ORIZABA, POPOCATEPETL, IXTACCIHUATL, AND OTHER VOLCANOES OF MEXICO
While some of the volcanoes of Mexico are still in an active
condition, most of them are either only slightly active or are dormant
or extinct. Humboldt, the celebrated traveller and geographer, states
that there are only four active volcanic mountains in Mexico; namely,
Popocatepetl, Tuxtula, Colima, and Jorullo. But there are many others,
among which may be mentioned Orizaba, Ixtaccihuatl, Xinantecatl,
Tuxtula, Cofre de Perote, and Colima.
Of course, you can understand that, since extinct volcanoes may at any
time become active, in parts of the world where communication with the
interior is not good, many volcanic mountains that have been regarded
as extinct may have broken out temporarily, during historical times,
without their eruptions having been recorded.
It was at one time thought that Popocatepetl was the highest mountain
in North America. More recent measurements, however, have shown that
there are at least three other mountains in this part of the world,
that are much higher. One of these is the active volcano of Orizaba
that we will now briefly describe.
[Illustration: FIG. 16. MEXICO AND CENTRAL AMERICA]
Orizaba is situated in the north central part of Mexico, about
seventy-five miles west of Vera Cruz. Its ancient Aztec name was
Cittaltepetl, or _Star Mountain_. The height of the mountain is
18,200 feet. Like all high tropical mountains whose summits are
snow-clad, one would pass through the same changes in climate, in
going from its base to its summit, as in going along the earth's
surface from the equator to the poles. Near the base of the mountain
will be found a tropical climate, above that a temperate climate,
while in still higher regions, the climate of the Arctic region.
According to Russell, from whose work on the volcanoes of North
America much of the information concerning the volcanoes of Mexico
and Central America has been condensed, Orizaba has three craters on
its summit. The last recorded eruption took place about the middle of
the Eighteenth Century. The mountain is now in a dormant or extinct
condition, as may be seen from the fact that its three craters are for
the greater part filled with snow.
Orizaba, like Etna, and many other volcanoes, has deep fissures
extending through its sides. Through these, lava streams have flowed
during times when it was active. There are also found on the slopes
of this mountain many cones of a type known as _parasitic cones_.
These cones are not caused by materials that have been brought to the
surface during an eruption, but have been formed by the steam passing
through lava streams that have come out of the crater during other
eruptions.
Popocatepetl, or, as the word means, _The Smoking Mountain_, is the
second highest mountain in Mexico. According to recent measurements
made by the Mexican Government, its height is 17,876 feet.
Popocatepetl is situated on the edge of the great plateau of Mexico,
forty miles southeast of the City of Mexico. It is a conical mountain,
and is a magnificent object when seen from the City of Mexico, rising,
as it does, fully 10,000 feet from the elevation of the city, while on
the east it towers for nearly 18,000 feet above the level of the sea.
This splendid mountain is poetically described by Russell:
"Seen from the basal plains, it sweeps up in one grand
curve to nearly its full height,--a collossus of three and
a quarter miles in elevation, white with everlasting frost
on its summit, and bathed in the green of palms, bananas,
oranges, and mangoes, at its base. Evergreen oaks and
pines encircle its middle height, and above them, before
the ice itself is reached, occur broad areas of loose sand
into which the lavas have been changed by weathering. Soft
wreaths of sulphurous vapor may at times be seen curling
over the crest of the summit crater,--gentle reminders that
the days of volcanic activity are not yet necessarily over."
Popocatepetl takes its name, _The Smoking Mountain_ from the fact that
gases and vapor are continually being emitted from its summit crater.
It has a conical peak with a depression or crater on its summit.
The bottom of the crater is crossed by fissures from which small
quantities of steam escape, not, however, sufficient to melt all the
snow which covers the slopes of the mountain to a depth of from eight
to ten feet. A small lake of hot water has collected in the crater
from the water derived from the melting snow. This water, sinking
through the porous materials in the cone, is the source of a great
number of large hot springs that occur around the base of the mountain.
Reclus states that the first to climb to the top of Popocatepetl was
one of Cortez' officers, 1519.
Another snow-capped volcano, which rising from the plain of Mexico is
in clear view of the city, is Ixtaccihuatl (Ets-tak'-se-wat-el), or as
the word means in the ancient Aztec, _The White Woman_. This mountain,
as measured by Heilprin, is 16,960 feet in height. Ixtaccihuatl is
now in so dormant a condition that many who have climbed to the top
assert that it is not a volcano at all, since they find no crater on
its summit. Nor are there any signs of volcanic heat, the summit being
snow clad during summer. The conical form of the mountain, however,
and the fact that the entire mountain is formed of volcanic rocks,
show beyond doubt that it is an extinct volcano, whose crater has most
probably been completely filled in by the washing away of its sides.
Xinantecatl is another extinct volcanic mountain situated about forty
miles southwest of the City of Mexico. It is about 16,500 feet high.
Its name means in the ancient Aztec language, _The Naked Lord_. It is
also sometimes known as the Nevado de Toluca, or _The Snow of Toluca_.
On the top of the peak are two craters filled with lakes of fresh
water. Russell states that the larger of these lakes is about thirty
feet in depth and contain a peculiar species of fish.
Tuxtula is another volcano of Mexico, situated on the western coast
of the Gulf of Mexico, about eighty miles southeast of Vera Cruz. It
was an active volcano in 1664, when it threw out molten lava. It then
became dormant until March, 1793, when its long rest was broken by one
of the grandest explosive eruptions of modern times. This eruption
rivalled in energy the great explosive eruption which blew off the
summit of Coseguina, in Central America, in 1835. As is common in the
case of explosive eruptions, volcanic dust and scoriæ were blown high
into the air, and, being carried by the winds, fell on the roofs of
houses and on the land at a distance of 150 miles.
There have been a number of less violent eruptions of Tuxtula since
1835. Tuxtula is a comparatively low mountain, being only 4,960 feet
high, because much of the mountain was blown away by the eruption of
1793.
As Russell points out, it is not safe to infer that because an eroded
mountain is not lofty it cannot be young or energetic, since the very
energy of some of its eruptions may, as in the case of Tuxtula, blow
away a large part of the mountain. A low mountain, with an unusually
large crater, generally means a mountain that has been visited by a
great explosive eruption.
Another extinct volcano known as the Cofre de Perote is situated on
the eastern coast of Mexico, east of Ixtaccihuatl, about thirty miles
north of Orizaba. It takes its name Cofre de Perote which means the
Coffin of Perote, from its peculiar box-like shape. It was called in
the Aztec language "Nauhcampatepetl," or the _Four-Ridged Mountain_.
Cofre de Perote is in a dormant or extinct condition.
We will conclude this brief description of the volcanoes of Mexico
with the volcano of Colima, a mountain about 5,500 feet high situated
on the western coast of Mexico.
Colima has been active of recent years, eruptions having occurred in
1869, 1872, 1873, and 1885. During these eruptions lava escaped from
lateral openings in the sides of the mountain, these openings being
termed by the natives the _Sons of Colima_.