I have come across this profession on a shipping record for a chap I am researching. I have googled it and come up with an american website for a company which seems to have a british base in the 1700's but I'm not entirely sure this is correct! My man was in the late 1920's, so if anyone has any pointers as to where to go next or any ideas as to what the job actually was, I would be very happy to hear from you!
Andrea