nce alternately a cessation and renewal of eruptions.

The first line of active vents which have been seen in eruption in the
Andes extends from lat. 43 degrees 28 minutes S.; or, from Yantales,
opposite the isle of Chiloe, to Coquimbo, in lat. 30 degrees S.; to
these thirteen degrees of latitude succeed more than eight degrees in
which no recent volcanic eruptions have been observed. We then come to
the volcanoes of Bolivia and Peru, reaching six degrees from S. to N.,
or from lat. 21 degrees S. to lat. 15 degrees S. Between the Peruvian
volcanoes and those of Quito, another space intervenes of no less than
fourteen degrees of latitude, said to be free from volcanic action so
far as yet known. The volcanoes of Quito then succeed, beginning about
100 geographical miles south of the equator, and continuing for about
130 miles north of the line, when there occurs another undisturbed
interval of more than six degrees of latitude, after which we arrive at
the volcanoes of Guatemala or Central America, north of the Isthmus of
Panama.[469]

Having thus traced out the line from south to north, I may first state,
in regard to the numerous vents of Chili, that the volcanoes of Yantales
and Osorno were in eruption during the great earthquake of 1835, at the
same moment that the land was shaken in Chiloe, and in some parts of the
Chilian coast permanently upheaved; whilst at Juan Fernandez, at the
distance of no less than 720 geographical miles from Yantales, an
eruption took place beneath the sea. Some of the volcanoes of Chili are
of great height, as that of Antuco, in lat. 37 degrees 40 minutes S.,
the summit of which is at least 16,000 feet above the sea. From the
flanks of this volcano, at a great height, immense currents of lava have
issued, one of which flowed in the year 1828. This event is said to be
an exception in the general rule; few volcanoes in the Andes, and none
of those in Quito, having been seen in modern times to pour out lava,
but having merely ejected vapor or scoriae.

Both the basaltic (or augitic) lavas, and those of the felspathic class,
occur in Chili and other parts of the Andes; but the volcanic rocks of
the felspathic family are said by Von Buch to be generally not trachyte,
but a rock which has been called andesite, or a mixture of augite and
albite. The last-mentioned mineral contains soda instead of the potash
found in common felspar.

The volcano of Rancagua, lat. 34 degrees 15 minutes S., is s