THE ENTOMOLOGIST’S 
WEEKLY INTELLIGENCER. 
No. 240.] SATURDAY, MAY 11. 1861. [Pbice Id. 
EAST WINDS. 
At this season of the year we are all 
apt to have our tempers tried by the 
j prevalence of the east winds. It is a 
I law of Nature that the east winds 
. should blow just now, and that it 
j should blow for about six weeks be- 
j tween the beginning of March and 
j end of May; the same law requires 
1 that these winds should be cold and 
j very dry. The east winds in May are 
j felt as more uncomfortable and more 
I unendurable than any weather we ex- 
I perience at any other portion of the 
year. 
Captain Maury, in his work on the 
‘Physical Geography of the Sea,’ has 
I a theory on the circulation of the atmo- 
sphere which is extremely interesting. 
I Starting with the intertropical trade- 
winds, which blow both from the north- 
east and south-east to the equator, he 
assumes that at the region of equatorial 
calms, where these winds meet, they 
vise up, intercross, and the wind from 
the south proceeds northwards, that 
from the north proceeds southwards ; 
but as, owing to the difference of 
velocity of the earth’s atmosphere in 
different parallels of latitude, winds 
from the equator to the poles take an 
easterly direction, and those from the 
poles to the equator pursue a westerly 
course. Thus the south-east trade-wind 
rising up and crossing the equator 
becomes an upper current from the 
south-west, and thus flows onward on 
the top of the north-east trade-winds 
till it reaches the tropic of Cancer, 
where, according to Captain Maury’s 
theory, its progress is arrested by an 
opposing upper current from the north- 
east. Here there is a belt of variable 
winds and calms, in which, as. at the 
equator, the winds intercross and the 
upper currents descend to the surface: 
accordingly the south-west wind, which 
had been the upper current from the 
equator' to the tropic of Cancer, now 
becomes the lower current, and is our 
prevailing warm and moist south-west 
wind; warm because it comes to us 
from the equator; moist because it has 
blown over the surface of the sea from 
the tropic of Capricorn to the equator, 
and again since it descended from the 
upper regions in 30° north latitude. 
This wind continues its course steadily 
G 
