3Borlase, William Copeland. The Dolmens of Ireland, Their Distribution, Structural Characteristics, and Affinities in Other Countries. Vol. 1. London: Chapman & Hall, Ld., 1897. 239-40.
According to Borlase, "Partially covered by a flat stone in the circle of stones which surrounds this monument was a spring of clear water at a distance of a few yards E. of the two pillar-stones." This book may be read in its entirety here.