94 
the bottom of the large bottle, the stopper was removed by a 
sudden jerk of the string, the string was dropped in the large 
bottle, and it was quickly closed, the stopper being sealed in 
immediately with parraffin. This method of preparing the 
mixtures i_s more accurate than the one employed for the first 
series of experiments. The 5 bottles thus charged were allowed 
to stand for about three hours for the thorough diffusion of the 
vapor. At about the middle of this period the bottles were in- 
verted in order to facilitate the diffusion. The stopper of each 
bottle was then carefully removed and a small gas jet burning 
at the end of a glass tube was inserted in the bottle. The results 
obtained are indicated in the following table: 
Inflammability of mixtures of CSj with the air. 
No., 
Bottle 
Wt. CS 2 
per liter 
Wt. CS 2 
per 1000 
cubic 
feet 
Inflammability. 
1 
Grams 
0.0075 
Pounds 
0.47 
Not inflammable; slight odor of sulphur 
2 
.0182 
1 .14 
dioxid after removal of gas jet. 
No general combustion, a very small blue 
3 
.0461 
2.88 
mantle of burning carbon bisulphid 
formed around the gas jet. 
No general combustion; blue mantle of 
4 
.0805 
5.02 
burning carbon bisulphid formed around 
gas jet. 
Inflammable. 
5 
.1552 
9.68 
Very inflammable; very slight explosion. 
There was no general combustion except in the case of 
bottles Nos. 4 and 5. In the case of bottles Nos. 3 and 4 the 
result was very interesting. The mixture of the vapor with air 
was so dilute that the small gas jet introduced did not heat it 
hot enough to cause a general combustion, but a zone of combus- 
tion extended around the gas jet in every direction in the form 
of a blue mantle. It is worthy of note that the proportion of 
carbon bisulphid used in No. 3 (2.88 pounds per 1,000 cubic feet) 
is more than is ordinarily used in the fumigation of buildings. 
It must be remembered, however, that when small proportions 
of carbon bisulphid are used, the quantity in the air near the 
vessel containing it may be sufficient to cause an explosion if a 
flame is brought near it, or if the mixture be sufficiently heated 
by any other means. 
The experiments reported above were made with chemically 
pure carbon bisulphid. The third series of experiments described 
below was made with the commercial carbon bisulphid known in 
the market as "fuma,” which is largely used as an insecticide. 
As a comparison of the results will show, the inflammability of 
this commercial grade of carbon bisulphid is not essentially dif- 
ferent from that of the chemically pure substance. 
