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METEOEOLOGY OF SOUTH AFEICA. AN INVESTIGATION 
INTO THE LAND AND SEA BEEEZES CONDITIONS AT 
POET ELIZABETH. 
By a. G. Howard, M.S.A. 
(CommuDicated by L. Peringuey, F.E.S.S.Afr.) 
(Eead Oct. 19, 1910.) 
(Plate IV.) 
The object of this paper is prehminary, as it is merely the outcome of 
an investigation of the 8 a.m. and 8 p.m. directions of wind at Port Eliza- 
beth during the four years 1876 to 1879 inclusive. The facts it proves 
being merely deduced from two observations per day may or may not be 
borne out when an investigation is made having data from self-recording 
instruments, but enough has been elucidated to show that the results of 
the four years tabulations go to prove that all winds at Port Elizabeth 
were more or less governed by a diurnal influence analogous to land and 
sea breezes. 
That land and sea breezes are experienced along all coasts in the 
world is admitted; the reasons why they should exist have also been 
established, so nothing need be stated here in this connection other than 
the effect of these conditions in South Africa. 
Sometimes disturbances break into the sequences of these breezes, but 
an investigation of wind directions at morning and evening, extending 
over long periods, can always bring their existence to light. 
Sometimes they are masked to a certain extent by prevailing winds, 
which is often the case with South Africa, but even here a careful analysis 
will disclose their presence. 
Port Elizabeth has been chosen as a station for investigation as it is 
one on the high-pressure "col" between two permanent high-pressure 
areas, and its prevailing winds are west and east ; the observer there has 
always been reliable, and his observations are continuous, and were made 
at 8 a.m. and 8 p.m. 
It is well known that as the earth revolves the sun progresses vertically 
from east to west, and that a heat wave follows, having diurnal maxima 
and minima. But there is this difference, namely, whereas the atmo- 
sphere over the sea follows the movement of the sun and arrives at its 
maximum at or soon after the solar noon, that over the land attains to its 
