6 



The proportions of arsenious acid are also well above the 

 limit previously referred to (50^), and no traces of adulter- 

 ation or attempts at adulteration were detected. 



Sample No. 7, although of nearly the same shade of color 

 as a normal Paris Green, was nevertheless so lacking in the 

 brightness of tint which characterizes the genuine article 

 that it was at once regarded with suspicion. A qualitative 

 examination, carefully conducted, showed an entire absence 

 of both copper and arsenic, not the least trace of the latter 

 being discoverable by the employment of the most delicate 

 tests. Quite a number of tests were next made for all the 

 green coloring agents of importance, but with negative re- 

 sults, and it was then decided that the color of the material 

 was due to a combination of blue and yellow coloring 

 matters, 



A further examination revealed the presence of Prussian 

 Blue and chrome yellow, intimately mixed with each other, 

 and well incorporated with a large quantity of inert mate- 

 rials, such as clay, chalk, etc. 



On taking a small portion each of Prussian Blue and 

 Chrome Yellow and mixing with a large quantity of clay or 

 chalk, it was found that a product corresponding almost 

 precisely in color to the material examined, could be pro- 

 duced, and it was found quite easy to imitate the normal 

 shade of color of Paris Green, though, as before stated, the 

 brightness of tint, would be lacking. It was estimated that 

 a material of this character could be manufactured at a cost 

 not exceeding one cent per pound, while a high grade Paris 

 Green frequently costs above twenty cents per pound, the 

 fraudulent manufacturer being thus able to dispose of his 

 product at an enormous profit. 



Of course, such a preparation as this is entirely worthless 

 as an insecticide, and planters using such an article, and not 

 being aware of its character, would probably be thereafter 

 prejudiced against the use of insect poisons in any shape 

 or form. 



As before stated, the true character and quality of an 

 insecticide can be readily ascertained by analysis, and the 



