1914-15.] Meteorological See-Saw over Antarctic Seas. 
215 
Station. 
Lat. S. 
Long. 
1902. 
1903. 
1908. 
1911. 
1912. 
Mean. 
M‘Murdo Sound . 
77° 44 
163° 34'e. 
0 
-P6 
-1°'8 
+ 3°-0 
-P2 
o 
+ 1-8 
- 1°7-8 
Hobart 
42 53 
147 20 E. 
+ 0*1 
+ 1*6 
-0-1 
+ 0-1 
-0-6 
12-5 
Adelaide 
34 56 
138 35 E. 
-t-0‘9 
+ 0-4 
-0-7 
-1-0-3 
-1-0 
17-2 
Punta Arenas 
53 10 
70 54 W. 
+ 0*4 
+ 0-4 
-1-5 
+ 0-7 
-0*1 
6*0 
Kio de Janeiro 
22 55 
43 10 W. 
-1-0-3 
+ 0A 
-0-1 
+ 0-2 
-0-8 
22-1 
Owing to the shortness of the period available one cannot utilise the 
MMurdo Sound seasonal data as an index of what will occur later in 
other localities. The contrast between the temperature conditions there 
in summer and those which hold in autumn at Adelaide, Perth, Curityba, 
Rio de Janeiro, and St Helena is, however, so remarkable as to be worth 
drawing attention to. 
Station. 
Lat. 
Long. 
1903. 
1904. 
1909. 
1911. 
1912. 
Mean. 
Summer. 
M‘Murdo Sound . 
77° 44 
166° 34 E. 
O 
- 1-0 
+ 0°-6 
+ 2°0 
+ 0°1 
- 1-8 
o 
-5-6 
Autumn. 
Adelaide 
34 56 
138 35 E. 
-f-0'7 
-0-4 
-0-2 
-0-4 
+ 0-4 
17-5 
Perth .... 
31 57 
115 45 E. 
+ 1-1 
- 1-1 
-0-5 
-0-5 
-f-0’8 
18-7 
Curityba 
25 26 
49 16 W. 
+ 0-9 
0-0 
-0-6 
-0-8 
+ 0-7 
16-8 
Rio de Janeiro . 
22 55 
43 low. 
+ 0-2 
-0-3 
-0-1 
-0-3 
+ 0-4 
23’3 
St Helena . 
15 57 
5 40 W. 
+ 0*7 
-0-1 
-0-8 
-0-1 
+ 0-4 
18-3 
Thus cool summers at M‘Murdo Sound were followed by warm autumns 
at Adelaide and Perth, and also in the south of Brazil and in the south- 
east trade-wind region of the South Atlantic, while mild summers at 
M‘Murdo Sound were followed by cool autumns in the regions specified. 
The connection between MMurdo Sound and the region of the south-east 
trades of the South Atlantic may not at first sight appear very obvious. We 
have, however, seen that a see-saw exists between the Weddell and the 
Ross Seas, more especially as regards barometric pressure and wind force. 
A further connection is found between the wind force at the South Orkneys 
and the mean temperature at St Helena. For Laurie Island we have wind 
data based on hourly observations since June 1903.^ Dealing only with 
the complete annual values since 1904, and bloxaming these in continuous 
three-year groups, we find that there has been a progressive diminution in 
the wind velocity from the first three-year group, 1904-06, down to the 
* Davis, Anales de la Oficina Meteorologica Argentina, Tomo xvii ; Glima de las Isles 
Orcadas del Sud, Secimda Parte, p. 137, Buenos Aires, 1913. Data from 1911-14 kindly 
sent by Dr Davis in manuscript. 
