NavList:

I now had a chance to look up the references Keith gave. First thing: I have to correct myself: It wasn't Bedini, of course, who was wrong, as he is the editor of the 'Columbus Encyclopedia' and not the author of the quotes or of the Columbus myth.

The author of the quote crediting Columbus with discovering the circumpolar motion of Polaris is one Fred Kravath. He does not give any source for his contention and - judging from the literature he cites - he has no firm grasp of the history of navigation of that period.

The author of the second quote - which contradicts Kravath - is Michael Richey - former director of the Royal Institute of Navigation and a prolific writer about the history of navigation. His references to literature contain the relevant books by Portuguese and English authors dealing with early astronomical navigation. They show - by looking up and discussing the relevant sources - that the circumpolar motion was indeed known some time before "Columbus crossed the ocean sea".

So the claim that he discovered the circumpolar motion of Polaris is not surprising, it's simply wrong.

By the way: "regimento" does not apply to a table of the sun's declination, but simply means "rule (for)". There are several "regimento"s in the early portuguese navigation manuals: of finding the latitude by Polaris and by observing the noon height of the sun.

All this is superbly explained in the works of Luis de Albuquerque. I recommend "Astronomical navigation" and "Instruments of Navigation", both published in Lisboa 1988. And of course the first chapters in D.W. Waters " The Art of Navigation in Elisabethan and Early Stuart Times", London 1958, or his "Science and the techniques of navigation in the Renaissance", London 1976.

Wolfgang
----------------------------------------------------------------
NavList message boards and member settings: www.fer3.com/NavList
Members may optionally receive posts by email.
To cancel email delivery, send a message to NoMail[at]fer3.com
----------------------------------------------------------------