I have to say that 'The Manchester Angel' is my favourite recording of all time - and I had completely forgotten about 'Round Cape Horn'!
As a result of this thread I got the LP out and played it again (it's a wonder it didn't fall to pieces considering how much I played it when I was younger!). There, sure enough, is 'Round Cape Horn' and it all came back to me. Nevertheless, I still think it's the least successful track on the record and the tune is a bit dull and plodding - especially when compared with 'The Gallant Frigate Amphitrite' in the Penguin Book. Perhaps that's why I had forgotten it (?)