Jim Brittin:
Incidentally, I recall this station had diamond shaped platform name
signs which read 'ESSEX ROAD & [something]' but can't remember what.
Would it have been Canonbury?

Paul Terry:
I think it was the other way round - "Canonbury & Essex Road"

Leboff's "London Underground Stations abc" says it was originally
Essex Road, then Cannonsbury & Essex Road from 1922 to 1948, then
Essex Road again.

I think he might have the spelling wrong.
--
Mark Brader, Toronto "Yet Another Wonderful Novelty -- YAWN!"
-- Liam Quin

My text in this article is in the public domain.