238 WITH SCOTT: THE SILVER LINING 



the wind, and another (not shown) pointed away from wind, and was 

 worked by its suction effect. The outer tube is sketched in Fig. C, 

 and the lower end of this long pipe communicated with the blizzometer 

 inside the hut. A practical experience with the blizzometer in a 

 blizzard is given in another paragraph (p. 222). Since the resulting 

 pressure varies as the square of the velocity, it is necessary to arrange 

 the inner capacity of the drum to suit. It has, therefore, a paraboloid 

 vertical section (being wider lower down), so that the heaviest gusts 

 do not raise the piston (and pen) disproportionately high on the graph. 

 The essential details of the apparatus are shown in Fig. D, the instru- 

 ment being about a yard long. In Fig. E is shown the ingenious 

 method for obtaining a continuous record of wind direction. The 

 wind vane on the roof as it swings twists a cylinder on the same axis. 

 This cylinder was situated in the porch in close proximity to the 

 acetylene plant, over which we had to climb to regulate the 

 instrument. On this cylinder was wound a sheet of metallic paper. 

 At the side was a sliding point which made a mark when pressed 

 on this paper. It was actuated by a clockwork which gradually 

 lowered the point to the bottom during a period of seven days. 

 With a steady wind a vertical ribbon was marked on the chart, and 

 in our case nearly all the marks were confined to the south-east or 

 north quadrants. 



Simpson next proceeded to explain the instruments for detecting 

 the electrical condition of the air. This was merely a variant of the 

 quadrant electrometer, which is rather too technical an instrument for 

 the layman. The magnetic measurements are also open to the same 

 objection. The Dine's Meteorograph is, however, a very ingenious 

 instrument, and I have given an account of it in a preceding section 



(P- 2 34). 



There was a crowded and enthusiastic audience, and the 

 experiments were most striking in view of Simpson's limited 

 material. As a preliminary Ponting nearly blew us up with 

 his acetylene lantern, and canny Dr. Bill sought shelter under 

 the table ! 



In the second football match, I tried the effect of wearing 

 light American shoes in place of heavy ski-boots. I don't 

 think it improved my speed much, though I managed to give 

 Crean two " busters," which pleased me greatly. Simpson 

 did not appear, and later we found that Wright had seen the 

 door of the magnetic hut unfastened, and had locked it while 

 Simpson was within ! My tight thin shoes naturally made 

 my toes "go," but by diligent rubbing and gradual warming 

 before I entered the hut I managed to bring them back 

 without any great pain. 



