a scraper of acquaintance with eccentric characters

[shootingstar]

With all my occupation, some six afternoons and two or three odd evenings remained at my disposal every week: a circumstance the more agreeable as I was a stranger in a city singularly picturesque (i.e. San Francisco; added by me). From what I had once called myself, "The Amateur Parisian," I grew (or declined) into a waterside prowler, a lingerer on wharves, a frequenter of shy neighbourhoods, a scraper of acquaintance with eccentric characters. I visited Chinese and Mexican gambling-hells, German secret societies, sailor's boarding-houses, and "dives" of every complexion of the disreputable and dangerous. I have seen greasy Mexican hands pinned to the table with a knife for cheating, seamen (when blood-money ran high) knocked down upon public street and carried insensible on board short-handed ships, shots exchanged, and the smoke (and the company) dispersing from the doors of the saloon.
(The Wrecker by R. L. Stevenson and L. Osbourne, chapter viii, published 1892)

Please, what do you take scraper to mean in this context?

 

[Piscean]

Someone who scrapes up an acquaintance.