358 OBSERVATIONS ON THE CURRENTS. 



The Northern coast of Porto Bico is subjected to a Ground Sea, of scarcely 

 less force, and which has had the same effect on its coast as that of the 

 Virgin Isles. The old " English Pilot " observes, that the sea along the 

 North coast of Porto Rico " beats sometimes very ragingly." The force of 

 the waves that batter against the cliffs on which the Morro stands is 

 amazing; and any obseiver will admit that the spray is sometimes carried 

 more than 100 feet high. It has been said that, several years ago, a brig, 

 in consequence of carelessness, here became unmanageable, and was soon 

 dashed to pieces against the cliffs, but few of the crew escaping. 



(327.) Caribbean Sea. — Within or Westward of the Windward Island» 

 there is a prevailing Westerly drift, weak and uncertain in the Eastern 

 part of the sea, but gradually increasing in strength to the Westward. 

 This drift, passing from the Atlantic through the Caribbean Sea into the 

 Gulf of Mexico to feed the Gulf Stream, is not nearly so constant nor so 

 strong as might be argued, a priori, from the apparent magnitude of that 

 mighty current. Not only is it inconstant even in the mid-channel, but it 

 is diverted by local causes and land configurations into opposite direction^ 

 as hereafter is shown to be the case along the Colombian coast and in tha 

 great Bays of Guatemala and Honduras. It appears to combine with the 

 Tides in some degree, especially about the coasts of Cuba, Jamaica, and 

 Hayti. 



Upon referring to the description of the Guinea or Equatorial Counter- 

 Current, as recited in pages 325 to 334, it is shown that it extends much 

 farther to the Westward, during the period when the sun is in Northern 

 signs. The Western extension of the Guinea Current, coincident with the 

 increase of the Belt of Equatorial Calms (75), page 152, and f83), page 

 158, may owe its origin to the same causes, hitherto almost unexplained, 

 as those to which this uncertainty of the Westerly Drift across the Carib- 

 bean Sea is owing. 



Whether it is owing to the influence of the moon and the Tide, the effect 

 of barometric variations and distant and local Winds, or of Temperature 

 and the changes of the seasons, or of some hitherto unexplained eftect ol 

 the earth's rotation, has yet to be argued. It is probable that hereafter a 

 systematic examination of these apparently contradictory phenomena will 

 lead to some important conclusions in the general subject of Meteorology. 



(328.) Mr. R. Strachan, from his investigations, found the average daily 

 Westerly drift in this sea to be about 20 miles. In the Spanish Derrotero 

 de las Antillas it is stated that in crossing from the Southern coast, or 

 from Cartagena, to the Northern islands, it has been discovered that from 

 La Guayra to the Eastern ptvrt of Hayti, on a voyage made in December, 

 a difference of 106 miles to the Westward was found during the seven days 

 the voyage lasted. 



(329.) Lieutenant G. C. Hanus, of the U.S.S. Enterprise, states that in 

 November, 1890, when in the fairway of the Caribbean Sea, between lat. 

 14° 40' N., long. 75° 28' W., and lat. 13° 32' N., long. 77° 4' W., the 

 current was found to run about 1^ knot per hour, setting about W.N.W. ; 

 but, from this latter position the Westerly set was rapidly lost, and the 

 next day a slight Easterly current was found, which gradually increased 

 as the coast was approached near Colon. 



