206 Proceedings of the Poyal Society of Edinburgh. [Sess. 
Table I. — Showing the Departures from the Normal of Barometric Pressure, 
Temperature, and Wind Velocity at M‘Murdo Sound (1) and Laurie Island, 
South Orkneys (2). Wind Velocity on Beaufort Scale is given for Evan- 
gelists’ Island (3). 
Pressure. 
mm. 
Temperature 
in Degrees 
Centigrade. 
Wind Velocity, Metres 
per Second. 
Summer: Dec., 
Jan., Feb. 
(0 
(2) 
(1) 
(2) 
(1) 
(2) 
(3) 
1902-03 
+ 1-7 
-1*2 
-0*5 
-0*8 
-2*0 
4-0*2 
-1*1 
1903-04 
-3*4 
-2*2 
4-lT 
4-0-5 
- 1*9 
4-0*5 
-0*1 
1910-11* . 
-3-9 
4-0*5 
4-0*6 
-0*1 
-b2*4 
-0*6 
+ 0*1 
1911-12 
4-5*5 
4-3*1 
-1*3 
4-0*4 
4-1*4 
-0*2 
-80*9 
Autumn : Mar., 
April, May. 
1902 . 
4-2*2 
-1*1 
4-0*8 
4-1*2 
-1*4 
4-1*7 
-0*8 
1903 . 
4-1*0 
-1*0 
-3*3 
-0*7 
-2*6 
4-1*8 
-0*6 
1911 . 
-0*9 
4-6*4 
4-2*1 
4-0*5 
+ 0-8 
-1*7 
-80*9 
1912 . 
-2*4 
-4*2 
4-0*5 
- 1*0 
-h3*3 
-1*6 
-80*5 
Winter : June, 
July, Aug. 
1902 . 
4-1*2 
-2*1 
4-0*3 
-2*8 
-2*3 
4-2*6 
-1*1 
1903 . 
-F3*9 
-0*5 
-1*7 
4-0*4 
-2*8 
4-0*3 
-0*5 
1911 . 
-1*0 
4-lT 
-2*5 
4-3*3 
-0*2 
- 1*4 
4-1*2 
1912 . 
-4*0 
4-1-6 
4-4*0 
- 1*1 
-F5*4 
- 1*5 
4-0*2 
Spring : Sept., 
Oct., Nov. 
1902 . 
4-4*0 
-1*3 
-0*9 
-1*6 
-2*1 
4-1*6 
-1*2 
1903 . 
-5*4 
4-1*2 
-1*1 
4-0*2 
- 1*2 
-0*3 
-0*1 
1911 . 
-0*1 
4-2*2 
-0*5 
4-1*1 
4-1*0 
-0*6 
4-0*1 
1912 . 
4-1*4 
-1*9 
4-2*5 
4-0*3 
4-2*5 
-0*5 
4-1*3 
A study of these numbers seems to establish the existence of a pro- 
nounced see-saw in the case of barometric pressure and wind velocity at 
all seasons of the year. In the sixteen seasons discussed there are only 
three instances in which as regards barometric pressure the deviation from 
the normal is characterised in the two cases by the same sign, viz. the 
summers of 1903-04 and 1911-12, and the autumn of 1912. Again, only 
in the winter of 1911 and the spring of 1903 is the sign of the departures 
of the wind velocity from the normal the same at these two widely 
separated stations. As regards temperature the results, except for the 
winter period, are indefinite ; during this season, however, the contrast 
between the two regions is strongly marked. The comparative failure 
in the pressure see-saw in summer is doubtless due to the relatively feeble 
Antarctic circulation then prevailing, there being at this time a levelling-up 
* For pressure and wind velocity the values refer only to the months of January and 
February 1911. For temperature, December 1910 at Cape Evans has been interpolated. 
