456 Journal of Agriculture, Victoria. [10 Aug., 1918. 



which to irrigate the elevated part, a reservoir may be constructed in a 

 suitable position on the rise and filled with water pumped from a dam 

 conveniently placed down the slope. 



To facilitate the work of excavation a portion of earth to form an 

 inclining bank or ramp about 4 feet wide should be allowed to remain 

 in one corner of the reservoir, and over this the clay is drawn from the 

 excavation on to the embankment. This incline may be used as an 

 ingress and means of egress from the reservoir should subsequent further 

 excavation be necessary. It would also afford, if the embankment 

 were steep, a safe exit for the escape of animals that might fall into the 

 reservoir. 



Plate 172a is a drawing showing section of a reservoir, depicting the 

 formation of the embankments, position of the inlet pipe connexion with 

 the dam, outlet pipes and the water at its highest level. 



While the excavation is being made and the embankments built up, 

 the horses with the scoops, removing the earth from the bottom after 

 each successive ploughing, pass up the ramp and follow each other 

 around the top of the embankment. The earth is deposited where 

 required, and the continuous tramping, even if the clay be of only 

 average retentiveness, causes it to set firmly so that the banks almost 

 invariably h>ld the water satisfactorily 



The illustrations representing the dam and reservoir, as they appear 

 on the opposite pages, may be considered as one, and regarded as a longi- 

 tudinal section, showing the engineering principles involved in the estab- 

 lishment of this method of irrigation. As the water accumulates in the 



Plate 172. — Section of dam showing embankment and portion of outlet pipe, &c. 



dam during early winter it is pumped through the 2-inch connecting 

 pipe into the reservoir and stored there until the following summer. 

 When the reservoir has been filled and pumping ceases, the dam with 

 provision made for the overflow is allowed during late winter to accumu- 

 late water to its regulated holding capacity. The pumping site should 

 be near the dam as shown in the illustration, and when in an exposed 

 position, a windmill may be employed to operate an ordinary suction 

 pump. If the pumping site be sheltered, hoAvever, an oil engine with 

 centrifugal pump of sufficient power to lift the water to the desired 

 level will give more satisfactory results. 



In commencing to irrigate from the reservoir the land between the 

 level of the stand and horizontal pipes should be watered first from the 

 former and then the land below it from the latter. The land above 

 the level of the horizontal discharge might be watered by a hose attached 

 to this pipe, but experience would eventually prove the stand-pipe 



