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the Mediterranean." By John Davy, M.D. F.R.S. Assistant Inspec- 

 tor of Army Hospitals. 



The first intelligence of the breaking out of the volcano, which is 

 the subject of the present paper, was brought to Malta, on the 16th 

 of July last, by a merchant vessel. It was confirmed soon after by 

 Captain Swinburne, of H. M.S. Rapid, who hadsucceededin approach- 

 ing very near the island. The crater of the volcano, which was in 

 great activity, was then only a few feet above the level of the sea. 

 Several shocks of an earthquake had been felt near the same spot 

 about a month before the eruption. The volcano continued active 

 till the 16th of August, and the island it was forming gradually en- 

 larged in all its dimensions ; but since that period there has been no 

 fresh eruption. In the end of August, a survey of the island was 

 carefully made by Captain Wodehouse, R.N. of H.M. brig Ferret ; 

 and a plan drawn by him is annexed to the present paper. The cir- 

 cumference of theisland is about 3240 feet, and its greatest height 107 

 feet ; the circumference of its crater is about 780 feet. The surface 

 of the island is composed entirely of ashes and cinders, without any 

 lava. The crater contained turbid salt water, having a temperature 

 of 200° Fahr. and emitting a constant supply of gas. The water in 

 the immediate neighbourhood of the island was very shallow, not ex- 

 ceeding three or four feet, and the crater was rapidly filling up by 

 the falling in of its margin. 



The author could notlearn that anything unusual had been noticed 

 as having occurred in any of the neighbouring volcanic regions, 

 either at the time of the eruption or immediately antecedent to it. He 

 describes the phenomena, which fell under his own observation, on 

 a visit which he made to the island on the 5th of August. During the 

 most violent eruptions, a large quantity of dense white vapour, re- 

 sembling snow or bleached wool, rose to a great height in the atmo- 

 sphere, and assumed various extraordinary forms; this was followed by 

 columns of perfectly black matter, rising to the height of three or four 

 thousand feet, and spreading out very widely, even to windward. The 

 subterranean sounds attending the eruptions were not very loud, and 

 were much exceeded by that of the electrical explosions accompany- 

 ing the lightning, which was seen to dart in various directions in the 

 atmosphere of the eruption. To leeward of the volcano, the sea was 

 much discoloured by the admixture of ashes and fine dust, and an 

 abundance of light cinders were floating on its surface. Even when 

 the author was enveloped in the dark cloud of ashes falling from the 

 volcano, not the smallest odour of bitumen, of sulphuretted hydro- 

 gen, or of sulphureous or any other acid, was perceptible ; nor was 

 any inconvenience felt in respiration. No appearance of flame, and 

 but little light, was exhibited during these eruptions. 



The solid products ejected from the volcano appeared, on examina- 

 tion, to differ more in form than in chemical composition; and were 

 found to consist of alumina, lime, magnesia, and silex, coloured by 

 protoxide of iron, and without any potash. With the exception of 

 small masses of vesicular basalt, similar to the common lava of Etna 

 and Vesuvius, these materials exhibited no crystalline structure. The 



