244 G. Poulett Scrope — On Vesuvius. 



11. — Notes on the late Eruption of Vesuvius. 

 By G. Poulett Scrope, F.R.S., F.G.S., etc., etc. 



THE Eruptions of Vesuvius naturally create a wider and deeper 

 interest tkan those of any other volcano, owing to the mountain 

 lying within sight and hearing of one of the most populous and 

 frequented cities of Europe. And in these days of telegraphs and 

 newspaper correspondence the mingled feelings of alarm and admi- 

 ration which these phenomena excite at Naples are rapidly spread 

 over the civilized world, tinged with all the exaggerations and em- 

 bellishments that the imagination of writers, who, probably, witness 

 an eruption for the first time, can bestow on them. 



This has been in a marked degree the case with the recent eruption, 

 which, beginning on the 26th of April, began to decline on the 28th, 

 and terminated on the 2nd of May, and therefore in point of dura- 

 tion by no means equalled ^several outbursts of the same mountain 

 that have occurred during the last century. That of 1793-4 lasted a 

 year and a half. The eruption of 1822 continued with great violence 

 through more than 20 days ; that of 1834 twenty-four days ; that of 

 1850 nearly a month. True, the violence of an eruption is not 

 always to be measured by its duration, since moderate discharges of 

 vapour and scoriae, accompanying the emission of minor lava-streams, 

 have sometimes gone on for months together in the intervals be- 

 tween the more powerful eruptive paroxysms. In the present in- 

 stance indeed the vigour of the eruption seems to have been largely 

 out of proportion to its limited duration, although by no means 

 equalling in this respect some of those we have mentioned above, as 

 is well known to those who are acquainted with the admirable 

 volume of Professor Phillips. 



The cone of Vesixvius had been continually increasing both in 

 height and bulk since its truncation by the great eruption of 1822, 

 and in place of the deep and wide crater then formed, and repeatedly 

 filled up, and to some extent reformed, by subsequent eruptions of 

 minor violence, an upper cone had risen, giving a pointed apex to the 

 mountain. This subsidiary cone was in almost constant activity 

 throughout the year 1871, steam and scoriaB being continuously 

 ejected from its crater, while small streams of lava occasionally 

 flowed out of it, and found their way down to the northern foot of 

 the great cone, where they accumulated in or about the Atrio. This 

 state of moderately tranquil activity lasted through the first months 

 of this year, proving that up to that time the lava still occupied the 

 highest part of the chimney of the volcano in a state of more or less 

 fluid ebullition. 



Suddenly, on the morning of the 26th April, a violent earth-shock 

 was felt throughout the area of the mountain, and fearful detonations 

 and incessant rumbling noises, accompanied by other shocks, were 

 heard to proceed from the summit, which at the same time threw up 

 a lofty fountain of steam and stones. A paroxysmal eruption had 

 evidently commenced. The subterranean energy, residing in the 

 lower depths of the volcanic focus, had increased to a point at which 



