Maritime Dead Reckoning in the 17th Century

[@leoscheibelhut940]

JYF good work again, please keep the good information coming.

[@craigcollings5568]

Nice whipstaff you have there.

[@FreddyBarbarossa]

Very informative, great video thanks for sharing your work with us.

[@JYFMuseums]

We're glad you enjoyed it!

[@diamondtiara84]

Though the old methods were a lot of work, and a GPS makes things easier and more accurate, there's no sense of accomplishment, of having skills and using them well. With progress, you gain some things but lose others.

[@caseymccracken1535]

it's a 28 second sandglass, not 30! the ratio is 28\3600 to 48\6080 feet as it was in the day. This converts seconds per feet to nautical miles per hour without any math at all. Obviously the knots could be 51 feet for 30 seconds, but 48 is divisible by 6 (a fathom) and 8, which was a commonplace notion that is preserved today in inches, stock trades, or divisions of a mile: all eighths. I believe that the chip log or 'English' log appears in the 1570's

[@capuchinhelper]

The traverse board is fascinating, very thoughtful for someone to design tools specifically for illiterate people to use!

[@andrewwash8005]

Boat Swain? And your a sailor? How about Bos'in? As in Bos'insmate.