159 
Mr. Webster said, that he felt that his experiments were sufficiently 
conclusive. 
The following paper was then read : 
FUMIGATION WITH BISULPHIDE OF CARBON FOR THE COMPLETE 
AND RAPID DESTRUCTION OF THE INSECTS WHICH ATTACK HER- 
BARIUM SPECIMENS, FURS, WOOLENS, ETC. 
By H. DU Buysson, Brout Fernet, France. 
The fumigating chest for use with bisulphide of carbon has been 
employed for many years in the preservation of unpoisoned herbaria, 
which would infallibly be devoured without this annual or biennial pre- 
caution. These fumigations may render great service in the preserva- 
tion of other objects more useful than the specimens of a herbarium. I 
shall describe, therefore, the first method used, and every one will know 
how to apply it to his own needs. 
DESCRIPTION OF THE FUMIGATING CHEST. 
It is in principle a rectangular box of light wood, lined with thin 
zinc, which is carefully soldered at all joints. Around the edge of the 
box, inside, runs a little gutter of zinc, carefully soldered. This gutter 
is filled with water and serves to make a water seal by means of the 
flange of the lid, which is also covered with zinc and carries all around 
a strip of the metal bent at right angles, and long enough to plunge 
into the water in the gutter. In this way the box is hermetically sealed 
and the vapors of the bisulphide cannot possibly escape from it. 
USE IN THE PRESERVATION OF HERBARIA. 
Botanists now generally poison their specimens, and the fumigating 
box is seldom used. Nevertheless it has served me well and I still re- 
sort to it from time to time, to preserve such plants as I have not time 
to submit to the action of arsenic in alcohol or to bichloride of mercury. 
The process in question is based upon the great volatility of bisul- 
phide of carbon at ordinary pressure and moderate temperature. The 
penetration of its vapor is so considerable that we have only to pile up 
in the chest the mounting- sheets of the herbarium, one above the other, 
in order to fumigate them. They are penetrated to the very center and 
eggs, larvae, and perfect insects, Anobiuin or Attagenus, are killed. Space 
should be left and right of the pile for the vessels containing the bisul- 
phide. Those which I use are of zinc and measure 10cm. long, Gem. 
wide, and 9cm. deep. There is no risk in prolonging the fumigation ; on 
the contrary there is but the greater certainty of its being efficacious. 
Five or six days will be time enough. No limit need be set to the quan- 
