My apologies for such a slow reply, but...
As a 'real ale' fan, I found the
W Blencowe & Co Ltd brewery in that picture of interest (I thought, I've not had a pint of
that one!). So I looked it up, and bam, we find this page (among others):
http://www.blencowefamilies.com/nl/261/261-05.htmSO, according to that page, the third William Blencowe died in 1888, then in 1889 it merged with Cannock brewery and it appears that it was known as "Blencowe Cannock Brewery" (I might be wrong on that one).
Is the chap on the left holding a number (on a spade) of "173"? Could the "1" of "173" be a reflection (like the edge of the board/sign/spade), making it a "73"? Or rather it looks like "173" been written onto the emulsion of the photograph as it was being developed.