If we refer to January, 1871, we shall find that that eruption was preceded by several earthquakes, among which were those of the months of October, November and December, in the previous year, that wrought such destruction in Calabria, and especially in the province of Cosenza; if we consider that as only the last phase, we shall find that it was preceded by great shocks of earthquake that devastated some regions of Greece.[3] The great quantity of lapilli which fell buried the scoriæ with which the Vesuvius cone was covered, so that it became somewhat more difficult to ascend to the summit, and much less difficult to descend. Having reached the top of the mountain, I found a large crater divided into two parts by what seemed a cyclopean wall. The two abysses had vertical sides, and revealed the internal structure of the cone. Their vertical depth was 250 metres; and beyond that I observed a sort of tunnel perforated in the rock, with a covering arch raised above the bottom of the eastern abyss about 12 metres, judging by the eye. The interior walls of the crater showed neither the usual stalactitic scoriæ nor sublimations, nor fumaroles, but alternate beds of scoriæ and of compact lava. The fumaroles and sublimations abounded, only about the brims of the craters. Hydrochloric and sulphuric acid and sometimes sulphuretted hydrogen affected respiration, and the temperature rose sometimes to 150 degrees. Various fissures about the brim of the double crater indicated prolongations downwards, which allowed me to descend with a rope, in order to examine the interior of the tunnel to which I have just alluded. The highest brim of the crater was fissured for a distance of 80 metres, and the greatest depth of fissure was at that place. By measurement with the barometer, we ascertained approximately (for only one barometer was used) that the height of the Vesuvian cone was somewhat diminished. Not only the Vesuvian cone, but the whole adjacent country appeared white for many days, as if covered with snow, when exposed to sunlight. This was due to the sea-salt contained in the ashes with which the surface was strewn.