Serious question, I used to say the distorted coastlines on old maps were just sloppy work, then a 1794 chart of the Chesapeake changed my mind | Antique Map Puzzlers - The Community Guide
Serious question, I used to say the distorted coastlines on old maps were just sloppy work, then a 1794 chart of the Chesapeake changed my mind
I always figured the weird bulges and squished islands on old charts were just bad drawing. Last Tuesday I spent three hours with a 1794 chart of the Chesapeake Bay at the library in Annapolis, and I noticed the same bulge shows up on four other maps from 1750 to 1810. That made me pull up a modern map and line up the rivers, and the bulge is really there, just smaller. The mapmakers were measuring with compass bearings and dead reckoning, so their errors piled up in the same spot over and over. Now I look at every wobbly coastline as a clue about whose survey it came from. Has anyone else traced one of these repeated mistakes back to a specific surveyor or expedition?
Man, I have to push back on this one, because a bulge showing up on five maps from the same era usually just means those mapmakers copied each other, not that the coast really looked that way. Plenty of old chart errors trace back to one bad source that got passed around, so the "same mistake" is more about lazy copying than careful surveying.