NavList:

Frank,

       Thanks for the explanation. Good suggestion about looking for errors that might tie down the tables used. The only differences I saw between Worsley's logarithms and my own were in the last digit and I attributed to rounding. Maybe it warrants a closer look. Incidently  Worsley writes his logarithms to 5 decimal places. I wonder if this limits the possible sources or he is just rounding from 6.

You wrote: We can also assume Worsley knew how to tear pages out of books. Any traveler economizing on space knows the trick: rip out the pages you need, and burn the pages for the places you've already visited.

I considered the possibility of his taking partial volumes but I don't think that is what he did, at least not intentionally, given the expanded excerpt below.

“My navigation books had to be half-opened, page by page, till the right one was reached, then opened carefully to prevent their utter destruction. The epitome had had the cover, front and back pages washed away, while the Nautical Almanac shed its pages so rapidly before the onslaught of the seas that it was a race whether or not the month of May would last to South Georgia.” p.116

The books would be more likely to survive if they started out intact and he wasn't restricted by weight having complained about Shackleton's insistance on overballasting,

Regards,

Robin Stuart