One of the 'Royal Engines' on a Hitchin bound goods train.

Peter Kerslake says "Cambridge allocated "Claud Hamilton" 62618 was invariably well kept as seen here, regarded as the "Standby" engine when sister engine 62614 from Kings Lynn Depot was unavailable for Royal Train duties on the line from Cambridge to Kings Lynn and the branch to Sandringham situated on the Hunstanton line.
That steel rim on the smokebox door looked most impressive as seen here when burnished with some steel wool or similar , and 62618 is one of the "Claud Hamiltons" having the attractive footplating between her driving wheels which made those of her class so equipped much more attractive in appearance than the ones without this feature."