I and no doubt many others keep getting mixed up as to which "Foggy Dew" we are talking about. There is a delightful English song called The Foggy, Foggy Dew
about seduction and the perils of sleeping in the open in a damp English climate. The other is a sombre Irish song dealing with the Easter Rebellion in Dublin and the perils of "... Britannia's sons with their long-range guns".
I learned "The Foggy Dew" from Wilfried Drygala, of Idle Fellows fame, who sang it most beautifully in a haunting manner.