GULF STREAM, CLIMATES, AND COIVrMERCE. 53 



paper on cuiTents,* Mr. Bedfield states, that in 1831 the harbour 

 of St. John's, Newfoundland, was closed vdth. ice as late as the 

 month of June ; yet who ever heard of the port of Liverpool, on 

 the other side, though 2^ farther north, being closed with ice, even 

 in the dead of ^vinter ? 



154. The Thermal Chart (Plate lY.) shows this. The isother- 

 Miidnessofanork- i^al liues of 60^, 50°, ctc, starting off fi'om the pa- 

 ney ^vinter. rallcl of 40° ucar the coasts of the United States, run 

 off in a north-eastwardly direction, sho^\dng the same oceanic tem- 

 peratme on the European side of the Atlantic in latitude 55° or 

 60° that we have on the western side in latitude 40°. Scott, in 

 one of his beautiful novels, tells us that the ponds in the Orkneys 

 (latitude near 60°), are not frozen in winter. The people there 

 owe their soft climate to this grand heating apparatus, and to the 

 latent heat of the vapours from it which is liberated dming the 

 precipitation of them upon the regions round about. Driftwood 

 from the West Indies is occasionally cast upon the islands of the 

 North Sea and Northern Ocean by the Gulf Stream. 



155. Nor do the beneficial influences of this stream upon climate 

 Amount of heat daily end hcrc. The "West Indian ArchipelaGfo is encom- 



escaping through the , • 1 "L u T, • r • l J T j.i 



Gulf Stream. passcd ou onc Side by itscnam oi islands, and on the 



other by the Cordilleras of the Andes, contracting with the Isthmus 

 of Darien, and stretching themselves out over the plains of Central 

 America and Mexico. Beginning on the summit of this range, Ave 

 leave the regions of perpetual snow, and descend first into the 

 tierra temijlada, and then into the terra caliente, or bm-ning land. 

 Descending still lower, we reach both the level and the smface of 

 the Mexican seas, where, were it not for this beautiful and benign 

 system of aqueous circulation, the peculiar features of the surround- 

 ing comitry assure us we should have the hottest, if not most pes- 

 tilential climate in the world. As the waters in these two caldrons 

 ])ecome heated, they are boiTie off by the Gulf Stream, and are re- 

 placed by cooler currents through the Caribbean Sea ; the surface 

 water, as it enters here, being 3° or 4°, and that in depth even^ 

 40° cooler than when it escapes from the Gulf. Taking only tMs 

 difference in smface temperatm-e as an index of the heat accumu- 

 lated there, a simple calculation will show that the quantity of heat 



* American Journal of Science, vol. xiv., p. 293. 



t Temperature of the Caribbean Sea (from the journals of Mr. Dunsterville) : 

 Surface temperature: 83^ September; 84^, July; 83"-86|-\ Mosquito Coast. 

 Temperature in depth ; 48^ 240 fathoms ; 43^ 3*80 fathoms ; 42^, 150 fathoms : 

 43\ 500 lathoms. 



