One of the rarest colonial era maps of Virginia is A new and accurate map
of Virginia wherein most of the counties are laid down from actual
surveys…by John Henry, published in London in February, 1770, by Thomas
Jefferys. Published cartobibliographies and descriptions of this map have
reported only one known state of the map. However, Al Gore's Great Internet
has allowed identification of an unrecorded first state of the map. You can
read about it here:

http://blog.ncmaps.org/index.php/john-henrys-1770-map-of-virginia/

Regards,
Jay Lester
in Ould Virginia