DDT Formulations 79 



Kerosene is a good material for household inseaicides 

 because it doesn't evaporate too rapidly, and thus carries the 

 poisons where they will do the most good. In addition, 

 there is much less fire hazard with kerosene than there would 

 be with the much-more-volatile gasoline, although you must 

 keep kerosene away from open flames, as many people have 

 found out to their sorrow when they poured some kerosene 

 into the old wood stove, not noticing that there was still 

 some fire or hot coals present. 



The ordinary kerosene or No. 2 fuel oil that your 

 dealer can supply you with is perfealy all right for making 

 an insect spray, particularly for use in barns and chicken 

 coops, but its irritating odor is rather objectionable around 

 the house. For that reason, most household insecticides are 

 made with kerosene that has been treated to remove the 

 odoriferous constituents. Incidentally, deodorizing is ap- 

 parently an expensive process; at least the deodorized product 

 costs about three times as much as the produa you burn in 

 your lantern. To top it all off, manufacturers, to cover up 

 the odors of their insecticides, add small amounts of per- 

 fumes to "make it stink pretty." 



Why DDT in Space Sprays? 



In spite of the faa that pyrethrum and the thiocyanates 

 are rather good insect killers, they can't compare with DDT. 

 A Viofo solution of DDT will kill a higher percentage of 

 insects than will much higher quantities of these other kill- 

 ers, and at a much lower cost. But DDT, in spite of its 

 marvelous killing powers, is slow acting: it does not have the 

 desirable high knockdown characteristics of the other in- 

 secticides. Therefore, a kerosene solution of DDT alone 



