The contention is that several lines of evidence point to the Sumerians, or certain groups of them, as being the traders who travelled the Mediterranean and the Atlantic coast of Europe in search of precious metals, and who are somehow responsible for the spread of the megalithic culture. Now, as we have seen, the Prospector is normally a merchant, we do not find him as a rule among miners and sailors, yet sailors must have accompanied these expeditions, and perhaps skilled miners also in some cases. It may be that the cult of the dolmen, or the rock-cut tomb which preceded it, belonged to one or other of these humbler peoples, perhaps recruited from the coast of Syria. Or it may be, again, that the Prospector, being unable to bury his dead after the fashion customary by the Persian Gulf, devised another plan more convenient for use in strange lands. The latter is, I am inclined to think, the more likely solution, since dolmens and other megalithic structures are found all round Sumer, in Syria and Palestine to the west[170], in the Crimea and the Caucasus.[171] Stone circles are found to the east in Seistan[172], while both these and dolmens occur further east in India. Time will show whether the suggestion, which I have put forward, that the Prospectors, who seem to have been responsible for introducing the use of metal into the west and north, to which they came in search of precious ores, started originally from the Persian Gulf, or whether, indeed they were but sojourners in southern Mesopotamia, having arrived there by sea from some more distant land, bringing with them the seeds of civilisation, as the legends of Oannes, the exalted fish-man, as given by Berosus, seem to indicate.[173] Be this as it may, there seems to be adequate evidence of a trade, starting in the eastern Mediterranean and going first to Malta and Sicily, and thence to Spain, Brittany, the British Isles and the Baltic. That the prime object of such trade was the procuring of gold, copper, tin and amber, seems equally certain, as does the fact that megalithic monuments are found associated with all the sites whence these commodities could be obtained, as well as upon the land routes connecting them. Further, a certain type of man, whom we term the Prospector, is found living in no small numbers in most of these megalithic areas, as well as becoming a successful merchant at many of the sea-port towns of Europe. Lastly we have seen that this trade, then in the hands of Babylonians, had reached the Mediterranean by 2800 /B.C./, was in touch with Malta, Sicily and Spain between 2600 and 2300 /B.C./, and scarcely later had reached Brittany, Ireland and the Baltic.