5 88 



NA TURE 



[April 19, 1906 



THE ERUPTION OF VESUVIUS. 

 HP HE eruption of Vesuvius has quieted down since 

 -*■ last week, though scoria? and ash continue to 

 be ejected and there still seems to be a slow flow ol 

 lava, but in comparison with the activity of the erup- 

 tion on April 8 the volcano is quiet — until next time. 

 How soon or how long deferred this may be cannot 

 be predicted, but the pause has enabled us to take 

 Stock of events and form some estimate of this out- 

 burst as compared with previous ones. The most 

 important qualification of earlier reports is in regard 

 to the reported flow of lava through the streets of 

 Ottajano ; an outburst of lava on the outer slope of 

 Monte Somma would be remarkable indeed, but later 

 accounts show that none such took place, the damage 

 at Ottajano and San Giuseppe being due to a very 

 heavy fall of ash. 



The reports from the Vesuvian Observatory and the 

 definite statement 61 Messrs. Thos. Cook and Son 

 that their electric tramway has not suffered more than 

 a temporary interruption of traffic, due to the fall of 

 ash, show that no lava flowed in that direction. On 

 the .other hand, there seems to have been an extensive 

 outflow into the Atrio del Cavallo and on the south 

 side of the volcano. The lava, which stopped just 

 short of Bosco-Trecase, seems to have reached further 

 than the stream of 1754. 



In spite of the prominence given to these lava 

 streams in the daily papers, the eruption seems to 

 have been less remarkable, in this respect, than thai 

 ol 1895, nol to mention others of earlier date, but the 

 volume of volcanic ash produced and scattered over 

 th ■ surrounding country has been very great, and 

 ih" aspect ol the volcano has been materially changed, 

 not only by the addition of a mantle of grey ashes, but 

 also by the destruction of a portion of the cone. The 

 upper part of the funicular railway has been destroyed 

 -blown away, so far as can be made out — in the 

 enlargement of the old crater; the volcano as a whole 

 C noticeably lower than it was, and must have re- 

 sumed very much the aspect it showed after the 

 eruption of 1822. 



The Naples correspondent of the Times described 

 in Tuesday's issue the nature and results of the recent 

 eruption. Some extracts from this narrative, dealing 

 with points of scientific interest, are subjoined, with a 

 diary of events abstrai ted from Tress reports. 



The most intense activity occurred on the night ol 

 Saturday. April 7, when the sides of the cone subsided 

 and the streams of lava, already set free, gained a terrible 

 impulse. The electric phenomena of thunder and lightning, 

 which ordinarily attend any great volcanic convulsion, were 

 then at their height, and the ejection of large blocks from 

 tin .r.ite,- and fiery scoriae is said to have surpassed any- 

 thing within the memory of the present generation. The 

 main courses taken by the lava flow seem to have been 

 six in number : towards Ottajano on the north, to San 

 Giuseppe and Terzigno on the east, past Bosco-Trecase to 

 Torre Annunziata on the south, to Torre del Greco and 

 past the observatory on the west. Of these, the most 

 formidable stream was that which descended towards Torre 

 Annunziata, those which deviated towards Torre del Greco 

 and Terzigno being only its branches. At Torre Annunziata 

 the lava stopped just short of the wall of the cemetery 

 outside the town. 



"I he actual area of ground covered by lava cannot yet 

 be conjectured, though it is believed to exceed that covered 

 by all recent eruptions. Next in importance comes the fall 

 of volcanic dust and scoria?. The direction of this fall varied 

 each day. The worst suffering was inflicted upon Ottajano 

 and San Giuseppe Vesuviano towards the north-east. In 

 both places a large number of houses succumbed to the 

 weight that fell on their roofs. Considerable damage was 

 also done, from the same cause, at Torre del Greco. 



NO. T903 VOL 73] 



During the first three or four days the dust plunged the 

 towns in the immediate vicinity of the volcano into utter 

 darkness, and materially increased the panic that had 

 already set in. Even Naples was in a state "I semi-dark- 

 ness, from which it had hardly emerged on April 12. The 

 roots and roads seem to l»- inches deep in an extraor- 

 dinarily line, reddish-grey dust, which rise, in den-, clouds 

 behind every carriage and foot passenger. 



