There are some obvious features about this group of traditions, which at once lead to interesting questions. There is first the fact that all the British variants of the treasure stories centre round London Bridge; secondly, there is the extension beyond Britain to the Breton variant and the Norse variant, both non-British legends, of which the _locus_ is London Bridge. From these two facts it is clear that London Bridge had some special influence at a period of its history which dates before the separation of the Breton folk from their Celtic brethren in Britain, for the Bretons would not after their separation acquire a London Bridge tradition; and again at a period of its history when Norse legend and saga were fashioning. In the one case the myth-makers must have been Celts of the fourth century, and the only bridge known to these Celts must have been that belonging to Roman Lundinium; in the other case the myth-makers were Norsemen, and the bridge known to them was the later bridge so frequently referred to in the chronicle accounts of the Danish and Norse invasions of England. It is not difficult, by a joint appeal to history and folklore, to trace out from this very definite starting-point the events which brought about this particular specialisation of the world-spread treasure myths. Obviously the first point to note is that London Bridge loomed out greatly in the minds and understanding of people at two distinct periods of its history.[24] That the first period relates to its building is suggested by the date supplied by the evidence of the Breton version. The people who wondered at its building, or the results of its building, were certainly not the builders themselves, and we thus see a distinction in culture between the bridge builders and the wonder builders. This condition is exactly provided for by the building of the earliest London Bridge. It was a work of the Romans of Lundinium,[25] and the people who stood in wonder at this great enterprise were not the Roman engineers and builders, accustomed to such undertakings all over the then known world, and they must therefore have been the surrounding non-Roman people, who were the Celtic tribesmen. Now the culture-antagonism between the Romans of Lundinium and the Celts of Britain is, I believe, a factor of great importance,[26] though almost universally neglected by our historians, because they do not study the facts of early history on anthropological lines. Not only is it discoverable, as I think, from the facts of history, but the facts of tradition confirm the facts of history at all points. Thus I think it is important, if we can, to obtain independent testimony of the attitude of the surrounding people to the builders of London Bridge. We can do this by reference to the peasant beliefs concerning bridges, as, for instance, in Ireland, where on passing over a bridge they invariably pulled off their hats and prayed for the soul of the builder of the bridge,[27] and to the