CONTENTS. 



PAGE 



Materials ............ 2 



Pure acid lead arsenate paste ... ..... 2 



Commercial lead arsenate paste ....... 3 



Commercial acid lead arsenate powder ...... 4 



Pure neutral lead arsenate paste ....... 5 



Application ............ 6 



Adequacy of experimental methods ........ 6 



General results ........... 7 



The effects of temperature, humidity and light ...... 8 



Pear and elm ........... 8 



Apple ............ 8 



Cherry 12 



Plum 14 



Peach 17 



General conclusions .......... 18 



