24 FARMERS BULLETIN 933. 



are worn out or broken they should be replaced. It is essential that 

 the valves be in perfect condition and these should be carefully 

 polished with emery dust or emery cloth. The valve seats if worn 

 should be changed, or new ones substituted. It may be that these can 

 be reamed out by a machinist. In case any gears are badly worn, new 

 ones should be obtained. The engine should, likewise, be carefully 

 gone over to see that it is ready for operation. If the cut-offs leak 

 they should be replaced or ground, and the nozzles and rods should 

 be carefully examined. In regard to the hose, it is always advisable 

 to have an extra lead, so that in case those in use leak badly the 

 spraying can proceed without delays. 



The insecticide or insecticide material for the entire grove should 

 be on hand at least a week or 10 days before operations are to be 

 begun. It is advisable that the quantity be carefully estimated, 

 and it is better to overestimate a little than to underestimate the 

 quantity, as in the latter case the spraying operations would have to 

 cease until another supply could be obtained. 



The source of water supply is also very important. For the oil 

 emulsions it is much better to use lake water, but if this is impossible 

 the water from the deep wells can be used and treated as heretofore 

 suggested. If sulphur sprays are to be used alone they will mix sat- 

 isfactorily with both lake and deep well water. Wherever practicable 

 the water should be hauled to the machine by a supply team (fig. 13). 

 Where two leads of hose only are being used, this hauling can be done 

 with one horse and a boy with two barrels, unless, of course, the 

 water supply is at a very great distance away. When four leads of 

 hose are being used, it will be necessary to use a double team and 

 four barrels or a supply tank. If the water for spraying is hauled 

 to the machine, instead of going to the water supply with the ma- 

 chine, the number of trees sprayed can be practically doubled. In 

 our operations we have sprayed as many as 18 loads of 200 gallons 

 each in 10 hours. When the water is hauled to the machine the tank 

 filler or suction pipe may be inserted into one barrel while the spray 

 men, with buckets, dip the other three barrels into the tank. This 

 saves much time in filling. 



Before any insecticide is used its strength should be known in order 

 to permit the dilution of the spray to the proper strength. In case of 

 the oil emulsions these should be diluted according to the percentage 

 of o'il they contain. The sulphur solutions should be diluted accord- 

 ing to the quantity of sulphur in each gallon of liquid, which is usu- 

 ally told by the degree of density as determined by the hydrometer. 



It is also of considerable convenience to be able to open a barrel 

 in the proper manner without breaking in the head. To do this take 

 an ax or other implement and pound first on one side of the bung and 

 then on the other. After a few such strokes the bung will be loosened 



