http://www.lib.utexas.edu/usage_statement.html?maps=yes:
"Most of the maps scanned by the University of Texas Libraries and served from this web site are in the public domain. No permissions are needed to copy them. You may download them and use them as you wish. A few maps are copyrighted, and are clearly marked as such."
Public domainPublic domainfalsefalse
This file is in the public domain because it has been taken from a collection of public domain maps at the University of Texas Library
This template must not be used to dedicate an uploader's own work to the public domain; CC0 should be used instead.
This work must carry justifications for free usability in both the United States and its country of origin.