NARRATIVE OF THE CRUISE. 159 



ward, until it reached 41° on the 21st May in lat. 42° 10' N., long. 63° 39' W. From 

 this position the change was more rapid, as at 7 a.m. on the 22nd, in lat. 41° 19' N., 

 long. 63° 11' W., the temperature at the surface was 57°*5. It is remarkable 

 that although the ship remained stationary the whole of that day, sounding 

 and dredging, and although no current whatever could be detected whilst so cm- 

 ployed, yet the temperature at the surface increased from 57°'5 at 7 a.m. to 62° - 5 

 at 4 p.m. It is true that the sky was clear, and that the power of the sun was there- 

 fore great, still it will be seen, by referring to the meteorological register, that the 

 maximum temperature of the air was.61°"0, or l c- 5 below that of the water, although 

 the wind was from the southward. 



At 6 p.m. on that day, having completed the observations, the vessel proceeded towards 

 Bermuda, the surface water retaining its temperature of 62°"5 until 8 p.m., after which it 

 fell to 58°"0, and at midnight to 54°"0, but at 1 a.m. on the 23rd May it rose again to 

 ()4° - 8, and at 1.30 a.m. to 68°. At 4 a.m. the surface water attained a temperature of 

 70°'5, which it retained until 9 a.m., when a line of ripple on the water was passed, 

 and the temperature fell to 66 Q, 5. At 10.15 a.m. on the 23rd the ship stopped to 

 sound, remaining stationary until 5 p.m. ; during this time the surface water, which was 

 ascertained, by astronomical observation, to be running to the southward (confirmed 

 by having to steam to the northward to keep the line perpendicular), varied in 

 temperature from 67° - 2 to 68°'0. The position at this time was lat. 39° 44' N., 

 long. 63° 22' W., and the serial temperature sounding placed the isotherms of 60°, 50°, 

 and 40° at precisely the depths that they occupied at Bermuda, then distant 450 miles, 

 and these depths they steadily retained for the remainder of the section (see 

 Diagram 2). 



At 5 p.m. on the 23rd the course was continued towards Bermuda, and the surface 

 temperature was found to vary from 67°"0 to 71°'2 until 8 a.m. on the 24th, when it 

 rose to 7 3° "5, and remained steady until 6 p.m. A serial temperature, taken at 4 p.m. 

 in lat. 38° 1G' N., long. 63° 17' W„ showed that the temperature of 73° continued 

 to a depth of 50 fathoms, but that between 50 and 75 fathoms a decrease of 5° - 5 

 took place. The current, as ascertained by difference between the position calculated 

 from D.B. and observation between 9.30 a.m. and 4 p.m. was easterly, its rate being 

 lg miles per hour. Unfortunately, the weather on the 24th was unfavourable either for 

 sounding or dredging, so that it was impossible to test the current by mooring a boat. 



After G p.m. on the 24th the surface temperature again became variable, falling to 

 G4' - 5 by 8 a.m. on the 25th, and varying between 64° - 5 and 69° - 5 until 4 a.m. on the 

 26th, when it again rose to 70 o, 5 and at 2 p.m to 73 0, 5, but the serial temperatures on 

 that day (at Station 53) showed that the warm water was quite superficial, as at 25 

 fathoms the temperature was 69°, and at 50 fathoms 66°, whereas on the 24th the 

 temperature of 73° was observed at the latter depth. 



