Ring of Fire"	January 12, 2010
A look at the Pacific Ring of Fire – the largest region of volcanic activity on Earth, that stretches around the Pacific Ocean from New Zealand, to Japan, to the Aleutians and down through the Andes mountain range of South America.
21	8	"Everest"	January 19, 2010
A look at the geologic history of Mount Everest, the tallest peak in the world, and how the Himalayas mountain range was really once an ancient seabed, pushed up to the roof of the world by tectonic smashing of the Indian plate into the Asian continent.
22	9	"Death Valley"	January 26, 2010
A look at the geologic treasure trove of Death Valley; how one of the hottest places on Earth holds evidence for the coldest times on our planet; and how the valley, already well below sea level, is still sinking lower into the Earth.
23	10	"Mt. St. Helens"	February 2, 2010
A look at the creation of the Mount St. Helens volcano in Washington state; its history of violent eruptions and the evidence another massive eruption could occur again in the near future.
24	11	"Earth's Deadliest Eruption"	February 9, 2010
A look back 250 million years ago when a massive volcanic eruption, (in what is now Siberia), spewed lava one mile thick over an area the size of Texas; caused intense climatic change that killed 95% of the life on the planet and paved the way for the next dominant species – the dinosaurs.
25	12	"America's Ice Age"	February 16, 2010
A look at past Ice Age eras that Earth has experienced throughout its existence; how the slightest changes in the planet's orbit and angle of rotation can bring them about; how long they can last, and when the Earth will endure another.
26	13	"America's Gold"	March 2, 2010
A look at how gold, a scarce element left behind by the explosions of supernovas, was collected by the forming Earth and how its geologic processes concentrated it in various places throughout the globe.