STORMS. 
259 
tions have been discussed for a single month, whereas, with regard 
to others, not a single record is to be found in any of the numer- 
ous log-books at the National Observatory. 
559. Typhoons. — The China Seas are celebrated for their furi- 
ous gales of wind, known among seamen as typhoons and white 
squalls. These seas are included on the plate (VIII.) as within 
the region of the monsoons of the Indian Ocean. But the mon- 
soons of the China Seas are not five-month monsoons 475) ; 
they do not prevail from the west of south for more than two or 
three months. 
560. Plate V. exhibits the monsoons very clearly in a part of this 
sea. In the square between 15° and 20° north, 110° and 115° 
east, there appears to be a system of three monsoons ; that is, from 
northeast in October, November, December, and January ; from 
east in March and April, changing in May ; from the southward in 
June, July, and August, and changing in September. The great 
disturber of the atmospheric equilibrium is situated among the arid 
plains of Asia ; their influence extends to the China Seas, and 
about the changes of the monsoons these awful gales are experi- 
enced. 
561. In like manner, the Mauritius hurricanes, or the cyclones 
of the Indian Ocean, occur during the unsettled state of the at- 
mospheric equilibrium which takes place at that debatable period 
during the contest between the trade-wind force and the monsoon 
force 477), and which debatable period occurs at the changing 
of the monsoon, and before either force has completely gained or 
lost the ascendency. At this period of the year, the winds, break- 
ing loose from their controlling forces, seem to rage with a fury 
that would break up the very fountains of the deep. 
562. So, too, with the West India hurricanes of the Atlantic. 
These winds are most apt to occur during the months of August 
and September. There is, therefore, this remarkable difference 
between these gales and those of the East Indies : the latter occur 
about the changing of the monsoons, the former during their height. 
In August and September, the southwest monsoons of Africa 
479) and the southeast monsoons of the West Indies 474) are 
at their height ; the agent of one drawing the northeast trade- 
winds from the Atlantic into the interior of New Mexico and Tex- 
as, the agent of the other drawing them into the interior of Africa. 
