Gr. H. F. Nuttall 
441 
Hot-air huts. A plan I have advocated and which I am glad to say 
has been to some extent adopted, is the use of huts, or possibly double- 
walled tents for the destruction of lice by hot air. This method, which 
I suggested to Captain Orr in 1915, is suitable for base camps and offers 
many advantages in that large quantities of clothing, blankets, etc., can 
be conveniently handled at a time. The air , heated to 60-70° C. (higher 
temperatures not being required) is made to circidate in the space, either 
naturally through inlets and outlets or it is kept moving by fans. The 
objects are hung on racks or wires (Orr) or by means of hooks attached 
to these, sufficient space being left between the articles to allow for the free 
circulation of air about and between them. The huts vary in size according 
to requirements and they may be heated either by stoves, steam pipes, 
or, as Captain Orr found, by coke braziers in the manner presently to be 
described. Such structures are preferably built low and it is essential 
that they should be secured against loss of heat by possessing double 
walls enclosing an intervening air-space. 
Captain Harold Orr, C.A.M.C., at Shorncliffe, having proved the 
efficiency of a makeshift hot-air hut built of corrugated iron, after¬ 
wards devised a very useful type of hut which was further modified in 
points of detail by Captain J. T. Grant, R.A.M.C. These huts are shown 
in the illustrations and descriptions that follow (Grant and Peacock’s MS. 
Report, W.O. i. 7918). The erection of the huts is such a simple matter 
that; even for army use, it is unnecessary to consider the making of 
sectional structures of the kind. 
Improvised hot-air hut ( Model A, Figs. 5-7, Grant and Peacock, MS. 
Report, W.O.). A simple wooden framework, of the dimensions indicated 
in the figures, is erected with 3x2 inch timber and covered on both the 
inside and outside with canvas (Fig. 6), thereby forming a double-walled 
canvas chamber (Fig. 7) which is afterwards roofed with corrugated iron. 
An air-space 3 inches wide separates the two canvas walls. The chamber 
has two entrances, each closed by canvas roll curtains that are weighted 
below and fastened at the sides to the hut. As the hut here figured was 
erected in an exposed position, it was found necessary to anchor it by 
guy ropes after the manner of a tent. Two tiers of heavy wires running 
parallel to each other traverse the hut beneath the ceiling, the one tier 
running at right angles to the other. The wires serve for suspending 
blankets (Fig. 7) or clothing attached to hooks, hung on the wires. 
A horizontal sheet of iron, ca. 5x5 feet, suspended at the corners by 
four wires hanging from the roof, deflects the hot air rising from the 
glowing braziers beneath; it serves as a heat radiator and guard against 
