Strange stuff from Sheffeld

I'm reading through an e-text called REMINISCENCES OF OLD SHEFFIELD, compiled in 1872. As I'm mostly interested in the 1760s, there clearly will be no direct references, though some go way back. I'll share some as I go.

The image is from this site, which sells prints. and is of the Stagg works in Sheffield, but I haven't found a reference to that in the book.

But this book is a great example of things that were readily understandable once, but now aren't -- to me, at least. Can you help?

"The house at the top corner of Paradise square and Campo lane,
now a dram-shop, was, sixty years ago, a respectable grocer's shop, kept
by Mr. Newton (who was sueceeded by Mr. Benjamin Ellis), and at that
time was much celebrated amongst the grinders, both in town and country,
for the quality of the articles of emery, crocus, and glue.

WRAGG: Yes., that shop had almost the monopoly of the trade."

All right, a dram shop is a sort of pub, and I assume a grinder ground, which would fit with emery. But why crocus and glue? Anyone know?

Jo