The insignia on the uniforms at the fort reads FHG and stands for Fort Henry Guard. British regiments each had their own number and/or insignia which would be found on their buttons, knapsack and shako plate.
The pompom on a shako was not just there for decoration. Depending on the colour, one could tell the type of soldier and their training by the colour of their pompom: White pompom worn by grenadiers, the elite of the battalion, who usually led assaults. White over Red regular infantry of the line, trained to fight in the standard fashion. Green pompom light infantry, trained as skirmishers and snipers.
With these easily distinguished symbols, officers could determine quickly what kind of troops they were dealing with.
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