8 B. Hobson— Mexican Volcanoes. 
there a Ficus had entwined its stem with that of a palm, and orchids 
grew among the branches. We passed the Hacienda La Playa, and 
descended to the bottom of the natural amphitheatre in which Jorullo 
lies.' Giant trees dropped their adventitious roots to the ground, 
climbing plants entwined their trunks, exquisite natural ferneries 
were on every hand, but what most delighted us was the abundance 
of streams and the greenness of the luxuriant tropical vegetation. At 
5.15 p.m., after 15 miles ride from Rancho Nuevo, we reached the 
comfortable house at Mata de Platano, south-east of Jorullo, which 
the copper-mining Compania de Inguaran had placed at our disposition. 
At last we had arrived at the goal of our journey, the historic 
volcano, which first appeared in September, 1759, and was visited in 
1803 by Alexander von Humboldt, whose description? has made it 
classic ground for the geologist. 
Jorullo. 
As already mentioned, Jorullo lies at the bottom of a great natural 
amphitheatre, 8$ miles in diameter, formed by erosion in the Central 
Plateau, and with its concavity facing south. Within this amphi- 
theatre the volcano stands upon a raised platform or minor plateau 
of old basaltic lavas, named the Mesa de la Higuera, the surface of 
which is inclined towards the south and west. On every side stand 
older basaltic cones, such as the Cerro Blanco, 14 miles to the south, 
Cerro del Bonete, 1 mile to the east, Cerro del Saucito, 14 miles 
north-east, Cerro de la Cruz, 2} miles north-west, Cerro del Veladero, 
23 miles west. Looking northward from the Pico de Humboldt, the 
north-eastern summit of Jorullo crater rim, one sees the escarpment 
of the great plateau rising over 3,000 feet above the floor of the 
amphitheatre and densely wooded; the western side of the amphi- 
theatre is formed by the dioritic chain of Las Canoas, the eastern by 
the chain of Inguaran, while towards the south rise range after range 
of mountains until in the far distance the great Sierra Madre del Sur 
closes the view. Only immediately to the west of the cone is there 
a comparatively level space of 3} square miles covered by the lava- 
flows of Jorullo. Rising from the plateau of Higuera, and ranged in 
a line running from N. 35° E. to 8. 85° W. true, stand four cones, not 
six as older observers reported. These are the vents of Jorullo, though 
only the largest of the four is properly so called, the other minor (not 
parasitic) cones being termed ‘ voleancitos’ or small volcanoes. 
The Chief Cone. 
Although the highest part of the cone (termed by Ordonez Pico de 
Riano) reaches 4,330 feet above sea-level, Jorulio is not imposing 
from its size, for even on the west side it only rises 1,312 feet, and on 
the east side only 574 feet aboveits base. It is hardly an exaggeration 
to say that there are scores of nameless voleanoes in Mexico of equal 
size, though not of equal interest. 
1 Humboldt mentions guavas (Psidiwm pyriferum), a fan-palm (Corypha pumos) 
now called Coper: ‘nicia pumos, and an alder (Alnus Jor Mises at the Playas de Jorullo. 
2 ««Kosmos’’: J. G. Cotta’sche Verlag, Stuttgart, vol. iv (1558), pp. 334-348, 
and English translation by Otté & Dallas, “Bohn’s ‘Library, 1865, vol. v, pp. 808-328. 
