Is anyone able to confirm it is an oil-can?
Looks to me as if the chained lid doubles as a measuring cup, implying the contents were doled out accurately, which is rarely necessary with oil. My first thought was Rum, then disinfectant. Possibly oil for mixing into petrol to make two stroke.
Not so long ago, containers like this were made by the million out of earthenware, glass and tin-plate. Tin-plate cost more but sealed well, where lightweight, and could be knocked about without breaking. They had a multitude of uses, I think this one a bit special because ordinary lids were rarely chained.
I expect it was labelled and painted when new making identification easy. Then, in the past, someone cleaned it off to keep us amused!
Dave