My guess American made and made to use chaffing gel to burn and boil the water. The filler cap and safety valve(if its spring loaded to release steam pressure) is on the top. if its just a bolt its missing. There may have been a chimney over the top.

Never seen this one its an oscillating cylinder style engine.

You can find model info or model number or maker sometimes with websites online using the dimensions. Boiler diameter and height of engine and fly wheel diameter and base size are good measurements to know