121
intelligible. Useful objects are often made only in certain places whence they spread over a large area by means of trade. Thus, the people of the Papuan Gulf obtain their pots from the Motu and Koita round about Port Moresby and trade in pottery is also found among the Massim[1]. Again, in New Caledonia pots are said to be made only in three places[2]. The extermination of the people who made pottery by warfare or by some natural catastrophe might thus be limited to a small region and yet it might lead to the disappearance of the use of pottery over large and even remote regions. There is some reason to suppose that a catastrophe of a volcanic character may have led to the loss of pottery in the northern New Hebrides. The fragments of pottery found in Lepers' Island lay under two layers of soil, the deeper of which consisted of scoriae. In this region where volcanoes are even now active[3], it is possible that the use of pottery throughout an extensive region was wiped out by the destruction of some special people from whom the pottery was obtained. It is even possible that the pottery of Santo may have been introduced later into a region from which pottery had many ages before been eliminated by a volcanic catastrophe. We should have in such a case a combination of material and social factors. If pottery were once made in every island and district of the northern New Hebrides, it is very unlikely that any volcanic catastrophe would have wiped it out completely; but the limitation of the art to one district is a social factor which makes intelligible such an effect of the material agency. The material factor acting alone would not have abolished the art but in combination with the limitation of the manufacture to special
