464 CURRENTS AND WHALING. 



rature, a submarine stream still appears to exist. In lieu of the former 

 we have the current familiarly known as the African Current, by its 

 causing so many distressing wrecks on that coast, and to which atten- 

 tion has often been drawn by the captivity and cruel slavery to which 

 their crews have been subjected. 



As has been seen in the Narrative, but little surface current was 

 found on our voyage from Madeira to the Cape de Verdes ; but the sub- 

 marine stream was still found, as was shown by the low temperatures 

 of the deep-sea soundings. At, and in the neighbourhood of the latter 

 islands, and between them and Cape Verde on the African coast, a 

 strong surface current is felt. In endeavouring to account for this 

 remarkable circumstance of the creation of a current, and its increased 

 velocity, of which every navigator must be aware when in the 

 neighbourhood of many islands, and the effects of which we have often 

 experienced in our long voyage, I shall now advert to the cause which 

 I think is quite sufficient to produce the effect; and that is the accumu- 

 lation of water caused by the obstructions that islands offer to the 

 onward flow of submarine streams; thus raising the level of the ocean 

 in their vicinity, and consequently a tendency to run off, and thereby 

 cause a current where none was perceptible before, or an increased 

 velocity in that which was felt. 



To this cause, then, I believe the currents around the Cape de 

 Verde Islands owe their origin, as well as all others prevailing near 

 islands and banks; and as corroborative proof of this I will mention the 

 fact that where no submarine polar stream exists, permanent currents 

 are not found. This will, I trust, be amply shown in the sequel. 



That remarkable current along the coast of Guinea, from which it 

 derives its name, passing Cape Palmas, and flowing into the Bight of 

 Benin, I attribute to the same cause. This current is in the immediate 

 vicinity of the Equatorial Stream, but runs in an opposite direction, 

 and for a long distance parallel to it. Of this current the following 

 remarks were made by Colonel Sabine, when he passed it in H. B. M. 

 ship Pheasant, Captain Clavering, in 1822. 



" In the voyage between Cape Mount and Cape Three Points, in 

 April and May, 1822, the Pheasant's progress appears to have been 

 accelerated one hundred and eighty miles by the current called the 

 Guinea Current, which, in the season when the southwest winds pre- 

 vail on this part of the coast, runs with considerable velocity, in the 

 direction of the land, from Cape Palmas to the eastern part of the 

 Gulf of Guinea. The breadth of this current, abreast of Cape Palmas, 

 varies with the season, and has been found as much as one hundred 

 and eighty miles ; but, in its subsequent course to the eastward, it 



