As I heared it, it was a poem about one disaster, ammended to suit another disaster, i suspect even changed and pulled about by everyone. We have recently recorded it and have been castigated in a review for attributing it to "Trad." although it came back from MCPRS as "In the Public Domain" which, to my constant ear bashing, does not mean traditional. Although we sang it at the South Street Shanty sing in NYC and were asked why the chorus had the line "from Yarmouth DOWN through Scarborough many hundreds more......" The only reasonable explanation I have for this is from the victorian age of steam when all the lines going to London were the up lines. However this is only a theory of mine and not dyed in the wool fact......discus!