I now have the details from the 1904 certificate.
How old was Henry Hunt on that 1904 marriage cert? 29 year old
What was his occupation at that time? Boatman
Was his father definitely shown as William on the cert? Yes
What was William's occupation? Boatman
I think that Ricky hit the nail on the head with the Billinghay link, although I cannot find the family in the 1881 census. I will have to get his birth certificate before the price rise!
My only big question I would have would be when did he die? Did he die or just sail off in 1908?
Thanks to everyone who has contributed, you are so giving.