WHEAT AND ITS PESTS. 9 



which the long spiral is rotated in the correct direction for 

 working, the wheat being delivered along its full length to the 

 receiving boot of the elevator, and also to the separators. 



The separators consist of two sets of jig screens, each set 

 having upper and lower screens, the upper being fitted with 

 coarse screen plates, removing " white-heads " and large 

 particles, the whole grains passing through. The lower screen 

 plates are of fine mesh, removing weevil dust, dead weevils, 

 and small screenings ; the whole grain tailing over the end. 

 The separators are also provided with aspiration on both inlet 

 and outlet ends, all fight material being thereby drawn off and 

 collected in a cyclone collector. 



The sterilized and cleaned grain is then delivered into an 

 elevator, which in turn passes it to the silo where it is bagged 

 off and delivered to the trucks. The bagging off floor is placed 

 at a convenient height above the rail level to allow of shooting 

 into the trucks below. 



The boiler is provided for supplying steam to the sterilizer 

 and also to the engine for driving the plant. The boilers have 

 a capacity of from 3,000 to 4,000 lbs. steam per hour at 100 lbs. 

 steam pressure ; suitable hot and cold water tanks with feed 

 pump and injector are provided for feed purposes. 



The engines are of the long-stroke, slow-speed, horizontal 

 type, arranged to drive through belt drive. The whole of the 

 plant is housed in a building of substantial design, the floor 

 being concreted throughout to facilitate cleaning and to 

 reduce the risk of fire. 



The plant is capable of treating 1,000 bushels per hour, 

 or approximaetly 2,500 bags per shift of eight hours. The 

 work is carried on in three shifts on many of the plants. Up to 

 the present about 500,000 tons of wheat have been sterilized, 

 and the probabilities are that half as much again has been 

 dealt with by the various States in Australia. 



All the weevils, together with their eggs and larvae, are 



B 



