CHAPTER XI 
TO MIDWINTER DAY 
Thursday, June I. — The wind blew hard all night, 
gusts arising to 72 m.p.h. ; the anemometer choked five 
times — temperature + 9 0 . It is still blowing this morn- 
ing. Incidentally we have found that these heavy winds 
react very conveniently on our ventilating system. A fire 
is always a good ventilator, ensuring the circulation of 
inside air and the indraught of fresh air ; its defect as a 
ventilator lies in the low level at which it extracts inside 
air. Our ventilating system utilises the normal fire 
draught, but also by suitable holes in the funnelling 
causes the same draught to extract foul air at higher 
levels. I think this is the first time such a system has 
been used. It is a bold step to make holes in the funnelling 
as obviously any uncertainty of draught might fill the 
hut with smoke. Since this does not happen with us it 
follows that there is always strong suction through our 
stovepipes, and this is achieved by their exceptionally 
large dimensions and by the length of the outer 
chimney pipe. 
With wind this draught is greatly increased and with 
high winds the draught would be too great for the stoves 
if it were not for the relief of the ventilating holes. 
