56 LICE AND THEIR MENACE TO MAN 



or brick, there being a space of two inches be- 

 tween the lining and the outer wall in order to 

 conserve the heat. By the side of the chamber 

 is a vertical boiler which supplies the steam. 

 The whole structure is built on a concrete floor. 

 From the boiler runs a system of radiator pipes, 



OlotWs 



-T f T 1- 



FIG. 11. IMPROVISED DISINFESTOR. 



An ordinary galvanised iron sanitary bin. (After Hunter.) 

 a, escaping steam ; b, wire grid. 



which pass along the sides and roof of the chamber, 

 and a second series run along the floor. From the 

 latter system live steam is allowed to enter by 

 a number of jets. The water condensed flows 

 away by means of a drain in the concrete base. 

 There is a wooden grid raised a little above the 

 floor to allow the operators to move about in 



