To the long barrows of England answer in part at least the chambered cairns of Caithness and the Orkneys. The best known type is a long rectangular horned cairn (Fig. 4), of which there are two fine examples near Yarhouse. The largest is 240 feet in length. The chamber is circular, and roofed partly by corbelling and partly by a large slab. In the cairn of Get we have a shorter and wider example of the horned type. Another type is circular or elliptical. In a cairn of this sort at Canister an iron knife was found. On the Holm of Papa-Westra in the Orkneys there is an elliptical cairn of this kind containing a long rectangular chamber running along its major axis with seven small circular niches opening off it. The entrance passage lies on the minor axis of the barrow.
| Fig. 4. Horned tumulus at Garrywhin, Caithness. (After Montelius.) |
The megalithic monuments of Ireland are extremely numerous, and are found in almost every part of the country. They offer a particular interest from the fact that though they are of few different types they display all the stages by which the more complex were developed from the more simple. It must be remembered that most if not all the monuments we shall describe were originally covered by mounds of earth, though in most cases these have disappeared.
The simple dolmen is found in almost all parts of the country. Its single cover-slab is supported by a varying number of uprights, sometimes as few as three, oftener four or more. It is of great importance to notice the fact that here in Ireland, as elsewhere in the megalithic area, e.g. Sardinia, we have the round and rectangular dolmens in juxtaposition (Fig. 5, a and c).
| Fig. 5. Type-plans of (a) the round dolmen; (b) the dolmen with portico; (c) the rectangular dolmen. |
Occasionally one of the end-blocks of the dolmen instead of just closing up the space between the two nearest side-blocks is pushed back between them so as to form with them a small three-sided portico outside the chamber, but still under the shelter of the cover-slab (Fig. 5, b). A good example of this exists at Gaulstown, Waterford, where a table-stone weighing 6 tons rests on six uprights, three of which form the little portico just described. The famous dolmen of Carrickglass, Sligo, is a still more developed example of this type. Here the chamber is an accurate rectangle, and the portico is formed by adding two side-slabs outside one of the end-slabs, but still under the cover. This last is a remarkable block of limestone weighing about 70 tons. This form of tomb is without doubt a link between the simple dolmen and the corridor-tomb. The portico was at first built under the slab by pushing an end-stone inwards. Then external side-stones formed the portico, though still under the slab. The next move was to construct the portico outside the slab. The portico then needed a roof, and the addition of a second cover to provide it completed the transition to the simpler corridor-tomb. In many cases the Irish simple dolmens were surrounded by a circle of upright stones. At Carrowmore, Sligo, there seems to have been a veritable cemetery of dolmen-tombs, each of which has one or more circles around it, the outermost being 120 feet in diameter. The tombs in these Carrowmore circles were not always simple dolmens, but often corridor-tombs of more or less complicated types. Their excavation has not given very definite results. In many cases human bones have been found in considerable quantities, sometimes in a calcined condition; but there is no real evidence to show that cremation was the burial rite practised. The calcination of human bones may well have been caused by the lighting of fires in the tomb, either at some funeral ceremony, or in even later days, when the place was used as a shelter for peasants. A few poor flints were found and a little pottery, together with many bones of animals and some pins and borers of bone. The most important find made, however, was a small conical button made of bone with two holes pierced in its flat side and meeting in the middle. It is a type which occurs in Europe only at the period of transition from the age of stone to that of bronze, and usually in connection with megalithic monuments.