Gulf-Stream on the Coasts of Europe. 



271 



peatedly driven back, and detained in the ports of the Chan- 

 nel. The following memorandum exhibits her position at 

 noon on each day of her subsequent voyage from Plymouth 

 to Madeira, and from thence to the Cape Verd Islands, the 

 temperature of the air in the shade, and to windward, and 

 that of the surface of the sea. It also exhibits, in comparison, 

 the ordinary temperature of the ocean at that season, in the 

 respective parallels which Major Rennell has been so kind as 

 to permit me to insert on his authority, as an approximation 

 founded on his extensive inquiries. The last column shows 

 the excess or defect in the temperature observed in the Iphi- 

 genia's passages. 



It is seen, from the preceding memorandum, that, in the 

 passage from Plymouth to Madeira, the Iphigenia found the 

 temperature of the sea between the parallels of 44J° and 33§° 

 several degrees warmer than its usual temperature in the same 

 season, namely, 3°2 in 44J° increasing to 6° in 39°, and 

 again diminishing to 4° in 33§°, whilst, at the same period, 

 the general temperature of the ocean in the adjoining paral- 

 lels, both to the northward and to the southward, even as far 

 as the Cape Verd Islands in 19|°, was colder by a degree and 

 upwards than the usual average. The evidence of many care- 

 ful observers, at different seasons, and in different years, 

 whose observations have been collected and compared by 

 Major Rennell, has satisfactorily shewn that the water of the 

 Gulf-Stream, distinguished by the high temperature which it 

 brings from its origin in the Gulf of Mexico, is not usually 



