Valley of the Black River. 37 



ness of the climate, and the violence of the winds 

 that prevail in summer, the new imported vegeta- 

 tion has proved but a sorry substitute for the old 

 and vanished. It does not grow large enough to 

 retain the scanty moisture, it is too short-lived, 

 and the frail quickly-perishing rootlets do not 

 bind the earth together, like the tough fibrous 

 blanket formed by the old grasses. The heat 

 burns it to dust and ashes, the wind blows it away, 

 blade and root, and the surface soil with it, in 

 many places disclosing the yellow underlying sand 

 with all that was buried in it of old. For the 

 results of this stripping of the surface has been 

 that the sites of numberless villages of the former 

 inhabitants of the valley have been brought to 

 light. I have visited a dozen such village sites in 

 the course of one hour's walk, so numerous were 

 they. Where the village had been a populous one, 

 or inhabited for a long period, the ground was a 

 perfect bed of chipped stones, and among these 

 fragments were found arrow-heads, flint knives 

 and scrapers, mortars and pestles, large round 

 stones with a groove in the middle, pieces of hard 

 polished stone used as anvils, perforated shells, 

 fragments of pottery, and bones of animals. My 

 host remarked one day that the valley that year 

 had produced nothing but a plentiful crop of arrow- 

 heads. The anthropologist could not have wished 

 for a more favourable year or for a better crop. I 

 collected a large number of these objects; and 

 some three or four hundred arrow-heads which I 



