If I may add, this is a french-style
doloire. Due to its relatively simple form I guess it is pretty late, circa 1900. The seam doesn't have to be arch-welded, it could be forge-welded but poorly executed. Older, finer
doloires are works of applied art, sometimes with forged decorations.
http://www.legreniersaintmedard.net/...ls/doloire.jpg