Ok, I'm studying the map now but can't find the 'you are here' mark....
all kidding aside a very good ref for conversation as I engage man made warming supporteres all of the time...they are fun to toy with before killing.

IIRC, the Admiral made this map from several (4 or 5) preexisting maps, a common practice. There are several errors that can be found on the map, (duplicate islands in different places) that point out known maps from the time, and common beliefs about certain unknown areas of the world. The map that depicted Antarctica is supposed to be the same source map that Columbus used to make his map for the voyage to find a new route to India. I do not remember if Columbus' map has been found, and I do remember that the original was never found.

IIRC (which happens less frequently these days, it seems) the topic of these maps "back in the day" when I cared about such things was that he had been given "info" from aliens. Somehow it all fit in with the drawings on the Plains of Nazca, the Atlantis Road (Wall) off Bimini, and "The Bermuda Triangle"!

I just figured he screwed up his map. Or something.