Thanks for the references, it is a common conclusion colonial powers developed what they needed to extract the resources they wanted, not what the colony needed for general economic development. Interesting the line Morocco to Tunisia followed the coast, effectively duplicating the shipping route, then again further south was the Sahara and the Trans Sahara line was never completed.
Other rail notes,
In 1940 there were around 20,000 miles of track in the UK. Appendix X of "UK Inland War Transport" by C.I. Savage gives a detailed list of improvements done to UK rail lines during the war. It covers 5 pages, dates, company, cost and basic description of work. Costs vary from 1,000 to 257,000 pounds in the 3 pages devoted to projects started in 1939, 1940 and 1941. Almost all of these are marked as "Insurance", to provide emergency routes, bypasses in effect. They include lots of improvements to signals, passing loops, junctions, sidings and marshalling yard extensions.
India,
www.irfca.org
irfca.org
Capital Movement and Transportation: Great Britain and the Development of India's Railways Daniel Thorner The Journal of Economic History, Vol. 11, No. 4 (Autumn, 1951), pp. 389-402
The Pattern of Railway Development in India Daniel Thorner The Far Eastern Quarterly, Vol. 14, No. 2 (Feb., 1955), pp. 201-216
The first article indicates the following Indian rail track mileage, first line main track, year, miles,
1850 4,000
1862 10,000+
1902 25,000+
1924/25 38,000+
1929 41,000
"Since then there has been little change in the mileage for the sub continent" (page 391), 1947 40,500 first line main track, or 57,000 miles counting all tracks. Note Burma was part of India for statistics purposes until the 20th century,
Railways in India by J N Westwood says 1,000 miles of Indian branch line was dismantled during WWII. He also notes Burma had 2,060 miles of metre gauge lines.
Transport Development in India by S K Srivastava notes there was almost no track laid in the period 1930 to 1936 thanks to the depression. However 1,300 miles was laid from 1937 until sometime in 1939 or 1940 but that 2,000 miles of track in Burma was officially Indian until Burma was separated in 1937. So it would seem some track was laid but the definition of "India" was changed leaving the total about the same if you do not account for the Burma track. He claims total route mileage in India in 1939 was 41,156 miles, presumably main line track.
It was one of the big sources of friction pre war that the railways were giving poor service and largely owned by the British. Protests actually destroyed marshalling yards. The British largely reserved senior positions for non Indians, and most capital goods were purchased in England, meaning India missed out on the chance to develop the relevant manufacturing capabilities.
NW India,
Transportation Corps, Operations Overseas page 575, referring to the 1 metre parts of the Calcutta-Dimapur line,
"Railway construction further developed the line's capacity. By the end of 1944, approximately 20 percent of the railroad had been double-tracked, passing tracks were being extended, and the main railway yards enlarged. The work was performed by the British, often with the assistance of American bulldozers and earth-moving equipment."
US history, The Persian Corridor and Aid to Russia, page 331
"Before the Anglo-Soviet occupation the railway could haul 200 tons a day. During the period of all-British operation for which figures are available the daily average haul of Russian-aid freight was 661 long tons. The daily average haul in the peak month of British operation (September 1942) was 790 long tons of Russian-aid cargoes. In the period of interim Anglo- American operation (January through March 1943) the daily average of Russian-aid cargo hauled climbed to 921 long tons. The daily aver- age for the whole period of American operation (April 1943 through May 1945) was 3,397 long tons of Russian-aid freight. Nor was this the full measure of the capacity to which the ISR was brought. In the last five months of British operation, August through December 1942, the daily average of all freight hauled was approximately 1,530 long tons, a notable improvement over the capacity inherited by the British in 1941. For the whole period of American operation this figure rose to 5,336, an average which reflects not only the limited accomplishments at the beginning, but also the peak performance of 1944. The daily average for that year was 6,489 long tons, and for July, the top month of 1944, 7,520.2"