THE CLIMATES OF THE SEA. 393 



732. TJiefogs of Newfoundland. — By its discovery we have clearly 

 unmasked the very seat of that agent which produces the Kew- 

 foundiand fogs. It is spread out over an area frequently em- 

 bracing several thousand square miles in. extent, covered with 

 cold water, and surrounded on three sides at least with an im- 

 mense body of warm. May it not be that the proximity to each 

 other of these two ver}^ unequally heated surfaces out upon the 

 ocean would be attended by atmospherical phenomena not unlike 

 those of the land and sea breezes ? These warm currents of the 

 sea are powerful meteorological agents. I have been enabled to 

 trace in thunder and lightning the influence of the Gulf Stream 

 in the eastern half of the Atlantic as far up as the jDarallel of 55° 

 Is., for there, in the dead of winter, a thunder-storm is not un- 

 usual. 



733. Aqueous isothermal lines. — These isothermal lines of 50^, 

 G0°, 70°, 80^, etc., may illustrate for us the manner in which the 

 climates in the ocean are regulated. Like the sun in the ecliptic, 

 they travel up and down the sea in declination, and serve the 

 monsters of the deep for signs and for seasons. 



734. The meeting of cool and icarm waters. — It should be borne 

 in mind that the lines of separation, as drawn on Plate IX., 

 between the cool and warm waters, or, more properly speaking, 

 between the channels representing the great polar and equatorial 

 flux and reflux, are not so sharp in nature as this plate would 

 represent them. In the first place, the plate represents the mean 

 Dr average limits of these constant flows — polar and equatorial ; 

 whereas, with almost every wind that blows, and at every change 

 of season, the line of meeting between their waters is shifted. 

 In the next place, this line of meeting is drawn with a free hand 

 on the plate, as if to represent an average ; whereas there is 

 reason to believe that this line in nature is variable and unstable 

 as to position, and as to shape rough and jagged, and oftentimes 

 deeply articulated. In the sea, the line of meeting between 

 waters of difl"erent temperatures and density is not unlike the 

 sutures of the skull-bone on a grand scale — very rough and 

 jagged ; but on the plate it is a line drawn simpl}'" with a free 

 hand, merely for the purpose of illustration. 



735. The direction of aqueous isotherms on opposite sides of the sea. 

 — Xow, continuing for a moment our examination of Plate lY., 

 we are struck with the fact that most of the thermal lines there 

 drawn run from the western side of the Atlantic towards the 



