the top. One of the Spaniards,
Diego Ordaz, tried to climb to the summit, and got as far as the snow;
whereupon he returned, and got permission to put a burning mountain in
his coat of arms, in commemoration of the exploit! If, as he declared,
a high wind was blowing, and showers of ashes falling, his turning back
was excusable, though his bragging was not. He seems to have afterwards
told Bernal Diaz that he got to the top, which we know, by Cortes'
letters to Spain, was not true. A few years later, Francesco Montano
went up, and was lowered into the crater to get sulphur. When Humboldt
relates the story, in his _New Spain_, he seems incredulous about this;
but since the _Essai Politique_ was written the same thing has been
regularly done by the Indians, as the merest matter of business, until
the crater has been fairly worked out.

We took our last look at Mexico from the ridge of the crater, and,
descending twenty feet at a stride, soon reached the bottom of the
cone. As far as we could see, the substance of the hill seemed to be of
basaltic lava, which was mostly covered with the _lapilli_ which I have
spoken of before as ashes and volcanic sand. Even before we reached the
pine-forest there was evidence of the action of water, which had
covered the slope of the mountain with beds of thick compact tufa,
composed of these lapilli mixed with fragments of lava. The
water-courses had cut deep channels through these beds, and down into
the rock below; so that the streams from the melted snow rushed down
between walls of lava, in which traces of columnar structure were
observable.

The snow we had travelled over was sometimes dry and powdery, and
sometimes hard and compact. There were no glaciers, and no glacier-ice,
properly so called. It never rains at this elevation; and, though
evaporation goes on rapidly with half the pressure taken off the air,
and a great increase in the intensity of the sun's rays, the snow
either passes directly into vapour, or carries the water off
instantaneously, as it is formed. Only so much water seems to be
produced and re-frozen as suffices to make the snow hard, and in some
favourable places near the rocks to form lumps of ice, and some of
those great icicles which the Spaniards brought down from the mountain
on their first expedition, so greatly astonishing their companions.

When we reached the rancho we thought of passing another night there;
but the Indians who had gone down to the