380 
Transactions of the Royal Society of South Africa. 
DIVISION (1). 
Section (a). — Here we have only 3 cases, 1 being followed by rain and 
the other 2 by dry weather; the former was a fall of 0-13 in. following a 
deep summer type depression, where no rain would have been expected. 
Section (b). — There are 10 cases, 2 being followed by rain ; on 1 of 
these only 0*02 in. fell, and the other was due to a winter type depression. 
Section (c). — This happened upon 83 occasions, and only upon 3 did 
rain follow. 
Prediction for Division. — Dry weather. 
DIVISION (2). 
Section (a). — Here we have 2 cases, followed by dry weather. 
Section (b). — Here are 14 cases, and rain followed upon 5 of them. 
The rainfall on each of these 5 occasions was entirely due to a recently 
passed winter type depression. 
Section (c). — This condition came upon 86 occasions, and on 78 of 
them dry weather followed ; on 4 of the wet days less than 0*05 in. fell, so 
we have only 4 actual failures. 
Prediction for Division. — When pressure is mean at L'Agulhas 
and a winter type depression has just passed, look out for rain, both 
at the Eoyal Observatory and at L'Agulhas ; in all other cases pre- 
pare for dry weather. 
DIVISION (3). 
Section (a). — 1 case followed by rain. 
Section (b). — 1 case followed by rain. 
Section (c). — Out of 22 cases, 12 were followed by rain and 10 by dry 
weather ; this is an unnatural condition, blending winter with summer 
types, the rapid rise at L'Agulhas being the summer type and the high 
barometer at Clanwilliam the winter one. 
Prediction for Division. — When a winter type depression is 
passing off and the glass is low at L'Agulhas, rain can be expected ; 
otherwise prepare for dry weather. 
SUB-GEOUP (B). 
This can be brought about by a wedge of high pressure pushing up 
from the south of L'Agulhas, reaching to Clanwilliam. Or, again, a 
recovery of pressure at the rear of a depression may be interfered with by 
a secondary to the west or north-west of the Eoyal Observatory. 
