²Cambrensis, Giraldus. The Topography of Ireland. (originally published 1187) in The Historical Works of Giraldus Cambrensis, Thomas Wright, ed. London: George Bell and Sons, 1882. 97.
The author continued: "Not that [the fire]cannot be extinguished, but the nuns and holy women tend and feed it, adding fuel, with such watchful and diligent care, that from the time of the Virgin, it has continued burning through a long course of years; and although such heaps of wood have been consumed during this long period, there has been no accumulation of ashes...As in the time of St. Brigit twenty nuns were here engaged in the Lord's warfare, she herself being the twentieth, after her glorious departure, nineteen have always formed the society, the number having never been increased. Each of them has the care of the fire for a single night in turn, and, on the evening before the twentieth night, the nun, having heaped wood upon the fire, says, 'Brigit, take charge of your own fire; for this night belongs to you.' She then leaves the fire, and in the morning it is found that the fire has not gone out, and that the usual quantity of fuel has been used."
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