Page:Popular Science Monthly Volume 25.djvu/382

 of July, of the ship (on board which he was returning to England) through extensive fields of pumice spread over the ocean north and south as far as the eye could reach. The vessel passed the volcano on the 9th, but till the evening of the 10th, when the steamer would be about a degree to the west (a little northerly) of her noon position, which was 102° 25' east longitude, 6° 20' south latitude, no pumice was observed. During the whole of the 1 1th the vessel was surrounded by the pumice-sheet, which about noon of the 12th, in 93° 54' east longitude, 5° 53' south latitude, suddenly terminated, shortly after it had appeared in greatest amount, while a current had been encountered after leaving the entrance to the straits, running against the ship's course at the rate of a quarter of a mile an hour. The pumice -nodules were considerably worn, but many pieces were observed as large as a child's head. Several lumps were picked up infested with barnacles, of from one to one and a half inch in length, which represented at least some four or five weeks' growth.

The specimens of pumice obtained at sea have been submitted to Professor Judd and the committee appointed by the Royal Society for the examination of the phenomena connected with the eruption. If, on analysis, they should prove different in composition from specimens obtained directly from the volcano, a different origin will have been established for them; but, should both turn out to have identically the same components, it will not necessarily prove that both have come from the same crater. The Peninsular and Oriental Company's steamer Siam, on her voyage from King George's Sound to Colombo, sailed for four hours, on August 1st, through a similar "lava" (puraice) sheet, in latitude 6° south, and 89° east longitude, the nearest land, the coast of Sumatra, being seven hundred miles off, and the current then running eastward at from fifteen to thirty miles a day. The soundings at the spot reached two thousand fathoms. Mr. Forbes, who incidentally referred to the eruption when reading his paper before the society on the 28th of January last, suggested that the sounds heard in Batavia on the 20th of May, which were altogether unperceived at spots so near Krakatau as Anjer, Merak, and Telok-betong, which would be inexplicable if they really originated there, were the result of a submarine eruption in the Indian Ocean, somewhere southwesterly from Java Head; and that the tremors were propagated thither perhaps by continuous strata connecting the locale of the outburst with Batavia, Buitenzorg, and more especially with the hills to the southwest, where the manifestations were so distinctly perceived. We know from Mr. Darwin's and Mr. Forbes's observations, that the center of volcanic disturbance does exist in that direction, in the Keeling Atoll, situated six hundred miles west by south from the mouth of the straits. Whether or not anything unusual has been experienced in these