PARIS-GREEN. 7l 
being well-known manufacturers and great exporters of Paris-green to 
the United States of America and Canada. 
In reply to my enquiries, Mr. J. Dixon (Manager) wrote me on 
December 31st, 1889:—“Emerald-green, Paris-green, Scliweinfurth- 
green, are different names for the same thing. The first name is 
English, and is the one used in most of our Colonies, India, and 
China. The second is the American term. The third only used in 
Germany, and by German traders. 
“ Emerald- or Paris-green is a double salt of arsenite and acetate of 
copper—in other words, an aceto-arsenite of copper. You may take 
the U.S.A. analysis of Paris-green as correct. Provided Paris-green 
be pure, the analysis of different makes should be all alike, as it is 
a true chemical compound. 
“ The pure article (which is that used as an insecticide) is a true 
crystal, and varies in colour from a deep to a pale green, according to the 
size of the crystals. Both sorts are used, and we should think the pale, 
small crystal the best for this purpose. 
“ The dark shade is almost universally preferred, and commands a 
higher price. The reason probably is that this colour is of itself a 
guarantee of the purity of the article, as the reduced or adulterated 
qualities are all either pale or of a very bad colour. 
“As the pure pale is of a finer form, it would go further in use, 
and, when mixed with water, would keep up better.”—J. Dixon, 
Manager to Messrs. Blundell & Spence, Hull. 
With the information Mr. Dixon forwarded me samples of the dark 
and paler shade of Paris- or emerald-green, and also of the pale shade 
reduced about five per cent., with the observation that, if paler than 
this last, it should certainly be rejected. It is difficult to give an idea 
of tint by description, but perhaps to say that the desirable colours were 
a slightly darker and lighter shade of the colour called Apple-green 
would come fairly near. 
In reply to some further enquiries on my part, Mr. Dixon favoured 
me with some special details. In his first communication he had 
furnished me with the precise chemical formula of composition of 
Paris- or emerald green, but subsequently replaced this (as being a 
more desirable form of statement for the present purpose) with the 
following percentage analysis of pure emerald-green :— 
“ Percentage Composition of Emerald-green :— 
Copper 
Per cent. 
32-11 
Arsenic 
28-56 
Oxygen 
32-48 
Hydrogen . 
0-76 
Carbon . \ 
6-09 
Total ' . 
100-00 ’ 
