Note from the editor of the electronic version.

The maps have been scanned at 300 dpi. Use of the scales on the Key page is unlikely to be accurate. Click on the index maps to go to the high resolution scans.

To obtain a usable scale from your computer monitor or prints, use the Latitude grid scales at the sides of the maps (not the Longitude scales at the top and bottom - why not is left as an exercise for the student). Each black or white segment is two minutes of latitude or two nautical miles. A nautical mile is approximately 1.15 statute miles or 1.85 kilometres, and if you can construct a scale accurate to three significant figures, good luck to you.

The scans are largely untouched. Three folios have been slightly repaired from an ink blot, some slight stains of what appears to be tea, and attempted repair of a minor tear with adhesive tape. An appeal to untrained restorers of old documents - do NOT use proprietary transparent (or indeed any) adhesive tape to mend repairs; it very quickly discolours, becomes tacky, and ruins the paper and anything on the surface. If repair is essential, use paste and tissue paper (hard tissue - not soft paper handkerchief or similar); look up how to do the job properly.