

CONTENTS. 



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 Introduction, ......................................................... 



I . Composition of lead arsenates found on the market ....................... 6 



Scope of the investigation .......................................... 



Methods of analysis ........ ........................................ 7 



Results of analyses ................................................. 9 



Discussion ......................................................... 11 



. II. "Home-made " lead arsenate and the chemicals entering into its manufac- 



ture ..... ...................................................... 12 



Introduction ...................................................... 12 



Methods of analysis ................................................ 



Lead salts ....................................................... 



Sodium arsenate ............................................... 



Composition of lead acetate ...................... 



Results of analyses ............................................. 14 



Discussion ..................................................... 15 



Composition of lead nitrate ..... ................................... 15 



Results of analyses .................................... ......... 15 



Discussion ..................................................... 15 



Composition of sodium arsenate ......................... 15 



Results of analyses ............................................. 15 



Discussion ..................................................... 16 



Theoretical composition of lead arsenate ............................ 17 



Published formulas ................................................. 19 



Directions for preparing lead arsenate .................. 



Comparative merits of lead acetate and lead nitrate .................. 22 



Physical properties of lead arsenate ................................ 



Ill . Action of lead arsenate on foliage ....................................... 24 



General discussion ................................................ 24 



Preparation of the lead arsenate used ........................ . ....... 26 



Experimental work of 1907 ......................................... 27 



Description of experiments .................................... 27 



Record of observations ......................................... 28 



Weather conditions ........................................... 29 



Summary for 1907 .............................................. 32 



Experimental work of 1908 ......................................... 33 



Description of experiments .................................... 33 



Record of observations ......................................... 34 



Notes made on June 4 ...................................... 34 



Notes made on June 9 ...................................... 35 



Notes made on July 29 on condition of fruit ................. 35 



Notes made on August 13 on condition of fruit ............... 36 



Weather conditions ........................................... 37 



Summary for 1908 .............................................. 41 



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