Vol. 62.] THE RECENT ERUPTION OF VESUVIUS. 481 



and their unsinged leaves and blossoms form a gay canopy over the 

 stream of smoking lava, which surrounds them up to a height of 7 

 or even 10 feet, and flows onward. It may be that around such trees 

 a scoriaceous crust forming instantaneously on the lava prevents 

 immediate combustion, and they merely wither away slowly from 

 desiccation. 



[During the 7th and 8th of April the sea-level was lowered all 

 along the neighbouring coast, by as much as 12 inches near Portici, 

 and as little as 6 near Pozzuoli, and has not so far (April 13th) 

 returned to its previous level. This would imply that there has 

 been a real elevation in this part of the earth.] 



It remains to mention that the lava, lapilli, and dust of this 

 eruption are of the usual leucotephritic character observed in all the 

 eruptions of Vesuvius, from 1872 until the present day. 



The eruption of which a brief account has been given took place 

 in clear and calm weather, while the barometer was high, and the 

 sea was quite exceptionally smooth. The maximum of eruptivity 

 coincided almost exactly with the full moon. The volcanoes of the 

 Phlegraean Fields and of the Islands remained in their normal 

 condition, which goes to prove that the shocks recorded in March at 

 Ustica, and the Calabrian earthquakes of last September, had no 

 connexion whatever with the phenomena here described. 



Next to the great eruptions of 79 a.d. and 1631, I believe that 

 the recent eruption is one of the greatest that history records from 

 Vesuvius. 



Postscript. 



[Up to May 1905 the principal cone of Vesuvius had reached an 

 altitude of 4,362 feet above the sea, being thus 650 feet higher than 

 the crest of Monte Somma (3,712 feet above sea-level). In 

 consequence of the eruption of April 4th/8th, 1906, and especially 

 after the great explosions and fissurings which took place during the 

 night of the 7th to the 8th, the cone of Vesuvius has changed 

 completely in shape, being obliquely truncated by a new crateric 

 rim, which on the south-west attains an altitude of 4,133 feet, and 

 on the north-east an altitude of 3,673 feet above sea-level. This 

 obliquity of the crater and of the explosions, directed north-east- 

 ward, as if proceeding from a siege-mortar trained in that direction, 

 contributed far more than the prevailing wind to the destruction 

 of Ottajano by masses of lapilli and scoriae. The crater thus 

 formed opens upward like a cup with oblique sides, and then plunges 

 downward like a chimney with vertical walls, of which the depth 

 cannot be ascertained beyond 650 feet down. The external crateric 

 rim reaches perhaps a diameter of 1640 feet, and the throat 

 of the internal chimney can hardly measure less than 1000 feet in 

 diameter. 



The great explosions hurled into the air (together with the 

 pulverized magma, and the material of the fissured cone crumbled 

 into dust) blocks and fragments torn out of the cone, which had 



