10 



MASS. EXPERIMENT STATION BULLETIN 207. 



With commercial lead arsenate paste the results as shown in Fig. 4 are 

 much the same, though on the whole injury occurs before T and H get 

 quite as high as with the pure paste, particularly at the higher humidities. 

 The clear and cloudy weather lines are more nearly parallel than in the 

 other case. 



! 



Apple — Safety Lines for Spraying. 

 AB, clear weather; CD, cloudy weather. 



Humidi^i/ 



Pure acid lead arsenate 

 paste. 



Fig. 4. — Commercial acid lead 

 arsenate paste. 



Fig. 5. — Commercial acid lead 

 arsenate powder. 



/iu midity. 

 .~60 C ?p A ?0 



Clear: 7Vteit^ 

 Cloudy: d'O ■■ 



Fig. 6. — Pure neutral lead arsenate 

 paste. Crosses indicate cloudy 

 weather tests with no injury; 

 circles, clear weather tests with no 

 injury. 



