On the Gulf Stream and Currents of the Sea. 169 



parallels of these two places, its rate of motion around the axis of 

 the earth, is reduced from nine hundred and twenty five* to seven 

 hundred and fifty eight miles the hour. 



Therefore this immense volume of water, in passing from the 

 Bahamas to the Grand Banks, meets with an opposing force in 

 the shape of resistance, sufficient in the aggregate, to retard it two 

 miles and a half the minute, and this only in its eastwardly rate. 

 There is doubtless another force qnite as great retarding it to- 

 wards the north, for its course shews that it is the resultant of 

 two forces acting in different directions. If the former resistance 

 be calculated according to received laws, it will be found equal 

 to several atmospheres, and by analogy, how inadequate must the 

 pressure of the gentle trade winds be to such resistance, and to 

 the effect assigned them? If therefore in the proposed enquiry, 

 we search for a propelling power, no where but in the higher 

 level of the gulf, we must admit, in the head of water there, the 

 existence of a force sufficient at least to overcome the resistance 

 required to reduce from two miles and a half, to a few feet per 

 minute, the velocity of a stream that keeps in perpetual motion 

 one fourth of all the water of the Atlantic Ocean. 



The facts from observation on this interesting subject, afford 

 us at best but a mere glimmer of light, by no means sufficient to 

 make my mind clear as to a higher level of the Gulf, or as to the 

 sufficiency of any other of the causes assigned for this wonderful 

 stream. If it be necessary to resort to a higher level in the Gulf, 

 to account for the velocity off" Hatteras, I cannot perceive why 

 we should not, with like reasoning, resort to a higher level oflf 

 Hatteras also, to account for the velocity off the Grand Banks, 

 and thus make the Gulf Stream a descending current, and by the 

 reductio ad absnrdem, show that the trade winds are not adequate 

 to the effect ascribed. 



When facts are wanting, it often happens that in their stead 

 hypothesis will serve all the purposes of illustration. Let us 

 therefore suppose a globe of the earth's size, having a solid nu- 

 cleus and covered all over with water two hundred fathoms deep, 

 and that every source of heat and cause of radiation are removed, 

 so that its fluid temperature becomes constant and uniform 



* Or 915-26 to 758 60. On the latter parallel, the current has a set to the east 

 of one mile and a half the hour; making the true east velocity seven hundred 

 and sixty miles the hour. 



Vol. xLvii, No. 1.— April-June, 1844. 22 



