If you can imagine sticking a cast iron manhole cover into the middle of a main road and a fifty tonne lorry ran over it and went through - it cracked and went through- you can imagine the consequences. So that was the time when we had to develop techniques in the metal melting process and we produced an iron which was known as ductile iron. This meant a change in the chemical processes which changed the carbon content. The carbon content in the cast iron was in a flake which was like a little fissure in the cast iron and that's where a cast iron would snap like carrot. Whereas the carbon in the ductile metal was turned into little spheroids - and at one time of day it was called spheroidal graphite iron - and this meant that instead of having little flakes of iron that could crack, you would have little spheroids of carbon in the cross section of the metal that wouldn't break at all.

(Jack Smith)

We then got into outside engineering castings as we called them, and at one time of day we were making motorcar crankshafts for Ford. That was great innovation because crankshafts had never been made in a sand mould before. They were made as I understand it in jigs of some sort.

(Jack Smith)