The chief authority on the Bronze Age in Ireland belongs to the late Mr. George Coffey. In his book on the subject, "The Bronze Age in Ireland," he hesitates to date the close of the Stone Age and the introduction of the Copper Period as far back as 2500 B.C., which is the approximate date estimated by Montelius. He puts the close of the Copper Period between 2000 and 1800 B.C. and the first period of the true Bronze Age between 1800 and 1500 B.C. Now, according to the theory prevalent in Britain, the first Celtic invaders introduced the Bronze Age, and these were the Gaels or Goidels. If we accept this view and combine it with the best archæological authority, we shall conclude that the Celts reached Ireland at least 1,200 years before they are known to have entered Italy--that they pushed out to a distant island in the ocean more than a millennium before they occupied the fertile and attractive plains which lay on their very borders. But, it may be objected, is it not possible that the Celts of the Bronze Age had settled far away from the Alps, on the coasts of north-western Europe. Possible, perhaps, but what is the value of mere possibilities? We have seen it stated, and the Cambridge handbook is only a specimen of many publications that accept the view, stated most definitely that the Gaelic branch of the Celts introduced the Bronze Age to Britain and Ireland. Surely something more than a mere possibility, some shade or degree of probability should appear in support of teaching so positive. Now let us suppose that the dominant Bronze Age population of Britain and Ireland were Celts, as we are instructed to believe. Let us see what would follow from this position. It would follow, beyond question, that the peculiar art and works of the Bronze Age in Britain and Ireland would be mainly connected with the art and works of the Bronze Age in those parts of Europe which were likewise inhabited by Celts, rather than with other parts of the Continent. I cannot find that any such connection has been established or is believed in by archæologists. The Brythons, we are told, were Belgic invaders who introduced the Iron Age. Not the faintest probability has been brought forward to establish this very precise and positive doctrine. Coffey places the close of the Bronze Age in Ireland and the coming of iron into general use at about 350 B.C. It is admitted that the Celts of central Europe were in possession of iron about four centuries earlier. This affords a most cogent argument that, during the intervening four centuries, there was no such social and industrial continuity between central Europe and these islands as must undoubtedly have been if both regions and the intervening parts of the Continent had been occupied by Celtic populations.