It is from its concluding part, however, that Bower's account derives its chief importance and its value as a contribution to the history of the development of the myth. "Something similar," he says, "happened at a later period, during the exile of St. Thomas, Primate of England, when the people of Rochester, intending it as an insult to him, docked his horse's tail. But their iniquitous action was foiled of its purpose and recoiled on themselves; for it was found that thenceforth all the children born in that place were tailed."[355] From this we first learn that a new character had by this time assumed a part in the story. Hitherto, the responsibility for having endowed Englishmen with tails had rested with St. Augustine alone. And his monopoly of the doubtful honour had endured through four centuries. Henceforth, though he was not to disappear altogether, he was to have a rival. In the case of Becket, as in that of his predecessor, there was a basis of historical fact on which to build up a legend. The chroniclers Ralph de Diceto, Roger de Hoveden, and both William and Gervase of Canterbury,[356] who record the murder of Becket, and whose proximity, in point of time, to the events that took place on those memorable December days of the year 1170, gives them indisputable authority, all agree in narrating, with such slight variations in matters of detail as serve to show that they did not merely repeat each other, an incident which happened to the Archbishop shortly before his death. They state that Robert Broc, a groom of the royal bedchamber, who, together with Nigel de Sacheville, incumbent of Harrow, was solemnly excommunicated by the Primate, on Christmas day, had cut off the tail of Becket's horse, as an insult to its owner. According to the two brother-monks, the Archbishop made direct reference to this indignity in his interview with the four conspirators, Reginald Fitzurse, Hugh de Moreville, William de Tracy, and Richard le Breton. "The tail of a mare in my service," he said, "has been shamefully cut off, as if I could be disgraced by the docking of a brute beast."[357] It was not, however, for this cowardly and contemptible act of spite that Broc was excommunicated, but because, being a layman, he had appropriated ecclesiastical revenues. And, though William of Canterbury records that the very dogs refused to be fed by the hand of the man whom the Prelate had banned, neither he nor any of the other chroniclers refers to the infliction of tails on him or his posterity. It was only at a later date, and when Broc had been lost sight of, as the perpetrator of the outrage, that the miraculous punishment was thought of.