"Having heard these words of the messengers, Saint Columba sent two of his companions to the king, with the pebble which he had blessed, and said to them; 'If Brochan shall first promise to free his captive, immerse this little stone in water and let him drink from it, but if he refuse to liberate her, he will that instant die.' "The two persons sent by the saint proceeded to the palace and announced the words of the holy man to the king and to Brochan, an announcement which filled them with such fear, that he immediately liberated the captive and delivered her to the saint's messengers." The stone was then immersed in water, and in a wonderful manner, and contrary to the laws of nature, it floated on the water like a nut or an apple, nor could it be submerged. Brochan drank from the stone as it floated on the water, and instantly recovered his perfect health and soundness of body. "This little pebble (adds Adamnan) was afterwards preserved among the treasures of the king, retained its miraculous property of floating in water, and through the mercy of God effected the cure of sundry diseases. And, what is very wonderful, when it was sought for by those sick persons whose term of life had arrived it could not be found. An instance of this occurred the very day king Brude died, when the stone, though sought for with great diligence, could not be found in the place where it had been previously left."[224] In the Highlands of Scotland there have been transmitted down, for many generations, various curing or charm-stones, used in the same manner as that of Columba, and reckoned capable, like his, of imparting to the _water in which they were immersed_[225] wondrous medicinal powers. One of the most celebrated of these curing-stones belongs to Struan Robertson, the chief of the Clan Donnachie. I am indebted to the kindness of Mrs. Robertson, for the following notes regarding the curing-stone, of which her family are the hereditary proprietors. Its local name is _Clach-na-Bratach, or Stone of the Standard._ "This stone has been in possession of the Chiefs of Clan Donnachaidh since 1315. "It is said to have been acquired in this wise. "The (then) chief, journeying with his clan to join Bruce's army before Bannockburn, observed, on his standard being lifted one morning, a glittering something in a clod of earth hanging to the flagstaff. It was this stone. He showed it to his followers, and told them he felt sure its brilliant lights were a good omen and foretold a victory--and victory was won on the hard-fought field of Bannockburn. [Illustration: Fig. 17. Clach-na-Bratach.]