46 F. L. Ekman, 



dency to flow out to the North and South is thus counterbahuiced, 

 and at the same time it is continually driven towards the west, until 

 that motion is limited by encountering a continent. The effect of the 

 solar heat upon the sea-water must therefore here be collected as if to 

 a kind of focus, for the level will here be elevated by the dilatation, 

 that the water has undergone in its passage over the whole region just 

 mentioned, and by the trade-winds, heaping up the warmed water on 

 the coast. This water can here flow off" with so much the more force, 

 as the eff'ect of the said winds in the vicinity of continents is debilita- 

 ted and becomes irregular. Instead of the relatively thin, weak and 

 easily chilled surface-stream, which the heat could have produced, if the 

 stream had been spread over the ocean's whole breadth, now appear the 

 ocean-currents, known under the names of the Gulf-stream and the Kuro 

 Sivo, which as well by their power as their other properties have beyond 

 others attracted universal attention; freely floating streams of warm dark- 

 blue water, moving with considerable velocity in a bed of more diluted, 

 cold, and discoloured water from higher latitudes, which they draw to 

 themselves powerfully by mechanical reaction, and with which they pre- 

 sent the most marked contrast. Their contracted form and great velo- 

 city render them peculiarl}^ fit to convey to higher latitudes the solar 

 warmth, which the sea has acquired between the tropics. The amount 

 of heat which they themselves in consequence of mechanical resistance 

 develope, even though small relatively to the mass of water, must ne- 

 vertheless in such respects be greater than that of most other ocean- 

 currents. During their progress in a North-Easterly direction, they in- 

 crease vastly in mass, but become less rapid and less distinctly defined, 

 in full accordance with the general laws of a surface-current's motion, 

 which I have endeavoured to develope in the preceediug pages. 



From the causes assigned as the origin of the Gulf-streams, if we 

 may use that name in a general sense, one would evidently be led to 

 suppose that the Gulf-stream of the Pacific ought be far more powerful 

 than that of the Atlantic. I need not touch upon the known circum- 

 stances relating to the contour of the continent's eastern coast-line, 

 which so essentially contribute to increase the intensity of the Atlantic 

 Gulf-stream and to reduce the lateral efflux of the equatorial stream, 

 before the current has yet reached the regions, where the Gulf-stream 

 properly so called developes itself. Neither can the great quantity of 

 river-water, which is poured out into the Gulf of Mexico, or is carried 

 thither by the equatorial stream, fail to exercise an influence on the 



