Did you know...

In the 19th century, one type of scavenger in London were the "pure finders": "pure" is another word for dog feces. They would scavenge dog feces from the Thames (which was, at the time, a giant sewer) and sell it to tanners, who would use it to clean leather.

Not a precise picture of a pure finder, but a mud lark, another scavenger of the Thames.
Picture from London Labour and London Poor (1861)
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