THE GULF STREAM. 41 



one milo or one hundred miles in length, the effect of diurnal 

 rotation is the same ; and, whether the road be long or shoi-t, the 

 tendency to run off, as you cross a given parallel at a stated rate 

 of speed, is the same ; for the tendency to fly off the track is in 

 proportion to the speed of the train, and not at all in proportion 

 to the length of the road. Now, vis inertice and velocity being 

 taken into the account, the tendency to obey the force of this 

 diurnal rotation, and to trend to the right, is proportionably as 

 great in the case of a patch of sea-weed as it drifts along the 

 Gulf Stream, as it is in the case of the train of cars as they speed 

 to the north along the iron track of the Hudson Eiver, or the 

 North- Western railway, or any other railway that lies nearly 

 north and south. The rails restrain the cars and prevent them 

 from fl^'ing off; but there are no rails to restrain the sea- weed, 

 and nothing to prevent the drift matter of the Gulf Stream from 

 going off in obedience to this force. The slightest impulse 

 tending to turn aside bodies moving freely in water is imme- 

 diately felt and implicitly obeyed. 



114. Drift-wood on the Mississijppi. — It is in consequence of this 

 diurnal rotation that drift-wood coming down the Mississippi is 

 so very apt to be cast upon the west or right bank. This is the 

 reverse of what obtains upon the Gulf Stream, for it flows to the 

 north; it therefore sloughs off (§ 111) to the east. 



115. Effect of diurnal rotation upon. — The effect of diurnal rota- 

 tion upon the winds and upon the currents of the sea is admitted 

 by all — the trade-winds derive their easting from it — it must, 

 therefore, extend to all the matter which these currents bear 

 with them, to the largest iceberg as well as to the smallest spire 

 of grass that floats upon the waters, or the minutest organism 

 that the most powerful microscope can detect among the im- 

 palpable particles of sea-dust. This effect of diurnal rotation 

 upon drift will be frequently alluded to in the pages of this work. 



116. Formation of the Grand BanJcs. — In its course to the north, 

 the Gulf Stream gradually tends more and more to the eastward, 

 until it arrives off the Banks of Newfoundland, where its course 

 becomes nearly due east. These banks, it has been thought, 

 deflect it from its proper course, and cause it to take this turn. 

 Examination will prove, I think, that they are an effect, certainly 

 not the cause. It is here that the frigid current already spoken 

 of (§ 85), and its icebergs from the north, are met and melted by 

 the warm waters of the Gulf. Of course the loads of earth, 



