LNER B1 4-6-0 No 61078 with K1 62041 on an up slow in Grantham station in 1951. Both locos are in full reverse gear, which could mean that either they have just backed onto the stock to couple up and take it forward, or they are preparing to propel the stock out of the platform. Looking at the trails of steam, and depending on the wind direction on the day, the train may even be moving slowly backwards.

Photo: T.G. Hepburn / Rail Archive Stephenson