354 Meteorological and Hydrographical 



Avater fell l°-9 ; and on tlie 22d, while a NE. current of the 

 same specific gi-avity as on the 21st continued, the diminu- 

 tion of temperature was 0"'9 only. 



The cause of the extraordinary whirl on the 20th and 21st 

 it is not easy to make out. The ship was then about east from 

 the Bermudas, and not very distant from a cluster of rocks 

 which are often mistaken for these islands. It is possible that 

 irregularities of the bed of the sea, connected with these, might 

 have produced the eddies in question. 



The current on the 23d was, N. 84° E., ten miles, and the 

 water had a specific gravity of 102796, almost identical with 

 those of the 19th and 20th ; and on the 24th the ship was in 

 the Gulf Stream, as laid down in the chart. The specific 

 gravity of the water was then 1-02770, and on the following 

 two days it increased a little, the temperature at the same 

 time diminishing considerably, especially on the 26th, as the 

 northern edge of the stream was approached. As the NW. 

 currents between the Antilles and Bermuda flow into the 

 space between the latter and southern margin of the Gulf 

 Stream, that portion of the water which reaches the edge of 

 the stream must be gradually turned to the eastward along 

 with the stream : the high specific gravity of the water on the 

 23d (which did not follow the regular course of the stream) 

 can thus be accounted for ; and farther, a rational explanation 

 will be found for the rapid enlargement the stream itself un- 

 dergoes a little to the northward of the Bahamas. An alloAV- 

 ance has been made for the drift of the Gulf Stream on the 

 24th and 25th ; but as I am unable to state the amount, I have 

 given the numbers in the table without alteration. 



On the 27th the specific gravity of the water was only 

 102729, and the temperature fell 3°-8 from that on the pre- 

 ceding day, while the drift was N. 68° W., six miles ; all in- 

 dicating that the Gulf Stream had been passed. 



It is iTsually supposed that, at some distance to the westward 

 of Ireland, a part of the Gulf Stream is directed to the NE., 

 and flowing along the western coast of the British Islands, 

 even reaches that of Norway. The drift of the ship, from the 

 1st to the 3d of March, seems to afford evidence of this ; but, 

 from the 27th February, the wind had been so variable in 



