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TUTIRA 



spurs. Topping their undulatory crests, sheep pass to and fro from 

 their feeding-grounds ; a well-marked path climbs to the rise and dips 

 to the descent. It is at the bases of these loops that viaducts have 

 been built, each year increasing their height, as if the little builders 

 were deliberately taking thought of the morrow, scheming to save 

 themselves toil. The tools of the sheep are his toes, his sharp hoofs 

 act as gouges and chisels in the work; rain, sun, and wind, carrying 

 down silt and dust from the heights on either side, supply building 

 material ; the centre of the path constantly scooped out is as constantly 

 refilled. Though infinitely slow, there is no cessation in the raising of 

 the little embankment ; during storms the soft silt or liquid mud is 

 squeezed out on either side ; during droughts the trodden dust is hoofed 

 to right or left. Whatever the weather may chance to be, fair or rain, 



Sleeping-shelves. 



dry or wet, the even top-dressing of the embankment by dust or liquid 

 mud proceeds unceasingly. Its sides never slip or gap they are bound 

 together by a dense mat of Poa pratensis root. Of minute physical 

 surface-changes, none have been more entertaining to watch than these 

 viaducts. Some of them I have seen increase, inch by inch, until after 

 forty years their height has risen to a yard and a yard and a half. 

 The finished article, its close-nibbled verdant banks fed with rich dust 

 and silt, is a beautiful bit of animal architecture. 



Perhaps, however, of all surface modifications consequent on the 

 stocking of land, the most curious is the formation of sleeping-shelves, 

 ledges built by sheep themselves for their own convenience. Every day 

 sheep from every camp on the run spread to feed every evening they 

 return to sleep. Their instinctive desire is at night to lie on a summit ; 



