Adventures of Sherlock Holmes

Have a quote:

Pshaw, my dear fellow, what do the public, the great unobservant public, who could hardly tell a weaver by his tooth or a compositor by his left thumb, care about the finer shades of analysis and deduction!

–Sir Arthur Conan Doyle, Adventures of Sherlock Holmes, (Garden City, NY: Dolphin Books) p. 288.

I assume a weaver's tooth would be chipped from biting threads to cut them, but who knows what Victorian weavers were like.

Here's another:

One night–it was in June, '89–there came a ring to my bell, about the hour when a man gives his first yawn and glances at the clock.  I sat up in my chair, and my wife laid her needle-work down in her lap and made a little face of disappointment.  (p. 132)  

What sort of needlework?  Socks for Dr. Watson?  I used to think that needlework meant using a needle and thread as for embroidery but have since learned (primarily from looking at agricultural fair contest rules) that the term encompasses knitting needles and similar tools.