From Mike Fell's collection, the sheds in 1950's with 11 locos, in the drydock is General Steam's PHILOMEL of 1936
Details given:
The nearest two locos are J72 68753 and 68747. Around this period there were about a dozen allocated, four J73, Five J77 and a single N13. 68747 spent periods at Alex Dock but in August 1954 she went to Heaton and ended her days at Tyne Dock in Oct 1961. 68753 spent most of her life allocated to the dock, transferring to Dairycoates in May 1954.