26 Hobbs.—Notes on a Trip to the Lipari Islands. 
The island on which the volcano is located, which bears the same 
name — Volcano or Vnlcano, has an area of about eight and one-half 
square miles. The crater, the “ Gran Cratere ” of the natives, is situated a 
little to the northward of the center of the island. On a peninsula at 
the north end of the island is Vulcanello, a small triple-cratered hill 
joined to the mass of the island by a low and narrow neck of land. This 
forms two bays, of which the one on the east side is called the Porto di 
Levante, and is the landing place for boats. The present mountain is a 
cinder-cone par excellence , and rises a few hundred yards south of the 
landing. The crater had a diameter according to Johnston-Lavis (in 
September, 1889) of about 250 metres and a depth of 30-40 meters below 
the lowest lip. (Scottish Geographical Magazine, VI., p. 147.) These 
values are much lower than those of Baltzer taken in 1873, who gives 
the diameter of the crater as 900 metres. The depth of the crater he 
measured and found to be 86 metres (Zeitsch. d. d. geol. Gesellschaft, 1875, 
p. 9). The height of the lip of the crater (the Piano della Fossa ) is about 
700 feet above the sea. With the exception of a moderate-sized obsidian 
stream on the northwest flank, the material of the cone seems to be en¬ 
tirely fragmentary. Baltzer, in 1873, sketched beds showing the dip of the 
material within the lip of the crater to be toward the center. Near the ob¬ 
sidian stream, just outside the crater rim on the north side, is a secondary 
crater about 200 feet in diameter which has long been an active fumarole. 
Encircling the present crater at a distance of one-half to three-quarters 
of a mile is an older explosive crater, the highest point of which is Mte. 
Saraceno to the south. To the south of this Judd has described three 
still older craters, the centers of which lie in the medial line of the 
island. All these older craters including that of Monte Saraceno, unlike 
the present active one, are essentially composite in character being 
made up of lavas with ash, lapilli, etc.. The lavas near the south of the 
island are doleritic in character, rich in olivine, while to the north they 
are composed of trachytic rock. The beds are traversed by radial dikes 
showing the former existence of parasitic cones. Some of these dikes 
belong to the curiously hollow type recently described by Johnston- 
Lavis from Vesuvius, Stromboli and this locality. (“L’Eruzione del 
Vesuvio nel 2 Maggio, 1885,” Ann. d. Accad. O. Costa d’Asp. Naturalisti, 
Era 3, Vol. 1. Nature xxxviii, 13.) These are due to the draining out of 
the lava below after it has been injected into the fissure and a portion 
has consolidated on the walls. 
The structure of the island shows clearly that the early eruptions 
which built it up were largely of basic lava, that the active vent was 
migratory northward along the medial line of the present island, each 
successive eruption blowing out the north wall of the crater formed by 
the preceding eruption and affording more and more acid material. Ac¬ 
cording to Scrope the present form of the volcano is.largely due to the 
