DISINFESTATION 57 



comfort when they load and unload. The 

 material treated is hung loosely on a number of 

 pegs, the garments being turned inside out. In 

 the routine working this chamber is kept con- 

 stantly hot by means of the radiator pipes. 

 When the operation commences the doors are 

 closed and steam under pressure is allowed to 

 enter through the jets in the floor system of pipes, 

 and the lethal temperature for the lice is quickly 

 attained in all parts of the chamber, the time 

 necessary for this varying with such factors as 

 the size of the chamber, the quality and amount 

 of the load, the size of the boiler, and the steam 

 pressure. This heat is maintained for as long as 

 is necessary, the higher the temperature attained 

 the shorter the period required. A check is kept 

 on this by means of a maximum thermometer, 

 which is wrapped in several thicknesses of blanket 

 and placed in that position which experience 

 shows is the coolest. For the exact working of 

 the machine so as to avoid the waste of fuel 

 caused by supplying more heat than is necessary, 

 a knowledge of the particular type in use must 

 be gained by a series of experiments. At the 

 end of the operation the steam is shut off at the 

 jets, the door is slightly opened, as is also the 

 outlet of the drainage system in the floor, and 

 the dry heat supplied by the radiator system 

 is allowed to act for a few minutes to partially 

 dry the contents. 



Although disinfestation by wet heat must, for 



