DDT Formulations 69 



containing up to 50% DDT and the rest inert ingredients, 

 used as dispersions in water for the same purposes as DDT 

 emulsions. (6) Agricultural dusts, containing usually 

 from 1 to 5 % DDT, for direct application to field crops for 

 the control of various insect pests. (7) Paints, usually 

 with about 5 or 6% DDT incorporated in a synthetic-resin 

 binder, principally for interior purposes where residual insea- 

 killing powder is desired. 



Sprays and Sprays 



When the housewife goes into a store and asks for some 

 DDT, the clerk hands her a bottle of stuff with the letters 

 DDT in large type. The DDT content may he 5% or less, 

 so the good woman should stop a moment and think be- 

 fore saying those words that every clerk likes to hear: "I'll 

 take it. How much is it?" If she wants something that 

 she can apply to the walls of the dining room so that the flies 

 that light there over the next six months will die, she had 

 better make sure that it says 5 % in front of the letters DDT. 

 But if she merely wants to kill the flies that happen to be 

 around at the moment she sprays, she will find that a con- 

 siderably lower concentration of DDT will do the trick. 



You see, fly sprays are of two types: space sprays and 

 residual sprays. Space sprays have been in use for many 

 years, and those exciting words, "Quick, Henry, the Flit," 

 have been heard from one end of the land to the other — 

 much to the profit of the manuf aaurer. When using a space 

 spray you merely aim your gun in the general direaion of the 

 insects and hope that some of the misty particles hit each pest. 

 Any insect who escapes the spray is safe, at least until the 

 next time you let go with your ammunition. The older space 



