14 



The Sheep-Fluke. 



ploughing two furrows of suitable uniform depth (say) 8 inches, and scooping 

 out the soil and piling it on the lower side of the race, to form a dyke, 

 which increases the carrying capacity of the race. 



It is better to locate the races by means of a surveyor's level, as when 

 done " by eye" the races are commonly made unnecessarily steep. A very 

 slight fall suffices if much rain falls, though a light rain is better handled in 

 steep races. A fall of 1 foot in 100 can scarcely be detected by the eye, yet 

 a race with that fall will carry water admirably when there is a good smart 

 shower. 



This matter of the fall in the races is one that will repay careful con- 

 sideration in locating tanks, because upon it depends in no small degree 

 every other detail of the tank. 



It is usual to locate tanks in natural depressions— so usual that it seems 

 to have become almost an accepted law that they cannot be located any- 



^r|^£=t^=r{i^- 



Fig. ll._The ploughed races a, b, intercept the water from rain-storms, and run it into the tank c, 

 whence it is siphoned into a trough near d, outside the fence. 



where else. This is, however, a mistaken idea, and anyone having to locate 

 tanks on a station, if he be not something of an engineer, would do well to 

 study the works of competent engineers as illustrated in the water supply 

 of the nearest large towns. 



While a natural depression is a model location for a tank, it is not a 

 necessity, and it must be remembered that to secure a suitable _ natural 

 depression the pastoralist may have to place his tank in an otherwise very 

 inconvenient or unhealthy position. The one necessary natural feature to a 

 tank is a sufficient watershed. Given a sufficient watershed, the remaining 

 features are a matter of engineering, and by engineering I do not mean 

 scientific engineering, but simply taking carefully into account the simple 

 fact that water runs downhill, and this other hardly less obvious fact, that it 

 is better to store water at an elevation than in the lowest places. 



However obvious these two principles may seem to the reader, I can 

 assure him that they are very largely disregarded throughout this Colony in 

 constructing tanks for watering stock, for it seems to be regarded as essen- 

 tial to place these tanks in the lowest possible places, and the axiom that 

 water runs downhill seems to be accepted only in case the hill is steep. 



