Coal India 'Betty' The 2'0" gauge Coal India network in the North East corner of Assam used a number of small 0-4-0 'saddle tanks' built by W G Bagnall of Stafford. 'Betty' dating from 1931 was at work at Tirap mine on 24 January 1979. I think 'Betty' has long gone, but a similar loco 'David' still saw occasional use in 2010 at the nearby mine at Tipong.