Miller: up until introduction of the Bessemer process in the 1850s, the steel was "Cast steel"; the Huntsman hot-rolled crucible steel process of 1742 used for farm implements (like the L.C. Smith smile ). To form a pipe or barrel, a sheet was folded over a mandrel and the long edge hammer welded, leaving a "seam", lest Wonko has forgotten wink
Basic Bessemer had a C of .07 - .09%, but the 1881 study on the previous page lists .15 - .55%.
The Darby method of carburization was invented in 1890 to add carbon to steel, but there were earlier techniques
https://books.google.com/books?id=Fec9SNazAnwC&pg=PA61&lpg