No. 4.] FUNGOUS DISEASES. 97 



it is an easy matter with this nozzle to deliver the spray 

 into the tops of the highest orchard-trees. For such work 

 the double Vermorel nozzle, so adjusted that the adjacent 

 sides of the two conical sprays will be parallel, is the best 

 device with which I am acquainted. The single nozzle sells 

 for $0.50; the double, for $1. An eight-foot, brass-lined 

 bamboo pole to carry the nozzle can be bought for $2. 



In order to maintain a constant stream and to deliver it 

 with sufficient power, a force pump is essential. These are 

 now made in many patterns by almost all manufacturers of 

 pumps. In my own work I have found that, when spraying 

 is to be done on a small scale, as in the greenhouse, a vine- 

 yard or potato field of an acre or less, and in gardens, some 

 form of knapsack sprayer, to be carried on the back and 

 shoulders, is serviceable. It consists of a copper tank 

 holding four or five gallons, and fitted Avith a small force 

 pump worked by a handle, which hangs over the shoulder 

 of the operator. The catalogue price of such an outfit, 

 with hose and nozzle complete, is about $12. A still 

 simpler and cheaper device, which I have used even in 

 orchard work on a limited scale, consists of a small pump, 

 costing $7, which is made to clamp firmly to the side of the 

 pail. By making use of a forty-pound candy pail, I have 

 found such an outfit fully as convenient as the knapsack 

 sprayer. For work on a larger scale, as in orchards, exten- 

 sive vineyards or potato-fields of two acres and upwards, a 

 large receptacle and force })ump are essential. In its usual 

 form such an outfit consists of a fifty-gallon cask (a kero- 

 sene barrel, for example), mounted on a low wagon and 

 fitted with a force pump of considerable power, made for the 

 purpose. Such a pump is usually provided with a double 

 outlet and two lines of hose, so that two rows of trees can 

 be sprayed simultaneously. The essential points to be noted 

 in a spraying pump are: (1) a good-sized air chamber, 

 sufiicicnt to maintain a steady spray for at least a minute, 

 without pumping; (2) all the working parts to be made of 

 brass, as Bordeaux mixture corrodes iron ; (3) the valves to 

 be of brass ; (4) a low head, so that the outfit may be driven 

 underneath fairly low-hanging branches; (5) an automatic 

 agitator, to keep the mixture thoroughly stirred. Pumps 



