.8 
THE ATLANTIC CURRENTS. 
to 50 leagues. The rapidity of the current is from three to 
five miles an hour where the stream is narrowest, and is only 
one mile as it advances towards the north. The waters of 
the Mexican Gulf, forcibly drawn to north-east, preserve 
their warm temperature to such a point, that in 40 and 41 
degrees of latitude I found them at 22'5'' (18° It.) when, 
out of the current, the heat of the ocean at its surface 
was scarcely 17'5° (14° R.). In the parallel of New York 
and Oporto, the temperature of the Gulf-stream is conse- 
quently equal to that of the seas of the tropics in the 18th 
degree of latitude, as, for instance, in the parallel of Porto 
Rico and the islands of Cape Verd. 
To the east of the port of Boston, and on the meridian 
of Halifax, in latitude 41° 25', and longitude G7°, the cur- 
rent is near 80 leagues broad. Prom this point it turns 
suddenly to the east, so that its western edge, as it bends, 
becomes the western limit of the running waters, skirting 
the extremity of the great hank of Newfoundland, which 
M. Yolney ingeniously calls the bar of the mouth of this 
enormous sea-river. The cold waters of this hank, which 
according to my experiments are at a temperature of 8'7° or 
10° (7° or 8° B.) present a striking contrast with the waters 
of the torrid zone, driven northward by the Gulf-stream, 
the temperature of which is from 21° to 22'5° (17° to 18° E.) . 
In these latitudes, the calorie is distributed in a singular 
manner throughout the ocean ; the waters of the hank are 
9’4° colder than the neighbouring sea ; and this sea is 8° 
colder than the current. These zones can have no equili- 
brium of temperature, having a source of heat, or a cause 
of refrigeration, which is peculiar to each, and the influence 
of which is pennament. 
Prom the bank of Newfoundland, or from the 52nd degree 
of longitude to tho Azores, the Gulf-stream continues its 
course to east and east-south-east. The waters are still 
acted upon by the impulsion they received near a thousand 
leagues distance, in the straits of Plorida, between the island 
of Cuba and the shoals of Tortoise Island. This distance 
is double the length of the course of the river Amazon, from 
Jacn or the straits of Manseriehe to Grand Para. On tho 
meridian of the islands of Corvo and Plores, the most western 
of the group of the Azores, the breadth of the current is 
