What is it?

This unusual contraption serves as a planter outside a house in Cardigan. It's made of cast iron and clearly old. I've never been able to decide what its original purpose was: a means of distributing soup around a workhouse or a device for collecting nightsoil? Could it have been equipment for an early mobile laundry service or part of a Victorian fondue set?

My best bet is that it was used in an industrial setting, perhaps a smelting pot with a trolley to move it from one part of an iron works to another. The struts seem to be designed to hook on to something for stability and the vat can be lifted off. Try as I might I cannot find anything similar depicted.

Does anyone have any better ideas or perhaps know for certain what it is? I'd love to solve the mystery.