28 PASSAGE FROM MADEIRA 



opportunity of settling the origin of this plant, which is spread over the 

 whole ocean ; but my time did not permit me to make this deviation 

 from our direct course, and I hoped on my return to have ample 

 leisure for its exploration. 



On the 29th of September, we passed into discoloured water, as 

 green in appearance as that of fifty fathoms depth. On entering it the 

 thermometer fell one and a half to two degrees. The distance run in 

 it was about four hundred and fifty miles. Repeated casts of the deep 

 sea lead were had in from two to three hundred fathoms, but no bottom 

 found. The water was particularly examined for animalcula but 

 none were detected. On leaving it a rise of temperature took place of 

 two degrees ; and much phosphorescence was seen when we had 

 passed out of it. 



The first shoal searched for was the Maria Rock, said to be in 

 latitude 19° 45' N., and longitude 20° 50' W. In its neighbourhood 

 our position was carefully ascertained. The vessels were then spread 

 in open order, and a course sailed to pass directly over the spot. The 

 surface of the ocean visible was not less than twenty miles in latitude 

 with every opportunity which clear weather could afford. Good look- 

 outs were kept at the masthead, and there was a sufficient swell to 

 cause breakers on any shoal within fifteen feet of the surface. We 

 ran over the locality without perceiving any thing that indicated a 

 shoal. 



The situation of the Bom Felix Shoal, laid down about ten leagues 

 to the south of the above, was passed over in the same manner, 

 sounding repeatedly for bottom with three hundred fathoms of line, 

 but no appearance of a shoal was observed. 



The reported position of the Bonetta Rocks next claimed our 

 attention, in latitude 16° 32' N., and longitude 20° 57' W. After this 

 locality had been w r ell examined, a course was steered over its sup- 

 posed bearing from Bonavista, one of the Cape de Verde Islands. 

 The vessels of the squadron sounding every half hour during the night, 

 which was clear and bright moonYght.* 



On the night of the 6th of October, we hove to off the island of 

 St. Jago. Seldom have we seen the sea exhibit so much phospho- 



* Since our examination, 1 hav seen a letter from the American consul at Porto Praya, 

 F. Gardiner, Esq., detailing the wreck of the British ship Charlotte in 1841, and placing 

 this shoal in latitude 16° 17' N., longitude 22° 21' W., 84' in longitude and 15' in latitude 

 from the position I searched for it in ; whence it appears that it is the same reef on which 

 the Magdelaine was lost. I have no kind of doubt but that they ought all to be referred to 

 the Hartwell Reef. The same gentleman was confident at the time I saw him that the 

 Magdelaine had been los*. on the reef of that name. 



