The system seems to have been mostly used by the British Expeditionary Force in France, although there is some evidence to suggest that it was used by at least some Commonwealth countries. It was also being used in the UK and Middle East although only isolated incidences of the latter have been found to date.
The following shapes and colour splits have been identified so far:
The above represents the HQ Battery. Different coloured bars were placed below the triangle to indicate the other Batteries. See below for the battery colour system.
Circle split vertically with 2 methods of showing the battery colour.
Circle split horizontally with 2 methods of showing the battery colour.
Squares and rectangles also appeared in different configurations.
Battery Identification Colours
There are 2 documentary sources for the colours although neither of them apply to the BEF. The first is from a book on the markings of 2 New Zealand Division in the Middle East and the other a document issued by British Troops Northern Ireland in January 1941.
The colours given in the first reference are:
Senior Bty – Green
Middle Bty – Yellow
Junior Bty – Light Blue
The colours given in the N.Ireland document are:
1st Bty – Green
2nd Bty – Yellow
3rd Bty – Light Blue
4th Bty – White
Although the first source is for New Zealand units, Commonwealth artillery tended to follow the UK marking systems. The second source used the colours as an additional bar below the Red/Blue AoS plate and not as a separate Tac Sign but they could well have been carried over from the earlier system.
As the 2 sets of colours concur it is reasonable to presume that these colours were those used for the geometric Tac Signs.
Photographic evidence shows that signals vehicles carried a white over blue rectangle above the Tac Sign. Whether this was just attached Royal Signals or all regimental signals vehicles is not clear.
Some units used letters and numbers to identify individual vehicles. These followed the same form as used on the later Tac Sign system.