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 11 5° 

 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. 



