VESUVIUS. 



" About dawn, the fummit of Vefuvius ceafed to be 

 Tifible : it was covered with a thick cloud, frequently fur- 

 rowed with lightning. This cloud gradually fpread itfelf, 

 and in a little time overfhadowed tlie gulf, the city of 

 Naples, and its vicinage. It was formed of a large quantity 

 of that fine fand called aflies, and prevented all fight of the 

 fire of the volcano. The fun, as it appeared above the 

 horizon, prefented a ftill more difmal pifture. From the 

 abundance of afhes in the air, it feemed more pale than 

 during the ftrongeft eclipfe ; and a black fcarf appeared to 

 be fpread over the whole of the gulf and the country. At 

 the extremity of the horizon, towards the weft, the day was 

 more clear, while the light at Naples was fainter than twi- 

 light ; and, with Pliny the younger, one might have faid, 

 *' Jam dies alibi illic nox omnibus nigrior denfiorque." 



" During this mournful night the air was perfeftly un- 

 agitated, and the fea calm : it was not difturbed even in the 

 flightefl degree, at leaft in the gulf of Naples. The flighteft 

 aftion of the volcano on it would have been perceptible at 

 the bafe of the mountain, and I was within a diftinft view 

 of this part of the fea ; but its influence on that element was 

 abfolutely null. 



" While one current of lava flowed over the weftern flank 

 of Vefuvius, fpreading ruin and defolation ; another fell 

 down its eaftern Hope, from an opening of inferior height, 

 and a greater diftance from the fummit. Tliis current was 

 not vifible at Naples : all that was perceived of it was a 

 great light in the atmofphere, produced by reflcftion from 

 the rolling fire. At firft it took an eaftern diredtion, turned 

 afterwards to the fouth, and defcended to the fpot called 

 Cognolo. There it fortunately found the valley of Sorienta, 

 65 feet wide, 121 deep, and 1627 long. This valley the 

 lava filled ; but as the volcano ftill continued to emit frefh 

 matter, the current afterwards fpread into the plain of 

 Forte, near to PozzeUe, where it divided into three 

 branches : one proceeded towards Bofco, another towards 

 Mauro, and the third to the plain of Mulara. The length 

 of this current of lava was not lefs than an Italian mile ; but 

 as it flowed conflantly over old lavas, it did but little harm, 

 merely laying wafte and occupying a fmall extent of vine- 

 yard. From the fpot where it diverged from its firft direc- 

 tion, it projefted a fmall branch in a continued line : falling 

 to this point over a very rapid iiope, the fpeed with which 

 it flowed muft have been confiderable ; and a portion of its 

 mafs preferving its firft impulfe, naturally fell in this fmall 

 ftream, in which were four' mouths in the fliape of an in- 

 verted cone, the bafe of which is in the furface of the lava. 

 This ftream terminates in a imall and regular hill of a conical 

 figure, on the fummit of which are two mouths in form of 

 inverted cones. The dimenfions of this fecond current are 

 nearly half thofe of the firft ; confequently the mafs of the 

 whole is adequate to 2,804,440 cubic fathoms. 



" The coincidence and perfeft refemblance of thefe two 

 currents of lava fufficiently prove that they had but one 

 common origin, and but one cauldron in which the matter 

 was fufed of which they wei-e compofed. How great 

 then muft that recipient be in which fuch an enormous 

 mafs could be contained ! And what powerful exertion of 

 ftrength muft have been required to break through the 

 mountain in fuch oppofite direftions ! The lava agitated by 

 the expanfion of elaftic fluids made its firft eff^orts to libe- 

 rate itfelf on the eaftern flank, and found a paflage ; but the 

 refiftance it met with from the mountain no doubt occafioned 

 its reflux or rebound againft its oppofite flank. 



" The weftern current, taking its departure from a more 

 elevated mouth, more quickly terminated its courfe ; but 

 the cauldron chiefly emptied itfelf by the eaftern opening. 



The lava iffued from it very flowly, compared with the 

 celerity with which that flowed which proceeded from the 

 eaftern mouth, becaufe it was no longer driven forward, or 

 comprefled by the total mafs, which was already greatly 

 diminiflied. 



" On the morning of the i6th, the lava ceafed to flow 

 over the weftern fide, and the mouth of the volcano began 

 to refume aAivity. The whole of its cone was covered with 

 a very thick rain of afties or powders, which totally hid it 

 from fight, fo that nothing could be diftinguiftied on Vefu- 

 vius, which was wholly inacceflible. In this ftate it con- 

 tinued four days, during which many fliocks of earth- 

 quakes were felt, and loud claps of thunder were heard. 

 Thunders raged in every part of the adjacent country, and 

 the flafties of lightning by which they were accompanied ■ 

 at intervals, for an inftant allowed a view of the mountain a 

 through the darknefs in which it was involved by the rain 

 of powders. This darknefs was fo prodigioufly great, that 

 at Caferto, and other places ten or twelve miles from 

 Vefuvius, it was impoflible to walk the ftreets at mid-day 

 without torches, and that circumftance v/as renewed which 

 is related by Pliny on the occalion of the eruption in the 

 time of Titus, " faces multae, variaque lumina folvebant 

 obfcuritatem." It is utterly impoflible to determine with 

 precifiou the quantity of afties or powders that fell in the 

 courfe of thefe days, as it was different in different places, 

 according to the direction of the wind ; it is, however, 

 computed, on the bafe of oblervations at different places, 

 that fourteen inches and fix lines in depth fell on an area, 

 the radius of which is three miles, the fummit of Vefuvius 

 being the centre." 



It would be erroneous to conclude, that all this mafs of 

 matter proceeded from the entrails of the mountain, the 

 greater part was the offspring of the ruins of the crater, 

 which during the three laft days fell into the abyfs. For, 

 after the rain of volcanic fand had ceafed, and the mountain 

 became vifible, its appearance excited much furprife, the 

 fummit had fallen, and its mouth was confiderably en- 

 larged. 



Inceflant rains followed this eruption, which continued 

 to the 3d of July. Whenever a cloud appeared above the 

 horizon, it feemed attracted by the volcar.o, and fcarcely 

 did it reach its fummit, ere immenfe ftreams were vifible, 

 precipitating themfelves with horrible roarings to the bafe 

 of the mountain. Thefe impetuous torrents of water, min- 

 gled with volcanic powders, overturned the bridges, har- 

 rowed up the roads, tore up the trees, and utterly devaf- 

 tated the fields of one of the moft rich and fiourifliing 

 countries in the world. Mephitic vapours were alfo exhaled, 

 which deftroyed all other vegetation, except the olive and 

 the pear-trees, which retained their verdure and ftrength. 

 It is remarkable, that during the whole of tliis eruption the 

 barometer at Naples was not fenfibly affected, and exhibited 

 no change, although the temperature and moifture of the 

 atmofphere experienced confiderable variation. 



Though the quantity of matter thrown out of Vefuvius, 

 during any fingle eruption, is not fo great as from ./Etna, 

 Vefuvius being of diminutive fize, compared with the latter 

 mountain ; yet the magnitude of fome of the ftones ejefted 

 is truly furprifing, and the quantity prodigious. Accord- 

 ing to fir William Hamilton, during the eruption of 1779, 

 the town of Ottacaiio, at the foot of Somma, was half 

 buried under the ftiowers of fand and fragments of volcanic 

 matter. A ftone, meafuring one hundred and eight feet in 

 circumference and feventeen feet in height, was thrown a 

 quarter of a mile clear of the mouth of the volcano. One 

 of ninety-two feet in circumference was tlirown much far- 

 ther. 



