The man was a blacksmith, one of the best in the North, because he had made a pact with the devil to make him so. With nothing but a file and a hammer, he could join two pieces of steel together seamlessly into a single piece of steel.

This is something physicists tell us is possible. Finely polished steel with perfectly squared ends can be matched end to end and struck with a hammer so that the molecules are "Jarred" across the tiny gap between the highly polished ends,- uniting the two pieces into a single whole.

Speaking of his strange powers, this blacksmith took a metal rod, and pounded it deep into a large rock with a single blow of his hammer. He said that whoever could remove the rod with his bare hands, had greater powers than he did.

As his fame spread, so did his popularity, and he eventually married.  To gain his powers though, his part of the pact with the devil was that he would give the devil his first born son.