A Scavenger was also a rubbish collector or nightsoil man, a person contracted to remove material from privies.
From the "Dictionary of Occupational Terms"
Category 970: General Labourers, or other unskilled workers.
Scavenger; see Sweeper
Sweeper; sweeper-up; scavenger; sweeps dust, dung, waste paper, leaves, ec., from surface of road or street and pavement, into heaps at the side of road with broom.......
From the OED. Scavenger
a. A person whose employment is to clean streets, by scraping or sweeping together and removing dirt.
c. fig. in various uses: One who collects filth; one who does ‘dirty work’;
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