J. W. Judd—On Volcanos. 209 



in the least resemble the report of a cannon, but rather the rushing 

 sound which is heard when a large number of rockets are discharged 

 simultaneously. The noise of the falling fragments, falling upon 

 and rattling down the sides of the crater and the Sciarra a few 

 seconds after, was quite as striking as that of the explosion itself. 



After watching the explosions for a considerable period, both on 

 this and several other occasions, I found myself quite unable to 

 correlate, in any way, the force and duration of the explosions with 

 the intervals between them. I feel strongly led towards the conclu- 

 sion that there were at least two orifices within the crater discharging 

 independently. On several occasions two explosions were so close 

 to one another, that I can hardly believe they took place from the 

 same mouth. The observations of MM. Abich, de Quatrefages and 

 Deville lend great support to this supposition. 



I was informed by very intelligent residents in the island, 

 namely the priest and his brother, whom I closely questioned upon 

 the subject, that the most striking variations occur in the condition 

 of the volcano. Sometimes, in summer, intervals of considerable 

 length, occasionally extending to two hours, were declared to pass 

 without any explosion. During the winter, however, it was said 

 very violent outbursts sometimes take place. Large stones fall in 

 the cultivated and inhabited portions of the island (and some of 

 these I was shown) ; streams of lava flow down the Sciarra into the 

 sea ; and dead fish in great numbers are found floating around the 

 island. 



The succession of explosions which I witnessed on different 

 occasions may thus be represented, using M for an outburst of 

 moderate intensity, v for a violent, and V for an excessively 

 violent one ; s stands for slight, and S for very slight explosions. 

 The intervals between them are given in minutes : — 



On the 18th of April, 1874, commencing at 743 a.m. 



M 61 — M 4f ,— v 16,— M 4,— v 11 — s 21 — s 2f— S 5£,— V 6f, 

 v 3f ,— M 7f ,— v 11 — S 4,— M 9— s i — s 21 — M 3,— M If — s 21 

 S 4— M f ,— M 51— M 4.— s If,— S f — M 1,— S 5£,— M 31 — 

 s 101— M 5 _ v 5 _m ii _ v 181 —V 21— M 21— M 8|,— V 5, 

 M 5i — s 21— S 61 — S li — s 11— S 61 —v 3f— M 31,-s 1|, — 

 S 8— s i — S 2— s 2J,— s 6,— M 3— s 4— v If ,— s 51 — Y. 



On the 24th of April, 1874, beginning at 4'56 a.m. 



V 101-s 51— s If,— v. 



On the 25th of April, beginning at 7-8 p.m. 



v 30— s 1,— V 31— v 2— S 1— s i— v 31 — M 21 — M 41 — 

 M 2— M li -S 1— v 11 — M 81— Y 2f— S 41 — s 2,— v 21 — 

 s i — M 2,— Y 5,— s 3— M li, — Y 3,— M 6,— Y 10,— M li — M 5, 

 — Y 1\ ,— s 31 — M 3,— S3J. 



Having thus given a resume of the observations which have 

 been made on the very interesting volcano of Stromboli during 

 more than a hundred years, we may proceed to summarize those facts 

 concerning its general features, and the nature of the operations 

 going on within it, which these observations combine to establish. 



With respect to the heights of the various parts of the mountain, the 



DECADE II. — VOL. II. NO. V. 14 



