VOLCANIC REGIONS. 613 



IJ minute ; it was evidently the effect of some volcanic agency, and was 

 80 distinctly felt as to alarm all hands. There was nothing peculiar in 

 the appearance of sea or air. The weather was squally, with showers." 



Captain Whitmore, of the Sea Serpent, December 29th, 1859, struck, as 

 he supposed, on a coral reef, in lat. O'' 29' N., long. 28° 30' W., in con- 

 sequence of which he put into Rio. He sounded immediately, and found 

 no bottom, but afterwards found his false keel and copper injured. 



The Russian sloop of war Passodnik struck, as was supposed, on the 

 same shoal, about twenty-four hours before the Sea Serpent, but this 

 proves the nature of the occurrence. 



The Prince, James Thomas, commander, December 11th, 1853, in lat. 

 0° 54' N., long. 26° 50' W., smooth water, suddenly felt a grinding tremor 

 go through the vessel, as if dragging over something rough and yielding. 

 It continued for about the ship's length, but did not stop her way through 

 the water. The ship did not strike. 



The ship Maid of Judah felt a slight shock September 15th, 1855, in 

 lat. 1° 30' N., long. 25^° W. Strong swell from the southward. 



On the night of July 1st, 1886, Capt. Rood, of the barque Antwerp, felt 

 a shock on or near the Equator, in long. 26° 55' W. 



On November 16th, 1886, Capt. Wakeman, of the barque BanTcfields, in 

 lat. 0° 50' N., long. 29° 54' W., felt two severe shocks of 16 to 20 seconds, 

 separated by an interval of 20 minutes. The vessel trembled greatly, and 

 a rumbling noise was heard, as though dragging over shingle. The sky 

 was clear, and the weather fine but sultry, with a high confused sea. 



The barque Eleanor, Captain G. A. Findlay, March 26th, 1861, at 

 10 a.m., felt a shock as if something very heavy was being rolled about 

 the decks, or as if the ship had gone over some rough ground ; it made 

 the vessel tremble only for a few seconds. A rumbling noise was heard, 

 like distant heavy thunder. Weather remarkably fine ; lat. 0° 44' N., 

 long. 21° 19' W. Great quantities of fish and sharks around the ship. 



These instances, with the others, will afford ample evidence of the 

 general nature and locality of these volcanic shocks.' We have limited 

 the instances above given' to this particular area on the Equator ; but 

 there appears to be either an extension of this action far to the north- 

 ward, or else there is a separate area, for volcanic shocks have been felt 

 as far North as 23° 30' N., and long. 58° 0' W. ; and from the almost 

 continuous line of discoloured and peculiar water that extends from the 

 Equator to this position, as will be presently stated, we are led to infer 

 that there is a line of volcanic action trending parallel to the range of 

 the Antilles. 



The depth, however, is very great, and there is now not any reason for 

 supposing that any shoal exists. Lieutenant Lee and others have found 

 depths exceeding 2,000 fathoms over most of the region in question ; and 

 this is another evidence of the wonderful force of these shocks, which 

 can be transmitted through a stratum of water 12,000 feet and upwards 

 in thickness. 



We now proceed to give a few reports of shocks experienced in other 

 regions of the North Atlantic, many of them taken from records on the 

 U.S. Pilot Chart of the North Atlantic Ocean. 



