August 28, 1908] 



SCIENCE 



285 



magma to tlie edge of the said depression," 

 (D). May: In this month occurred the great 

 event of the year — the lava outhurst which 

 initiated the long period of lava emission 

 culminating in the catastrophal eruption of 

 April, 1906. Mercalli writes: "In the night 

 of the 25th-26th, after the strongest explosions, 

 the entire surface of the terminal conelet was 

 aglow. The maximum occurred on the 26th: 

 by day I saw columns of white vapors without 

 ashes which rose to a thousand meters above 

 the crater; at 5 p.m., although yet day, already 

 there commenced to appear the incandescence 

 of the projected magma : later the ejected 

 scorisa formed streaks of fire on the external 

 flanks of the cone. At 8 :30 p.m. a strong ex- 

 plosion commenced with a very vivid white 

 light, certainly due to flames; there followed 

 after a few seconds the usual red color of the 

 bits of incandescent magma. . . . During the 

 day of the 27th the explosions and trembling 

 of the ground were noticed as far as the Hotel 

 Eremo. At about 5 :30 p.m. the custodians of 

 the upper station of the funicular railway 

 felt strong earth-shocks. A little later, viz., 

 at 6 :15, there opened a first mouth of out- 

 flow," etc., {E). June: "About the 24th the 

 increase of the outflow was accompanied by a 

 strong explosive activity of the mouth where 

 there was formed a conelet of scorise projected 

 from a large eruptive fumarole, (driblet-cone 

 of the English). . . . During the 23d and 

 24th the explosions were strong but mixed : in 

 the evening they began with dark jets to 

 which quickly succeeded the projection of in- 

 candescent scoriffi. On the 25th the explosive 

 activity was very strong until evening (about 

 Y p.m.) when a portion of the interclosed 

 terminal conelet collapsed," {F). July: 

 " Often the lava flowed for a considerable dis- 

 tance covered by preceding lavas, then welled 

 up again from ' pseudo-mouths.' Eapid 

 changes succeeded from the breaking and 

 perhaps the re-fusing of the lava crust at the 

 times of increase. For example, in the early 

 evening of the 29th the principal stream 

 flowed for the most part covered; while 

 instead, a few hours later (between 9 and 12 

 p.m.), I saw the stream all continuous and 



very vivid, especially in the lower part," (G). 

 August : " The maximum occurred on the 8th : 

 then the projectiles reached the edge of the 

 crater of 1872 and the windows and doors of 

 the lower funicular station were rattling," 

 (ZT). September: "The morning of the 8th, 

 between four and five o'clock (the lava) 

 crossed the roadbed of the railway, covering it 

 for about 120 meters, after having demolished 

 in part the large stone wall which the firm of 

 Cook had constructed to protect the lower 

 station of the funicular," (Z). October: The 

 activity was generally great throughout the 

 month, but I think the culmination is indi- 

 cated by these words : " After 3 a.m. of the 

 28th-29th, very violent explosions commenced 

 which shook the two stations, upper and lower, 

 of the funicular." The station master wrote 

 me : " After 3 a.m. a formidable first shock 

 opened up a series of shocks which seemed as 

 though each would dislocate the entire funic- 

 ular," (J). November: . . . "Slight in- 

 creases (in the lava flow) occurred on the 

 morning of the 6th (K) and on the 11th, 

 17th and 26th (L) {M) (N) . . . the ex- 

 plosions became rather strong on the 5th and 

 6th," (Z). December: "After the 16th, a 

 second, more central mouth gave mixed or 

 vulcanian explosions : from the 16th to the 

 21st and especially on the evening of the 17th a 

 considerable quantity of ash rained as far as 

 the lower station of the funicular. All the 

 while the strombolian action of the other 

 mouth continued," (0). In a summing up for 

 the year Mercalli states : " The elevation of the 

 magma to the edge of the crater (19th-20th 

 April) and the explosions accompanied by 

 flames (26th of May) signal the two most im- 

 portant maxima of the strombolian dynam- 

 ism," (D and E). "In coincidence with the 

 second strombolian maximum there was insti- 

 tuted a sub-terminal outflow of lava," (E). 



Mention should also be made of the great 

 Calabrian earthquakes on September 8 (Z) 

 and on October 30 (J), and of a volcanic 

 earthquake at Naples on November 26 (N). 



Mercalli's " Notizie Vesuviane " for 1906 

 are not yet published. The activity was very 

 great during the first months of the year, with 



