A still more important question hinges on their geographical distribution. Nothing can be more unsafe than to found any important deductions on what is known on this subject at present. If all those which are described in books and in journals of learned societies were marked on a map, the conclusion would be that the most of them are found on the east coast of Ireland; a dozen or so in Waterford and Wexford; as many in Dublin and Meath, and an equal number in County Down. But this knowledge may merely mean that the east coast, possessing roads and towns, has consequently been more frequented by tourists and antiquaries than the remote or inaccessible west.
Among the records, however, of the Ordnance survey, and in the Du Noyer drawings, there are probably sufficient materials for the purpose. Both are deposited in the Library of the Royal Irish Academy at Dublin; but any person who would attempt to use these materials for the purpose of such an investigation, must be not only an enthusiast, but have his whole time at his disposal. The disarray in which they now exist renders them utterly useless to any ordinary student of Irish antiquities.
The Irish themselves seem to have only one tradition regarding their dolmens. They call them all "Beds of Diarmid and Graine," and that is the name applied to them in the sheets of the Ordnance Survey. The elopement of Diarmid with Graine, the daughter of Cormac Mac Art, whose date, according to the Four Masters, was A.D. 286, is one of the most celebrated of Irish legends.[256] The story is, that being pursued all over Ireland by Finn, the disappointed suitor, they erected these as places of shelter, or for hiding in. This is, of course, absurd enough; but it shows that, in the opinion of the Irish themselves, they belong to the period which elapsed between the birth of Christ and the conversion of the people to Christianity. There is no hint in any Irish book that any of them were erected before the Christian era, nor anything that would lead us to suppose that any are more modern than the time of St. Columba.
The most extensive group of free standing dolmens known to exist in Ireland, is that in or near Glen Columbkille, at the extreme western point of Donegal. No account of these has been published—so far as I know—in any book or journal, and I am indebted for all I know about them to my friend, Mr. Norman Moore, who paid a visit to the spot this autumn to obtain the information I wanted, and it is from his descriptions that the following is abstracted.[257]
The principal groups are situated in Glen Malin More, a small valley running parallel to that of Columbkille, about two miles to the southward of it. There are three groups on the north side of this valley and two on the south, extending from about half a mile from the sea-shore to about three miles inward. The finest group is that next the sea on the south side, and consists of six dolmens, situated nearly in a row, about 50 or 100 feet apart, and is accompanied by some cairns, but so small as hardly to deserve the name of Tumuli. The stones of the dolmens range from 6 to 12 feet in height, and their cap-stones are still there, though some have been displaced.
The second group, a little way up the glen, consists of ten dolmens arranged in two parallel rows, but they are neither so large nor so perfect as those nearer to the sea.
Nearly opposite the first-named group on the shore, but on the north side of the stream, are two dolmens so nearly contiguous to each other that they may almost be considered as one structure. About half a mile to the east of this is a fourth group, consisting of four dolmens, accompanied by cairns, and two at least of the former are of considerable magnificence. The group farthest up the glen consists of five or six dolmens, but all except one in a ruinous state.
The number of dolmens in Glen Columbkille is not given by Mr. Moore; but, from the context, there must be five or six, making up twenty to thirty for the whole group. So far as can be judged from the description, the group in Glen Columbkille seems to have better fitted and more complete chambers; consequently, I should infer it to be more modern than the others. It would, however, require careful personal inspection to classify them; though I have no doubt it could be done, and that, with a little care, these six groups could be arranged into a consecutive series, whatever the initial or final date may turn out to be.
The general construction and appearance of these tombs is that of the so-called Calliagh Birra's house in Meath, described further on ([woodcut No. 80]). From its situation and appearance, there seems little reason for doubt that the Meath example belongs to the fifth or the sixth century; and if this is so, as little for doubting that these dolmens in Donegal are of about the same age, or, in other words, that this mode of interment continued to be practised in certain parts of Ireland, especially near the coasts, down to the entire conversion of the inhabitants to Christianity.