I am very surprised at your comment on footplate rides in the works .The security was very very tight there .Patrol men (that's what Corby people called security men )would jump out even at the remotest parts of the works .I was on a visit to the works with the IRS (or it may have been RCTS ) on the 30/06/1956 ,32 loco's noted including Caledonian pug 628.On enquiring where the mines loco's were ,we were told they had a new shed along the Gretton Road. So the next day ,a Sunday ,a group of us push biked over to Pen Green loco shed. We propped our bikes up against the side of the shed wall,walked in a side entrance and obtained permission to look round .24 loco's present. We were just leaving when a patrol man ,seeing our bikes outside rushed in ,wanting to know what we were doing. I can still hear the man who gave us permission saying "Well they told us they were down at the works yesterday " Our names were taken and told not to enter S&L property again with out written permission. I met Eric Tonks several times on I R S visits ,I corresponded with him regular, giving reports on what I had seen. A very nice man ,but living in Birmingham he made very few visits to the East Midlands Ironstone field on working days. I don't know where he got the info' from about HE 2411 on test,I was told it was a standard Hawthorn Leslie, this was by the driver on the open wagon tour to Wakerley with No21 ( HL3931) in 1973.