74 
PRESERVING INSECTS. 
I apply it to black substances, and perceive that it 
leaves little white particles on them, I then make it 
weaker by adding alcohol. A black feather, dipped 
into the solution, and then dried, will be a very good 
test of the state of the solution. If it be too strong, I 
it will leave a whiteness upon the feather. J 
A preparation of arsenic is frequently used ; but 1 
it is very dangerous, and sometimes attended with i 
lamentable consequences. I knew a naturalist, by \ 
name Howe, in Cayenne,, in French Guiana, who i 
had lost sixteen of his teeth. He kept them in a 
box, and showed them to me. On opening the lid 
— " These fine teeth," said he, " once belonged to 
my jaws : they all dropped out by my making use 
of the savon arsenetique for preserving the skins of 
animals." I take this opportunity of remarking that 
it is my firm conviction, that the arsenetical soap can 
never be used with any success, if you wish to re- 
store the true form and figure to a skin. 
I fear that your correspondent may make use of 
tight boxes and aromatic atmospheres^ and still, in 
the end, not be completely successful in preserving 
his specimens from the depredation of insects. The i 
tight box and aromatic atmosphere will certainly do 
a great deal for him ; but they are liable to fail, for 
this obvious reason, viz. that they do not render, for 
ever, absolutely baneful and abhorrent to the depre- 
dator, that which in itself is nutritious and grateful 
to him. In an evil hour, through neglect in keeping 
up a poisoned atmosphere, the specimens collected 
by your correspondent's industry, and prepared bj 
his art, and which ought to live, as it were, for the 
