Meteorology of South Africa. 
171 
This shows the preponderance of persistency in the west wind, the 
NW. and NE. equally coming in second. 
The plates give in diagram form the various wind roses based on the 
foregoing table ; they show conclusively how the persistence of the west 
wind falls off during the winter months. 
The Annual Eoses are worthy of consideration. It will be remembered 
that 1878 was a very wet year over the west, bringing up the yearly total 
of rainfall to a great height. It will be noticed how the west arm shortens 
from 1876 to 1878, and it is very strange that in the annual returns the 
persistency of the west wind failed altogether during May in the years 
1877 and 1878 ; in the latter this failure extended to June and July. The 
year 1879 was a very dry one over the west, and it will be seen that the 
west arm of the rose stretches out to its maximum. 
There must be, therefore, some connection between the rainfall over 
the west and the persistency of the west wind at Port Elizabeth, decreasing 
it in severe winters over the west, and increasing it in dry, but what that 
relationship is remains for the future to demonstrate. 
This condition is brought out in the Monthly Totals Rose. Here the 
west wind prevails during the months which are dry over the west, and 
fails during months when it is wet, so there must be something more than 
accident in it. 
It is evident from the foregoing investigation that at all times of the 
year, unless seriously affected by disturbances of sufficient magnitude to 
override them, land and sea breezes are to be traced in the winds at Port 
Elizabeth, and no reason can be assigned for doubting such a condition 
elsewhere along the coast. That such exists over the Cape Peninsula is 
more than probable, but for the present this point has not received 
sufficient consideration, although it is hoped that before long the wdnds of 
this portion of South Africa may be investigated in a similar manner to 
what has herein been done for Port Elizabeth. 
