Describe the scabs working under Jurgis

From the text:

As very few of the better class of workingmen could be got for such work, these specimens of the new American hero contained an assortment of the criminals and thugs of the city, besides Negroes and the lowest foreigners—Greeks, Roumanians, Sicilians, and Slovaks. They had been attracted more by the prospect of disorder than by the big wages; and they made the night hideous with singing and carousing, and only went to sleep when the time came for them to get up to work.