Barrows, or mounds, of stone are of frequent occurrence. They are of very simple construction. The interment, whether by cremation or otherwise, having been made in a natural or artificial cist, or simply laid upon the natural surface of the ground, rough stones were placed in a large circle around it, and an immense quantity of stones were then piled up to a height of several feet. Some of these cairns are of very great size, and cover a large area of ground. Sections of two tumuli of this description are given in figs. 4 and 5. The cairn of stone was, as will be seen, covered to some depth with earth; perhaps in some instances this might be a part of the original design, but in most cases the soil which now covers these stone barrows may be traced to the ordinary process of decay of vegetation in successive ages. [Illustration: Fig. 4.] [Illustration: Fig. 5.] Barrows were not unfrequently surrounded by a circle of stones, set upright in the ground. These circles, in many instances, remain to the present day in different parts of the kingdom, and, the barrow itself having disappeared, are commonly called by the general appellation of “Druidical circles.” But of these, later on. The construction of the stone circles varied considerably. In some instances the upright stones were pretty close together; in others, wide apart; and in others, again, the spaces between the uprights were filled in with a rude loose rubble masonry, which thus formed a continuous wall. Some tumuli contained stone chambers and passages, formed of massive upright slabs, and covered with immense blocks of stone. Over these chambers, etc., the mounds of earth, or of stone, or of both combined, were raised, as will be hereafter shown. Interments in the Celtic grave-mounds were both by inhumation and cremation, and the modes of interment, in both these divisions, was very varied. Where inhumation obtained, the body was sometimes laid on its side, in a contracted position; at others, extended full length on its back or side; and in other instances, again, was placed in an upright sitting or kneeling posture. Occasionally, too, where more than one body has been buried at the same time, they have been laid face to face, with their arms encircling each other; at other times an infant has been placed in its mother’s arms. When cremation has been practised, the remains have either been gathered together in a small heap on the surface of the ground--sometimes enclosed in a small cist, at others left uncovered, and at others covered with a small slab of stone--or wrapped in a cloth or skin (the bone or bronze pin which has fastened the napkin being occasionally found), or enclosed in cinerary urns, inverted or otherwise. In some instances, even when placed in urns, they were first enclosed in a cloth. These are the general characteristics of the interments of the Celtic period, and they will be best understood by the following examples.