the hill counties, it lias been found impossible to secure 

 Paris Green in the market. Not a single sample of London 

 Purple, could be obtained, a circumstance that indicated 

 that this insecticide was even less in demand than was the 

 case several years since. 



Commissioner H. D. Lane, through Maj. T. J. Key, very 

 kindly co-operated in securing additional samples of Paris 

 Green, and these with the samples already on hand enabled 

 the formation of a fair estimate of the character and quality 

 of the insecticides on the market in Alabama. 



The substance sold under the name "Paris Green" is, 

 chemically considered, an aceto-arsenite of copper, and is 

 known in the arts and to the trade under quite a variety of 

 names, such as, "Emerald Green," "Mitis Green," "French 

 Green," "Schweinfurt Green," etc. 



The last named term (derived from the place of it's first 

 manufacture) is the designation most frequently given to it 

 in Europe, it being there used largel}^ as a pigment on 

 account of it's brightness of color. 



Scheele's green, the simple arsenite of copper, is fre- 

 quently confounded with Paris Green, but it is distinguished 

 from the latter by its duller color and the entire absence of 

 acetic acid, which is a characteristic constituent of a genuine 

 Paris Green. 



One of the methods formerly employed in the preparation 

 of Paris or Schweinfurt Green involved the simple treat- 

 ment of the crude and freshly precipitated Scheele's green 

 (copper arsenite) with wood vinegar, from which source the 

 acetic acid of the final product was derived. 



The process as first devised by Russ & Sattler in 1814, was 

 kept secret for a long period, but after the investigation of 

 its composition by Liebig, its manufacture became more ex- 

 tended. 



In the method generally adopted for the preparation of 

 this substance, arsenious acid (white arsenic) and acetate of 

 copper (verdigris) are employed; both are dissolved separ- 

 ately in hot water, and the boiling solutions are mixed to- 



