8 



BULLETIN 1228, U. S. DEPARTMENT OF AGRICULTURE. 



Paradichlorobenzene dissolved in kerosene and gasoline, and 

 naphthalene dissolved in kerosene, gave no better results than the 

 respective oils by themselves. Naphthalene dissolved in gasoline 

 was more efficient than gasoline itself. The use of paradichloro- 

 benzene is not advisable, as it was found to impart a taste to eggs 

 laid after the treatment of the chicken house. 



Mechanically mixed in whitewash and applied immediately, wood 

 creosote oil was efficient when the oil comprised 11 per cent of the 

 spray. Crude carbolic acid in whitewash was efficient at 10 per cent 

 and inefficient at 8 per cent. Phenol was moderately efficient in 

 whitewash at 11 per cent. 



The other tests reported in Table 2 were with mixed oils. They 

 demonstrated the efficiency of heavy tar oils. The coal-tar oil 

 (carbolineum) used in tests 13 to 18, inclusive, had a specific gravity 

 of almost 1.2. Such an oil evaporates much more slowly than a 

 mineral oil of the type of kerosene. 



Oils were used in the form of emulsions also. These are divisible 

 into three types — emulsions of light mineral oil, heavy mineral oil, 

 and coal-tar oils. In some of the second class a small quantity of 

 coal-tar oil had been added. 



Table 3 presents the tests made with oil emulsions against the 

 chicken mite. 



Table 3.— Results of tests with oil emulsions against the chicken mite. 





Nature of oil. 



Composition of emulsion. 



Dilution. 





Test 

 No. 



Oil. 



Soap. 



Phe- 

 nols. 



Water. 



Un- 

 deter- 

 mined, 

 by dif- 

 ference. 



Eesult. 



1 



2 



Light mineral 



do 



Per ct. 

 77.0 

 77.0 

 .82.2 

 82.2 

 82.2 

 84.1 

 84.1 

 79.6 

 82.7 

 82.6 

 82.6 

 30.4 

 41.0 

 41.0 

 48.0 

 50.0 

 63.9 

 63.9 

 2 3.2 



Per ct. 



4.0 



4.0 



8.0 



8.0 



8.0 



7.5 



7.5 



5.9 



5.0 



4.2 



4.2 



24.6 



22.0 



22.0 



25.6 



22.0 



21.9 



21.9 



1.0 



Per ct. 



6.9 



5.9 



40.0 

 30.0 

 30.0 

 12.0 

 16.0 

 7.5 

 7.5 

 ( 2 ) 



Per ct. 

 18.6 

 18.6 

 6.9 

 6.9 

 6.9 

 7.3 

 7.3 

 7.6 

 6.4 

 13.2 

 13.2 

 5.0 

 5.0 

 5.0 

 14.4 

 8.0 

 6.7 

 6.7 



Per ct. 

 0.4 

 .4 

 2.9 

 2.9 

 2.9 

 1.1 

 1.1 



2.0 



2.0 



4.0 

 3 95.8 



lto3 



lto7 



1 to 2.5 



lto4 



lto6 



ltol6 



lto24 



lto4 



lto9 



lto3 



lto4 



1 to 157 



1 to 32 



lto99 



lto49 



1 to 24 



1 to 12.3 

 ltol9 



2 pounds to 

 1 gallon. 



Efficient. 



3 



4 



Heavy mineral. . . 

 do 



Efficient. 

 Moderately efficient. 



5 



....do 



6 



...do 



Do. 



7 



do 



Do. 



8 



...do 





9 



....do 





10 



do 



Efficient. 



11 



..do 



Do. 



12 







13 



do 





14 



do 





i 15 



do 



Moderately efficient. 

 Efficient. 



1 16 



do 



17 



do..'. 



Moderately efficient. 

 Do. 



18 



do 



19 



do 











i Box tests. 



2 Coal-tar oils and phenols 3.2 per cent. 



3 Sand and mineral pigment 95.8 per cent. 



The oil used in tests 1 and 2 was kerosene. The emulsion was effi- 

 cient when diluted 1 to 3 parts water. 



In tests 3 to 11 the material contained a heavy mineral oil with 

 high boiling point, and in addition a small amount of coal-tar oil was 

 present in that used in tests 6 to 9, inclusive. 



These oils were efficient when used at dilutions of 1 to 2.5 and lto 

 3 parts water. 



