AYLEN OR PORGAS BANK, ETC. 607 



the commander as to finding bottom ; for the U.S.S. Dolphin got a good sounding 

 of 3,828 fathoms, the deepest obtained in the cruize, a degree to the South of that 

 reported of 366 fathoms, and no bottom with J, 000 fathoms near that of 620 

 fathoms, and 3,080 fathoms has been found near that of 744 fathoms. 



ECHO BANK, lat. 21° 12' N., long. 58° 42' W. 

 Lieut. A. H. Bisschop GreeveHnk, of the Dutch vessel Echo, a very reliable 

 observer, reported as follows : — " On our passage from the West Indies to Europe, 

 in July, 1837, at about 4 p.m. of the 7th, a serpentine streak, of a dark brown 

 colour, was observed on the surface of the sea. Having lowered the boat, sound- 

 ings were found to exist, although in more than 30 fathoms." 



NICTHEKOY BANK, lat. 5° N., long. 47° 5' W. 

 In 1881, the captain of the Nictheroy reported that he found a depth of 52 

 fathoms, rocky bottom, in the above position, but a depth of 1,876 fathoms has 

 been fovmd a few miles to the eastward. 



Aylen or PoEGAS Bank, East of the Cape Verde Islands. 

 In the early charts of the Atlantic, this bank was shown as extending 150 miles 

 in length, North and South, with a breadth of 15 miles. Nothing more than this 

 appeared to be known of it, except that it was all deep water, and not dangerous 

 to shipping. It was unsuccessfully sought for by the Leven in 1819, and in some 

 later charts it was omitted for want of confirmation. However, the following is 

 the report of a cast of the lead taken from the steamer Birkenhead, on her voyage 

 to Ascension, vmder the command of Mr. J. B. Aylen, R.N., on November 11th, 

 1850. In lat. 17° N., long. 20° 3' 15", from careful and reliable observations, a 

 depth of 86 fathoms was found ; the bottom appeared to consist of pieces of shells 

 and sand, or small particles of coral. Mr. Aylen says, " I did not Hke heaving the 

 ship to, to take another cast, particularly as I considered myself on the edge of 

 the bank only, and that at noon, when on its centre, I would again try, which I 

 did without success with 90 fathoms of line." 



Besides this sounding, another of 164 fathoms was obtained, in 1819, by Capt. 

 Fremuiville, to the N.W. of the above cast, in lat. 18° 35', long. 21° 40'. 



The following is an extract from a log examined at the Meteorological Office : — 

 " Here is the position of Porgas Bank, according to the old charts ; we sounded 

 at noon in 17° 10' N., 20° 32' W., with 150 fathoms ; got no bottom." 



The followmg is from the log of H.M.S. Hijdra. "August 1st, 1868. In lat. 

 16° 17' N., long. 19° 43' W., sounded on the eastern edge of the alleged Porgas 

 iiank, obtaining 1,880 fathoms, oaze; noon, crossed the alleged position of Porgas 

 Bank, no indication of shallow water. In 16° 46' N., 19° 45' W., sounded on a 

 patch marked 86 fathoms Birkenhead, obtaining 1,850 fathoms, brown sand and 

 mud." This latter sounding is about 20 miles S.E. of the position of the 86 

 fathoms soimding of the Birkenhead, 



On May 10th, 1889, Capt. Russell, of the steamer Dalton, reported that from 

 lat. 17° 55' N., long. 24° 36' W., to lat. 19° 30' N., in the position ascribed to 

 Porgas Bank, the colour of the water appeared to indicate depths less than 80 

 fathoms, and that he had observed the same appearance here for the past 3 years. 



DORIC BANK, lat. 18° 57' N., long. 18° 15' W. 

 In 1890, a sounding of 56 fathoms was obtained from the telegraph steamer 

 Doric, when about 100 miles westward of Cape Mirik ; depths of 1,500 and 1,600 

 fathoms were found around it, at 17 miles distant. In 1891, the steamer Silver- 

 town took four soundings in this locahty, and found regular depths, 1,494, 1,497 

 1,498, and 1,509 fathoms. 



