THE GULF STREAM. 251 
or ‘the Mona Passage, until they reach the belt of variable and 
westerly winds, when they steer toward the European shores 
again. 
After reaching the Mexican coast, Columbus, by one of his 
broad generalizations, practically discovered the Straits of Flo- 
rida ; arguing that it must have an outlet into the Atlantic, and 
that he would thus escape the tedious voyage in the teeth of 
the northeast trades, which would be his lot if he attempted to 
find his way home by the usual route of the Windward or the 
Mona Passage. In 1519, an expedition inspired by Alaminos 
was despatched by Garay, Governor of Jamaica, to follow the 
easterly current running along the northern shores of Cuba. 
The expedition, however, did not succeed in passing to the east- 
ward of Cape Florida. 
An accurate knowledge of the currents and winds enabled 
the freebooters of the sixteenth century to carry on their depre- 
dations with impunity, and their successors, the wreckers of the 
Florida reefs and Bahamas, made use of their intimate know- 
ledge of the coasts, and of the winds and currents, to obtain 
commercial advantages, not always by the most honest methods. 
With the mapping of the reefs by the Coast Survey all this has 
disappeared, and the lighting of the great highway of the 
Straits of Florida has reduced to a minimum the dangers of 
navigation, though the Tortugas are still a favorite resort, even 
in broad daylight, for old ships properly insured. (Compare 
Figs. 172 and 34.) 
The captain of one of the Spanish vessels was carried south, 
off the coast of South America, by the current which sweeps 
from Cape St. Roque along the shores of Brazil, and involunta- 
rily discovered the Brazilian shore current. Though these dif- 
ferent currents were known to exist in the Atlantic, the most 
crude notions of their origin and course prevailed. (Fig. 172.) 
According to Columbus, at the equator the waters of the ocean 
moved westward with the heavens above, rolling over the fixed 
earth as a centre. It was only in the seventeenth century that 
physicists began to suspect a connection between the currents 
and the rotation of the earth, a view afterwards maintained by 
Arago and Humboldt. 
