CAEBON- DISULPHID AS AK INSECTICIDE. 5 



fore^ should not he poured directly upon goods that would slioio 

 stains or upon food materials, although the vapor from it will not do 

 them harm. , . 



Liquid carbon disulphid is not at all explosive, and there need be 

 no fear in handling it if the cans are perfectly tight. It boils at 

 115° F., which is about the highest temperature of water in which 

 the hand can be held. One volume of the liquid is said to produce 

 about 375 volumes of the vapor. The liquid weighs a little over 10^ 

 pounds per gallon at ordinary temperatures. 



VAPOR PROPERTIES. 



The vapor of carbon disulphid is two and sixty-three one-hundredths 

 times as heavy as air, and therefore can be poured from one glass to 

 another, almost like water. The vapor easily can be seen flowing 

 down over the edge of an open vessel containing the liquid. It dif- 

 fuses rapidly through the air, as can be perceived from the spread of 

 the odor, but as it tends always to work downward rather than up- 

 ward, the vapor is more dense and has greater killing power at the 

 lower levels. This point has an important bearing upon the appli- 

 cation of the material. The vapor appears to have greater penetrative 

 power than does that of any other volatile liquid that has been tested 

 in insecticidal work. This power is far greater than that of hydro- 

 cyanic-acid gas, which is another fumigant frequently us-ed. It is 

 possible, therefore, to use carbon disulphid with good results for the 

 treatment of materials which would not be penetrated by other fumi- 

 gants under natural atmospheric conditions. The expansive tendency 

 is so great that the vapor may exert a pressure of several pounds to 

 the square inch in the container if the temperature of the liquid is 

 increased. The vapor is highly inflammable and explosive when 

 mixed with air in certain proportions. 



EFFECTS UPON HUMAN BEINGS OF INHALATION OF VAPOR. 



The gas is rated as highly poisonous, producing giddiness, vomit- 

 ing, congestion, coma, and finally death. These are, of course, its 

 extreme effects. In its ordinary use on a large scale in the fumiga- 

 tion of mills, warehouses, etc., where the worker may be exposed to 

 inhalation of the fumes for some time, only those effects which pre- 

 cede giddiness are likely to be felt. The first appreciable effect is 

 the perception of a very disagreeable odor, but this odor gradually 

 ceases to be noticed, showing that the sense of smell has been dead- 

 ened. Workmen may even question the fact that they are handling 

 the same material as at the start. The other senses seem to become 

 benumbed simultaneously, so that the operator does not realize that 

 anything is the matter with him. The heart beat becomes more 



