288 DEPTHS OF THE OCEAN chap. 



metres (25 fathoms) below the surface between 6 a.m. and 2.20 

 P.M. In the forenoon the current ran east in the same manner 

 as at a depth of 10 metres ; about 8 a.m. the velocity was more 

 than 90 cm. per second (1.8 knot per hour); about 11 a.m. it 

 was slackening considerably, and at 2.20 p.m. it was merely 

 9 cm. per second (0.2 knot per hour) ; the current then set to 

 the north. The variations in velocity correspond to those 

 found at 10 metres. 



Similar results (Fig. 194, 3) were obtained at 91 metres (50 

 fathoms), where the current ran into the Mediterranean in the 

 forenoon with velocities attaining 105 cm. per second (2 knots 

 per hour) ; but between 2 and 3 p.m. it turned to the north-west, 

 that is, mainly towards the Atlantic and contrary to the current 

 at 10 metres. 



Fig. 194, 4, shows the results obtained by sending down the 

 current-meter with 183 metres (100 fathoms) of wire. The 

 observations were made between 6.40 a.m. and 11.26 a.m., and 

 all this time the current ran out from the Mediterranean in the 

 direction opposite to that of the higher layers, the greatest 

 measured velocity being rather more than 40 cm. per second 

 (0.8 knot per hour). The transition from the current running 

 into the Mediterranean to that running out must have been 

 somewhere above 100 fathoms. 



The observations with the apparatus out with 274 metres 

 (150 fathoms) of wire are particularly interesting (see Fig. 

 194, 5). They were made from 2.15 a.m. to 3.30 p.m., and 

 the current all that time ran west, from the Mediterranean into 

 the Atlantic. At 2.15 a.m. the enormous velocity of 227 cm. 

 per second (4.4 knots per hour) was observed ; at this time the 

 current at 10 metres had also a westerly set. Then the velocity 

 decreased ; at 8.49 a.m. — half a tide-period later — a velocity of 

 only 17.5 cm. per second (rather more than 0.3 knot per hour) 

 was measured ; at this time the current in the opposite direction 

 at 10 metres ran its fastest. Later on, the deep current 

 increased in velocity, running at 3.27 p.m. — after another half- 

 tide period — 83 cm. per second (1.6 knot per hour). There 

 was a similar difference between two successive tides at 

 274 metres and at 10 metres. These observations gave this 

 important result : that when the surface current ran fastest to 

 the east the under current setting west was at its slowest, and 

 vice versa. 



At 12.22 P.M. one of the current-meters was sent down with 

 366 metres (200 fathoms) of wire, but after working for ten and a 



