Fungous Diseases of Garden Plants. — 137 



the prevention of scab in the resulting crop. To prepare the 

 solution, get at the druggist's two ounces of pulverized corrosive 

 sublimate, empty this into two gallons of hot water, and let it 

 stand until it is all dissolved. Into a barrel put thirteen gallons 

 of water, and into this pour the two-gallon solution. After 

 some hours, during which time it should be repeatedly and 

 thoroughly stirred, it will be ready for use. Metallic vessels 

 should not be used to hold the solution. 



SPRAYING PUMPS. 



The Knapsack Sprayer. — As a spraying device for gener- 

 al garden purposes, the " knapsack " style has no equal. It is 

 not only a great convenience, but in 

 my estimation an absolute necessity 

 for every gardener of some preten- 

 sions. The illustration shows it in its 

 general arrangement. The tank should 

 be of copper. The kerosene attach- 

 ment, spoken of in preceding chapter, 

 will come handy, although it is not a 

 strictly necessary requisite. As to 

 nozzles, I prefer the improved Ver- 

 morel to all others. Certain further 

 improvements on the knapsack sprayer, 

 as for instance in the location of the 

 pump-handle, are yet desirable, and no 

 doubt will come in time. 



Knapsack Sprayer. 



The Barrow Sprayer. — This has 

 already been mentioned and illustrated 

 in the chapter on " Insect Foes." It is just the implement for 

 people who grow potatoes, egg-plants, and similar low-growing 

 garden crops by the acre. 



Other Spraying Devices. — Many of the cheap hand and 

 bucket pumps which you find advertised in the agricultural pa- 

 pers, will answer in an emergency, but their operation is less 

 convenient and less satisfactory every way. The knapsack is the 

 garden sprayer par excellence. 



Preventive Treatments. — First of all, the prudent gardener 

 will take precautionary measures against infection. Strict rota- 

 tion stands foremost. He will remove his endangered crops to 

 new fields, and as far remote as possible from infected ground. 

 In some cases he may be able to kill the winter spores by direct 

 applications of strong copperas solutions to dormant wood and 

 surrounding soil (as in the instance of grapevines, etc.), by wa- 

 tering the soil with weaker solutions, or by sowing powdered 



