APPENDIX 
CHEMICAL EXPERIMENTS WITH CARBON BISULPHID. 
The chemical Symbol of carbon bisulphid is CSz. Its mole- 
cules consist of one atom of carbon united with two atoms of 
sulphur. The specific gravity of the liquid is 1.29. The vapor 
is 2.63 times as heavy as atmospheric air. The pure article 
volatizes rapidly and completely when exposed to the air. The 
liquid boils at 115° F. 
The vapor takes fire in air at about 300° F. and burns with 
a faint blue flame, with difficulty visible in daylight, hut evolving 
considerable heat and decomposing the carbon bisulphid into 
carbon dioxide (COs) and sulphur dioxide (SO*). The latter 
is the familiar gas given off by the burning of sulphur matches 
and is a strongly suffocating poisonous gas, which should not 
be inhaled. Carbon bisulphid vapor mixed with three times 
its volume of oxygen, or an amount of air containing that amount 
of oxygen, forms a mixture which is very highly explosive upon 
ignition. As 21 per cent, of the air is oxygen, one volume of 
liquid carbon bisulphid evaporated in 5,357 volumes of air would 
form such a mixture. An atmosphere composed of one volume 
of carbon bisulphid vapor to approximately 14.3 volumes of air 
is liable to violent explosion in the presence of fire of any kind 
whatever, or a temperature of about 300° F. without flame. We 
have here about the maximum danger point from explosion 
in the use of carbon bisulphid. 
At the suggestion of the writer, the Division of Entomology 
requested information from the bureau of Chemistry of the 
Department of Agriculture on the following points: 
(1) Minimum proportional volume of carbon bisulphid vapor 
inflammable in air. 
(2) Minimum proportional volume producing an evident explo- 
sion. 
(3) Proportion producing most violent explosion and how 
violent. 
(4) Maximum proportional volume giving any explosion. 
(5) Temperature of ignition point. 
(6) Relative volume of vapor given by evaporation of one 
volume of liquid carbon bisulphid. « 