In some places the drift of ash seems fully a yard deep: 

 at Ottajano and San Giuseppe in the lightest deposits it 

 iihi-i measure three inches. The gnat danger n both 

 places and, indeed, in most of the towns on the slopes 

 ol Vesuvius — would be a heavy rainfall and the formation 

 ol mud-torrents, which will more than complete the ruin 

 ilreadj begun by the lapilli. At the roast towns, Torre 

 del 1 in 1 0, lone Annunziata, Resina, and others, the work 

 of disencumbering the streets and buildings of tie- lapilli 



and ashes is already in active progress. 



It is difficult to compare the extent of this latest erup- 

 tion with that of those which have preceded it. Eye- 

 witnesses of both declare it to have been more formidable 

 than that of 1S72, which practically destroyed Torre del 

 1. nil, for the fourth time. The distance to which the ash 

 was carried is so dependent on other atmospheric influences 

 that it cannot constitute a test. In this case lb" ash seems 

 lo have reached Bari and towns on the Adriatic coast. 

 One notable change lias been wrought by the eruption. 

 Ilie cone, which has for so long been such a distinctive 

 feature ol the mountain, appears to be gone. 



I be following diary of the eruption is in continuation of 

 thai given last week : — 



April 11 Vesuvius Observatory. — Report from Dr. 

 Vlatteucci : — "Tor brevity's sake I do not give details of 

 m\ position and that of the carabineers at the observatory, 

 wiin h lias been very unpleasant and alarming. Throughout 

 the night and up to 8 o'clock this morning we were 

 completelv enveloped in dense showers of dust. As I 

 telegraph everything tends to reduce anxiety, and the 

 seismic instruments show quieter records than yesterday. 

 I shall remain here as long as possible — as long as I have 

 food. If my words could influence the population they 

 would be words of encouragement and sympathy in full 

 confidence that Vesuvius will shortly become calmer." 



Showers of volcanic ash and other fragmentary pro- 

 ducts continue to fall. San Giuseppe almost buried in 

 places lo mounds of ash and lapilli, and Ottajano in much 

 the same condition. Torre Annunziata remains abandoned, 

 and Torre del Greco is almost deserted. The roads in 

 Naples are covered with a thick layer of volcanic dust, 

 which continues to fall upon the city. The summit of the 

 \11I1. 010 cannot be seen on account of the dense clouds of 

 steam and dust over it, but it is reported that the shape 

 of tin run, has undergone great change, and Dr. 

 Matteucci estimates that the top is now nearly 250 metres 

 lower than before the eruption. 



1 pnl [2. — Seismographs quiet. Volcanic ash has ceased 

 to fall in Naples, Portici, Torre del Greco, and Torre 

 Annunziata, but the shower continues at Ponticelle, St. 

 An. 1st, isia and Somma. 



April 1;. No noticeable disturbances. The volcano siill 

 surmounted with a dense cloud, which appeared, however, 

 to be disapoearing. 



April 14. A shower of ash fell at San Giuseppe 

 Vesuviano and Ottajano to a depth of about \h inches. 

 Heavy falls of dust also recorded in the communes of 

 Collina, Strocchia, Boscoreale, Somma, and Ottajano. 

 Slight earthquake shock felt at Ottajano and Terzigno. 



Ipril 15. -At 2 p.m. a heavy shower of ash began fall- 

 ing at Ottajano, Boscoreale, Bosco-Trecase, ami Torre 

 del I, rii ii, causing intense darkness. There was a slight 

 tall of ashes at Portici, Resina, San Sebastiano, and San 

 Georgio. 



Ipril 10. -No signs ol activity. Seismographs quiet. 



April 17. — Conditions normal except for a shower of asb 

 falling mi Ottajano and St. Anastasia. Dr. Matteucci 

 reports from the observatory that, with the exception of a 

 few hour's, last night was calm. The activity of Vesuvius 

 is limited to a decreased emission of dust, falling in the 

 eastern districts. 



