ed Lucien.

"There; that enormous cone which rises to our right," I answered,
pointing in that direction.

"Is it the smallest of the three?"

"No; on the contrary, it does not measure less than 18,000 feet in
height. Dias Ordas, one of the captains of Fernando Cortez, made its
first ascent. Its name signifies 'smoking mountain.'"

"Yes; and I know that Istaccihuatl means 'white woman;' but I do not
know the height of it."

"It is 15,700 feet above the level of the sea."

"How can mountains like these be measured?" asked Lucien.

"In the first place, by geometrical calculations, and then, by the aid
of a barometer, when an ascent has been made. The column of mercury in
the instrument falls in proportion as the barometer is carried up the
mountain, because the air which presses upon the mercury reservoir
becomes less and less dense."

I quite forgot the lapse of time while contemplating the glorious
panorama spread beneath. Just around us the ground was rocky and
volcanic, and covered with mosses of various colors; rather lower down
the ground was hidden by the fallen leaves of giant trees; beyond was a
succession of smaller crests, frequently quite barren, sometimes covered
with sun-scorched verdure. On the horizon, which was hidden by a
transparent mist, the two volcanoes of the plateau stood out in bold
relief against the blue sky, facing the other colossus, which seemed to
protect us with its shadow. The peaks of these mountains, clad with
their perpetual snow, can be seen by sailors forty leagues at sea.

I was really sorry to give the signal for departure. We again met with
the pine-needles, and though our ascent was difficult and slow, our
descent was proportionably rapid. Thus we fell forward instead of
falling backward. Gringalet, who seemed amused at our ridiculous
postures, and was too confident in his own powers, shared our mishaps,
much to the amusement of his young master, who had predicted that such
would happen. L'Encuerado, utterly tired out, bethought himself of
dragging his basket along the ground, which was so thickly covered with
leaves that he managed it without damaging his load or breaking the
bottles.

At last we came upon oak vegetation; and, still farther down, tropical
plants. Various birds enlivened our journey by their song, while numbers
of brilliant-colored insects hummed cheerfully round us. In less than an
hour we had passed from autumn to spring, after having had a glimpse o