But modern savages are but diminished shadows of the true primitives, and the ancient people of the Al Ubaid period exercised a mastery over the marsh to which the modern inhabitants never as much as aspire. Moreover, the people of the Al Ubaid period belonged to the most advanced group of the prehistoric farmers. Copper was used in their homeland for axes and adzes and even for mirrors. Bricks were known there, too; and brick buildings and the waterproofing of reeds with bitumen are certified for the period. It is likely that some reclamation and drainage of marshland was undertaken. In any case, the men of the Al Ubaid period appear from the first as cultivators, and we are free to imagine their fields as shallow islands in the marsh or as reclaimed and diked-in land. The vitality and power of these earliest settlers is astonishing. Their influence can be traced upstream, where their pottery replaced the Tell Halaf wares completely, even occurring in appreciable quantities in North Syria. Since it has nothing to recommend it as an article of export, we must assume that its makers came with it and settled widely throughout the upper reaches of Tigris and Euphrates. Nevertheless, the Al Ubaid people were simple cultivators like their contemporaries in Egypt and their predecessors in northern Iraq and Syria. This is most clearly shown by their inability to organize trade in order to obtain the copper which they had been accustomed to use in their country of origin. Once settled in Mesopotamia and removed from the sources of the metal, they used a substitute material that was locally available, making axes (Fig. 7_a_), choppers, and sickles (Fig. 7_b_) of clay which they fired at so high a temperature that it almost vitrified and thus obtained a useful cutting edge. These implements were, of course, very brittle and were broken by the hundreds. But they could be easily replaced; and the isolated settlements achieved that autarchy which is characteristic of early peasant cultures.