locality, the banks of the river Boyne, near Drogheda, in the county of Louth.
The author, after describing other interesting structures of dry-walled masonry of early date, gives a sketch of the progress of Architecture from the decline of the Roman Empire, and arrives at the period of the introduction of Christianity into Ireland, at the end of the fifth and beginning of the sixth century. Amongst the first stone edifices are to be noticed those interesting and very peculiar structures, the Round Towers, some of which are ascribed by Mr. Wilkinson to the early Christians, under the influence of the missionaries from other lands, who first evangelized Ireland at that early period. He appears to avoid reference to historical records, if indeed there are any upon which reliance can satisfactorily be placed, and grounds his conclusions upon the architectural character displayed in these monuments. Mr. Wilkinson, therefore, has investigated this subject in a different way from that in which it has hitherto been treated. The work contains a tabular statement, describing and shewing by lithographed drawings and numerous woodcuts, the constructive peculiarities, varied features, and present state of nearly every round tower in Ireland, with a description of the materials of which they are built. Some are of rough stones, ingeniously fitted together without mortar, and of very early character; others of rubble masonry, more or less rude; while others again are well built of ashlar masonry, with sculptured ornaments similar to those in general use in the 12th century.
Round Tower, Devenish Island.
The round tower on Devenish Island, county of Fermanagh, exhibits the form common to almost all these structures in their original state. Many round towers at the present day exhibit embattled tops, which are considered to be the work of a later period; many have doubtless al- together disappeared, and others are more or less in a state of decay. The general height of the towers in a perfect state varies from about 70 to 100 feet, their internal diameter, at the level of the doorway, measures about 8 to 9 feet; the walls are about 4 feet thick, and the door is usually placed from 8 to 10 feet above the surface of the ground; the doorways are either circular or square-headed, more usually the former; several openings occur between the door and the top of the tower, which are either square-headed, angle-headed or circular, generally either square or angle-headed, and of variable size; at the top, just below the
