Essex, Herts & Middx
This is copied from Warburton's 1725 map, the principle difference being that his had 724 coats of arms around the margin.
Warburton had planned to cover England and Wales in large multi-county sheets, but only published Yorkshire plus this map.
Booksellers Overton and Bowles then jointly created this half-size reproduction (they also did one of Yorkshire, again copied from Warburton, and of Sussex, copied from Budgen).
Displayed scale of 20 miles = 212mm, or 2.4 miles/inch, and this is the actual scale as well, ie 1:150,000 (the 2nd map to get this distinction).