Ball Peen Sledge Hammer

I am wondering if anyone can tell me what industries used a Ball Peen Sledge Hammer I have come across three recently but had never seen them before. One was a lightish weight maybe 7lbs at the Hand tool sale. The other is amongst the sledges at the smith I go to, and the third I bought at a market on the weekend and weighs about 20lbs.



I tried googling it to see if I could find if they were for a specific task or profession in the past. I know they could be useful for many things, but what were they made for.



Any hints???