THIRSTY ANIMALS 133 



swallow-like flight, to the water is one of the sights of 

 the veldt in the dry season. ' Their machine-like 

 punctuality, and the wonderful displays afforded by 

 their enormous flights at the desert-pools/ form the 

 subject of one of Mr. Bryden's chapters in his recent 

 work on South Africa. ' The watering process is gone 

 through with perfect order and without over-crowding. 

 From eight o'clock to close on ten this wonderful flight 

 continued ; as birds drank and departed, others were 

 constantly arriving to take their places. I should judge 

 that the average time spent by each bird at and around 

 the water was half an hour. 7 A curious instance or 

 animal knowledge of the presence of water in un- 

 suspected places had a practical result in Holland. 

 The question of a supply of good water for the Hague 

 was under discussion at the time when the North Sea 

 Canal was being constructed. One of those present 

 remarked that there was water in the sand-hills ; that 

 the hares, rabbits, and partridges which swarm in the 

 sand-hills did not come to the wet ' polders ' to drink, 

 but knew of some supply in the ' dunes ' themselves, 

 and that he could name one or two places where he 

 had seen water. This idea was laughed at ; but one of 

 the local engineers present took the hint. The dunes 

 were carefully explored, and the result was the cutting 

 of a long reservoir in the centre of the sand-hills, which 

 fills with water naturally, and supplies the town. 



