LMS Rebuilt Scot 4-6-0 No 46148 The Manchester Regiment with the up 'West Coast Postal' . This photo appears in the Ian Allen booklet 'British Express Trains' Scottish Region. The caption is 46148 accelerates the WCP away from Aberdeen. It is not Nigg Bay, it's probably Cove Bay but it could be anywhere between there & Stonehaven. There is not enough detail to be more accurate.

Photo: W.J. Verden Anderson / Rail Archive Stephenson