tS2 



OBSEEVATIONS ON THE WINDS. 



West African S.W. Monsoon. This wedge-shaped area, whose apex 

 reaches in July to 40° or 45° "W., extends on the African coast at that period 

 from 5° N. to 16° or 17° N. To the West of this there is still a belt of 

 almost constant rain "under the Equatorial cloud ring," called the Equa- 

 torial Calms, which, however, is much narrower, and perhaps at times 

 may not be encountered. The Trade Wind is at its Southerly limit in 

 March and April, reaching in mid-ocean sometimes to 3° S., but seldom so 

 far as 3° N. on the East side. It remains there for two or three months, 

 and then advances Northward till August and September, when it is 

 seldom found South of the parallel of 9° N. ; indeed, this parallel may be 

 taken as the mean Southern hmit of the N.E. Trade. This Northern 

 division of the Trade Winds is owing to the unequal distribution of land 

 in the two Hemispheres. * 



The following useful Table was drawn up by the late Captain Horsburgh, 

 as the limits usually found in the track generally pursued by the East 

 Indiamen, at the commencement of the nineteenth century : — 



TABLE, showing the Equinoctial Limits of the N.E. and S.E. Trade Winds, 

 between the Meridians of 18 and 26 degrees West. 



(55.). An inspection of the Weather Charts wiU show that at times the 

 two Trade Winds are separated by only a very narrow belt of Calms, and 

 vessels have even passed from one to the other without being becalmed 

 for an hour. Thus, as before stated, it is impossible to state certainly 

 where the Trade Winds will be met with or lost at various seasons. All 

 that the charts and diagrams can do is to show their probable limits. 



(56.) The Direction of the N.E. Trade Wind is an important nautical 

 consideration. Its mean direction in the circuit of the earth is estimated 

 at N. 47° E., but it varies considerably under the influence of the land, 

 and especially so in the North Atlantic. As mentioned above, the Trade 

 Wind blows much more from the Northward to the Eastward of long. 25° 

 —that is, within 400 or 500 miles of the African coast, — than it does in. 



