Behavior of the Atlantic : 47 



the trade winds move some degrees of latitude north or south with 

 the seasons it follows that even the doldrums also shift a little. 



The Northern limit of the doldrums is the southern limit of the 

 northeast trade winds. This limit shifts and is never precisely defined, 

 but in September, at the time of the equinox, it will be found at about 

 10° north latitude in mid-Atlantic. The trades there form a broad 

 band which extends northward to about 30° north. However, in the 

 eastern Atlantic the northern limit swings up to include all of the 

 African coast and also part of the Spanish coast, terminating near 

 Cape Trafalgar. On the west it is described as ending at Cape Canav- 

 eral, a midpoint in the east coast of Florida. 



Within this broad band the prevailing wind comes from the north- 

 east and may blow from this quarter steadily with good force (aver- 

 age force four on the Beaufort scale) day after day. This is of course 

 a general statement based on averages of figures reported by many 

 ships over many years. In practice the wind might blow anywhere 

 between north and east, but it could be expected to blow from this 

 quadrant about 80 per cent of the time. Three or four per cent of the 

 time even in the center of the belt there will be calms, light airs or 

 variable winds. The rest of the time brisk winds of short duration 

 might be expected from any quarter of the compass. This is so high 

 an average of favorable winds as to insure a relatively quick passage 

 to any ship bound from European ports to southern ports of the 

 American Atlantic coast or to Gulf ports or to the Caribbean. Many 

 captains of sailing ships bound from European ports to Norfolk, Bal- 

 timore or even New York have found it just as fast and far more 

 comfortable to take their vessels "south about" through the trades 

 than to buck the winter westerlies on a more direct course. 



Life in the trades is usually drawn and described as fair and com- 

 fortable. It can be so but it can also be boisterous and rough. Storms 

 are not excluded from the trades area and I know from personal expe- 

 rience that when meteorological conditions give them an extra push 

 they can create hard work and discomfort for a small ship. 



It is important to observe that the trades though called northeast 

 vary their direction according to a regular plan. All along the west 

 coast of Africa as far as Cape Verde winds come from the north even 

 more frequently than from the northeast. Between Cape Verde and 

 the West Indies they come from the east more frequently than from 

 the northeast. As they approach the American coast north of the 

 Windward Islands and about the Bahamas they blow from the east 

 and southeast as much as from the northeast. 



