I am not following your maths... do you mean timeline?

Whall went to sea in 1860 and spent 11 years at sea. Near the end of his life he wrote a book about his time at sea and the songs he remembered. A contemporary who also went to sea at the same time, though for a far longer period of time, read Whall's book and found no problem with it.   

It is you saying silly things. "It was not possible for Whall to have collected the subject “shanty” when and where it is placed."

Please cite where you found Whall claiming to have collected a song from the northern California waterways. What he did say was that he sang the songs printed in the book onboard ships he was serving on, along with the rest of the crew. duh...   He was sharing meaningful memories, not off on a song collecting mission.

As for reference material use the Sibly Library of the world renown Eastman School of Music to download your very own copies of RR Terry's Shanty Books I & II. And read them.

https://urresearch.rochester.edu/institutionalPublicationPublicView.action?institutionalItemId=24944&versionNumber=1





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