448 
Combating Lousiness 
(iii.-iv. 1918) that he has constructed two huts in France which, judging 
from his description and sketch plans, are an improvement on the fore¬ 
going Models A and B. Model C affords a better safeguard against 
conflagrations and doubtless distributes the heat more uniformly. Owing 
to the 6-inch interspace between the sheets of galvanized iron, forming 
the double walls and roof, being packed with clay, the structure is much 
better secured against loss of heat. 
A corrugated iron floor (15 x 20, or 8 x 11 ft. in the smaller hut), 
perforated with numerous holes, separates a cellar-like space (6 ft. high) 
from the heating chamber proper (7 ft. high) which lies above. The iron 
floor is supported on 4 iron rails resting on brick pillars situated in the 
cellar. The floor of the cellar is below ground level; a door opens into 
the cellar and steps lead down into a pit fronting it. By this arrangement 
the braziers (2, measuring 18 inches across) may be served and removed 
at will without entering the disinfestation chamber. The latter is pro¬ 
vided with bars suitably arranged (as in Fig. 9) for the reception of 
clothing or blankets. The air from the outside enters at floor level on 
either side of the cellar door and traverses two pipes ending beneath the 
braziers; the heated air traverses the perforations in the floor and escapes 
through two side ventilators in the walls of the hut after circulating in 
the space. The braziers are covered by hoods with flues leading to a 
chimney at the side whereby the excess of coke fumes escapes. The door 
to the chamber leads to a 4 ft. gangway between the two tiers of bars, 
the attendant treading upon a gang-plank resting on the iron floor. 
Experimenting with the smaller hut (floor area 8 x 11 ft.) Captain Orr writes 
that when the outside temperature was 10° C., on first putting in the burning 
braziers at 2.10 p.m., the empty chamber attained 60° C. in 30 minutes, rising to 
80° C. in 2J hours. When the doors were opened for 15 minutes, there was a fall 
to 46° C., but on shutting the door there was a rise to 67° C. in 20 minutes. By 
8.30 p.m. the walls had evidently grown warmer, for on opening the chamber to 
cool it and again closing the doors, 70° C. was attained in 8 minutes, although the 
coke braziers had not been replenished whilst burning since 10 a.m. The braziers 
were still burning next morning, but owing to the dying down of the fires, the 
temperature had by that time fallen to 35° C. at 7.30 a.m. The braziers were now 
removed, filled, and reintroduced at 9 a.m., 64° C. being attained in 14 minutes. 
During this second day the chamber was repeatedly opened, cooled, and closed, it 
being found that it readily heated up to 65° C. in 4-6 minutes. 
When the chamber was loaded with effects, it was found that it took 
twice as long to heat up as when it was empty. Starting at 38° C., after 
leaving the doors open for 15 minutes, 65° C. was attained 10-12 minutes 
after the doors were closed. The fumes from the coke caused no 
