-------- Original Message --------
Subject: Re: Medieval 'projection'
Date: Thu, 19 Jan 2012 09:32:45 -0500
From: Joel Kovarsky <[log in to unmask]>
To: Maps, Air Photo, GIS Forum - Map Librarianship <[log in to unmask]>


On 1/19/2012 9:18 AM, Angie Cope, American Geographical Society Library,
UW Milwaukee wrote:
> Because it's meant to show directions as constant, it's a cylindrical
> projection,

I am not sure I understand you here. There were no cylindrical
projections at the time of the Catalan Atlas:
http://www.e-perimetron.org/Vol_3_4/Gaspar.pdf . That document was
something of a transition point between medieval mappamundi and portolan
charts (although there are specific earlier examples of portolan
charts). Whatever the case, it appears that the method of portolan
construction remains contentious.

          Joel Kovarsky