Near many of the monasteries the monks began to erect tall Round Towers in the beginning of the ninth century, as a protection against the Danes. They were built with several stories, each story lighted by one little window, and reached by a ladder inside. The door was small, and was usually ten or twelve feet from the ground. The moment word was brought that a party of Danish marauders were approaching, the monks took refuge in the tower with all their valuables and a good supply of large stones, and barred the door and windows strongly on the inside, so that it was impossible to get at them during the short time the robbers were able to stay. In fact the Danes were generally afraid of their lives to approach too close to these towers; for if one of them ventured near enough, a big stone, dropped by one of the monks from a height of sixty or seventy feet, was likely enough to come down right on his skull and make short work of him. We have still remaining many of these old towers. There was a spring well beside every monastery, either that, or a stream of pure water. The founder never selected a site till he had first ascertained that a well or a stream was near. These fountains served the double purpose of baptising converts and of supplying the communities with water. In most cases they were named after the founders, and retain their names to this day. It has been already stated how the early missionaries often took over the wells the pagans had worshipped as gods, and devoted them to Christian uses. We have now Holy Wells in every part of Ireland, and it is with good reason we call them so, for they preserve the memory, and in most cases the very names, of those noble old missionaries who used the crystal water to baptise their converts. We ought to make it a point, so far as lies in our power, to take care of these holy wells, and to keep them neat and clean, and in all respects in a becoming condition; and also to preserve their old names as our fathers handed them down to us. If there could be such a thing as grief in heaven, an old Irish missionary would certainly feel grieved to look down on the little well he loved, and used, and blessed, now lying unnoticed and neglected.