Image and copy updated.

I have come across a wee bit of interesting history regarding communications from approximately 1200-1600 AD. Apparently, the Johnstouns of Wamphray built a signal hill in a direct line of sight with the tower at Lochwood castle, home of the Clan Johnstoun Chief. This allowed them to use signal fires as in a smudge pot or brazier that produced a lot of black smoke and flags to communicate rapidly with each other. One could say that it was an early warning system designed to signal impending raids and attacks, particularly by the English. It could also have been used to invite cousins and clan members over for a war council, a special celebration and a hearty meal of roasted beef and lamb washed down with freshly brewed beer. :-)

"In the British Library collection is preserved a map dated, on the reverse, Dec 1590 and entitled 'A platt of the opposete borders of Scotland to the west marches of England'. This had been kept in an atlas of Saxton's county maps that had belonged to William Cecil Lord Burghley, Elizabeth I's Secretary of State. This was made by, or by an attendant of, Edward Aglionby, a prominent member of the Cumberland gentry (see below). A note on the map states;
'The moste of these places on the Scotish syde are tower and stone houses, with some fewe plenashed Townes, as Dunfreis, Annand, Loughmaben, and such like; for the rest not put downe, they ar but onsetts or stragling houses, th' inhabitants followers of some of these above described. For those on the English Coaste, they are referred to the Tract lately sent to your L. of the Description of them in particular.' "

This map was obviously of military importance to the English. The Secretary of State of England did not commission such a detailed map of Scottish fortifications without some purpose in mind, as in another attempt to invade and conquer Scotland.

Having found this map online and having read the accompanying copy I took it into Photoshop, magnified it 600%, and found myself disagreeing with the description of it. So, I decided to color the various castles and fortalices according to the type of icon used, believing that there is a code of some sort here. Also, I have labeled some of the rivers to make orienting easier.

Here are the various castle and fortalice markings/colors.

Fortalices:
1) Green fill - plain circle upon a plain square,
2) Green fill - plain circle upon a square with a central dot,
3) Green fill - circle upon a square, both with a central dot,
4) Yellow fill - triangle upon a circle upon a square with a central dot,
5) Yellow fill - triangle upon a circle with a central dot upon a square with a central dot,
6) Blue fill - mast upon a circle upon a square with a central dot,
7) Blue fill - mast upon a circle with a central dot upon a square with a central dot,
8) Red fill - cross upon a plain circle upon a square with a central dot,
9) Red fill - cross upon a circle with a central dot upon a square with a central dot, and
Castles:
10) Orange fill.

Has anyone done a study to show if such a smoke or flag communication system was possible among these castles and fortalices? Are any mentioned in the history books? If so, which books? If not, I find this to be a very intriguing research project...

Now to break the code as to what these structures were built like, or how they were manned. I feel certain that there is such a code imbedded within the diagrams. IMO, there would be no other reason or need to be so careful in drawing such distinctive icons. What military intelligence is contained herein???

This raises several additional questions.
1) Did other castles and fortalices in Scotland, particularly in the West March, use a similar signal-tower method of communication?
2) If so, which ones and where?
3) Were there other signal hills built separate but close to castles and fortalices? If so, where?

Note, I have "cleaned up" digitally some parts of the map, and I