They were built by Hudswell Clarke for the Mid-Suffolk Light Railway and were acquired by the LNER when it took over the Mid-Suffolk in 1924. Number 3 was withdrawn immediately and never received an LNER number. Nos. 1 and 2 were renumbered as LNER 8316 and 8317 respectively.
Dimensions
The dimensions for Nos. 1 and 2 are shown in the infobox (right). Dimensions for No. 3 are not known but it is believed to have been similar to No. 1, except that the cylinder bore was 14 inches (356 mm).
Allen, D. W.; Boddy, M. G.; Brown, W. A.; Fry, E. V.; Hennigan, W.; Manners, F.; Neve, E.; Proud, P.; Roundthwaite, T. E.; Tee, D. F.; Yeadon, W. B. (November 1970). Fry, E. V. (ed.). Locomotives of the L.N.E.R., part 8A: Tank Engines - Classes J50 to J70. Kenilworth: RCTS. pp. 68–70. ISBN0-901115-05-3.