Mechanical Appliances 581 



for any reason they should require adjustment, 

 the design of the machine is so simple that a 

 mere novice can remove the pumps, and take 

 out and replace the valve in less than half a 

 minute, which is a consideration of the utmost 

 importance. 



The machine illustrated on p. 580 is a very 

 handy type for use on plantations where the 

 growth is very close. They are constructed in 

 any size to contain from 12 to 100 gallons each. 



MESSRS. WEEKS' KNAPSACK SPRAYER. 



Two poles or bamboos put through staples pro- 

 vided for them enable the apparatus to be 

 carried about by a couple of men or boys. The 

 machine can be fitted with one or two hoses 

 and nozzles as may be required. 



These machines are very cheap to work as 

 they do not require skilled labour to use them, 

 provided the overseers take care to see that the 

 spraying is thoroughly done. A large acreage 



