Salt ranks next in value to, but a long way behind, gold and coal. The largest quantity is obtained by the evaporation of sea water along the coasts of the peninsula. Water from the Sambhar Lake, in a region of inland drainage in Rajputana, is also the source of a considerable supply. Rock salt is mined in the Punjab and in the North-West Frontier Province, the chief deposits being near Khewra in the Salt Range. Petroleum is found in the Tertiary strata of the Punjab and Baluchistan in the west, and of Assam and Burma in the east. Of a total output of 225,000,000 gallons in 1911, Burma contributed over 222,000,000. Here it is obtained at present in the dry zone of the Irrawaddy valley, but it has been located both to the north and south of that region. Although iron is worked only to a slight extent in India at the present time, large supplies both of magnetite and haematite are known to exist in the Archman rocks of Madras and the Central Provinces. Among other minerals which may be noticed are saltpetre, obtained in Bihar, rubies in Burma, mica in Madras and Bengal, and manganese in various parts of the country. India is now the chief producer of mica in the world, and ranks second in the production of manganese.
COMMUNICATIONS.—Much of the recent economic development of India is due to the construction of railways. Rivers had hitherto formed the chief means of transport, but, while those of the Indo Gangetic plain are easily navigable, the remainder are of compara tively little value to commerce on account of the rapidity of their courses. Road-building, on the other hand, has always been rendered difficult, in the lowlands by the absence of suitable material, and in the uplands by the irregular topography of the country ; and of the roads which were made many became impassable during the rainy season. Hence it was not until the advent of railways that facilities existed for the transport of heavy goods to or from the coast.
India now has over 33,000 miles of railway. The more important systems include the East Indian, whose main line runs from Howrah, opposite Calcutta, to Ambala in the Punjab, where it connects with the North-Western system and thus provides the great trunk route from Calcutta to Peshawar by way of Allahabad, Delhi, and Lahore. The East Indian Railway serves part of the fertile Ganges plain, and at the same time provides an outlet for other systems whose lines cover, as with a network, the remainder of the region. The North-Western Railway, which exports the wheat of the Punjab and North-West Frontier Province, runs from Karachi by Hyder abad to Multan, from which town there are lines to Peshawar, Lahore, and elsewhere. An important strategic branch of this railway follows the west bank of the Indus for a considerable distance, and is continued through Baluchistan by Quetta to Chaman on the borders of Afghanistan.
Bombay is brought into communication with the Ganges basin by several important lines. The Bombay, Baroda, and Central India Railway runs north by Baroda and across Rajputana to Delhi and Agra. The Great Indian Peninsular Railway has two routes from Bombay to the interior, the one crossing the Western Ghats by the Thalghat, and the other by the Borghat. The first of these routes goes by the valleys of the Tapti and Narbada to Jubbulpore, where it connects with the East Indian Iine to Allahabad, and constitutes part of the mail route from Bombay to Calcutta. A branch which breaks off at Bhusawal joins the Bengal Nagpur system at Nagpur, and provides a shorter but more difficult route to Calcutta. The southern line by the Borghat runs south east as far as Raichur, where it meets the Madras railway. These two routes from Bombay enable the Great Indian system to tap the wheat and cotton districts of the Deccan. The Southern Mahratta railway, with which it is connected at Poona and elsewhere, runs south to Mysore, west to Mormugao Harbour, the port of Goa, and east to Bezwada, near the mouth of the Kistna. The Madras Railway serves the southern part of India ; it runs along the west coast from Mangalore to Cochin, and then crosses by the Palghat to the east coast which it follows from Madras to Vizagapatam. Here it joins the Bengal-Nagpur Railway, the two main lines of which run from Vizagapatam to Calcutta, and from Calcutta to Nagpur. This railway shares with the East Indian much of the coal traffic of the country.
The Eastern Bengal system runs north from Calcutta, having as its territory the land between the Ganges and the Brahmaputra. An eastern extension is designed to connect with the Assam-Bengal line which runs from Chittagong through the Surma valley and across the Khasi hills to the valley of the Brahmaputra. Both lines carry jute, rice, and tea.
The chief Burmese railways start from Rangoon. One follows the valley of the Irrawaddy as far as Prome; while the other, making its way north by the Sittang, strikes the Irrawaddy at Mandalay, from which lines run north to Myitkyina, and north-east to Lashio. Teak and rice are the chief goods carried.
The difference in gauge on which, as a result of geographical and historical conditions, the chief lines in India have been constructed, is a serious drawback, which it has so far been found impossible to remedy. The East Indian, Bengal and Nagpur, North-Western, Great Indian Peninsular, and Madras lines are constructed on a gauge of five feet six inches, while the other lines which have been mentioned are on the metre gauge. Present railway policy in India is directed to connecting as far as possible the different systems which have the same gauge.