10 PROC. ENT. SOC. WASH., VOL. 21, NO. I, JAN., IQIQ 



In the Barbe system goods are washed in gasoline heated by 

 means of a steam jacket surrounding the washer, and it is re- 

 quired that the goods be dried for 70 minutes at a temperature 

 of 210 F. (98.8 C.) as registered on the upper gauge inserted 

 through the side of the machine insulated from the steam jacket. 

 The temperature requirements of this system are so high that 

 it is obviously efficient in destroying both lice and their eggs. 



Practical Dry Cleaning Experiments. 



Practical experiments under actual dry cleaning conditions were 

 made at a commercial establishment in Washington. 1 The com- 

 plete process was tested as follows: 



Experiment i. Complete process. 



The washer used was a standard dry cleaning rotary washer 

 measuring 32" X 50". About 15" of gasoline was let into the 

 machine. The fluid used was clarified gasoline at a temperature 

 of 65 F. (18 C.) and gave a hydrometer reading of 60 Baume. 

 A load of 45 pounds of goods was put in. About one-half pound 

 of standard dry cleaning soap and two ounces of ammonia were 

 used. 



With this load were placed two army O. D. wool shirts. One 

 of these contained in the right hand pocket a small piece of cloth 

 to which were attached 107 eggs, 1-3 days old; in the left hand 

 pocket, 102 eggs, 5-7 days old. The load was washed for thirty 

 minutes, then extracted for about three minutes in a basket 

 centrifugal wringer. This shirt with the rest of the load was then 

 rinsed in new gasoline for fifteen minutes, and again extracted. 

 Then followed drying in the tumbler. The temperature in the 

 tumbler as read at the exhaust rose minute by minute as follows : 

 56.0, 01.1, 63.0, 65.5, 06.6, 68.3, G9"7, 70.8, 71.1 C. 

 In other words the requisite minimum of 71 C. was reached in 

 about ten minutes. We did not follow the specifications of leav- 

 ing the goods in the tumbler for thirty minutes, but reduced the 

 time to fifteen minutes measured from the time that 71 C. was first 

 reached. After five minutes the temperature was 75.8; after ten 

 minutes, 79.7 ; after fifteen minutes, 83.3 C. The goods were then 

 removed from the tumbler, and the eggs were removed from the 

 shirt and returned to pill boxes and kept in an incubator at body 

 surface temperature, i. e., at about 28 to 30 C. Check lots of 

 untreated eggs were kept under the same incubator conditions. 

 The hatching record was as follows: 



1 The writers are indebted to Mr. Bert Carter of tin- Curmack Pry 

 Cleaning Company for providing all fucilitii s for these tests. 



