Dear Bernard Cornwell
I am a long term fan and have all your books, many of which I have read several times.
I am currently reading The Fort which is excellent as usual. But I have difficulty in relating the movement of ships, troops and cannon to the map at the front of the book.
Looking at it more closely the compass bearings appear to be wrong – the river flows from the interior of the USA but according to the compass this is from the East when it is clearly from the West. So the Atlantic according to the compass is in the West and should be in the East.
Penobscot is North of Boston so the compass should point South when it actually points North. Canada and the Arctic are therefore incorrectly indicated to be  South of Penobscot. So North and South are also transposed.
Unless I have completely lost the plot!!!
Best wishes and I look forward to many more of your novels.
David Workman  Banbury, UK.