llowed to become filled with water.
These conditions, coupled with the low price of silver for many years,
have caused the population of the city to dwindle until now there are
scarcely more than ten thousand inhabitants and very many of the
buildings are in ruins. These mines have produced twenty-seven thousand
tons of silver since their discovery, and at the present day many of
them are yielding large returns.

The Bolivian plateau is one vast mineral bed abounding in rich mines of
copper, tin, silver, and gold. In Bolivia alone there are upward of two
thousand silver mines; while some of the richest tin mines in the world
are found here. Lodes of pure tin several feet in width have been
followed down six hundred feet. Tin mines were recently discovered among
the mountains thirteen thousand five hundred feet above the level of
the sea, near the shores of Lake Titicaca.

Two railroads now reach this high plateau, one from the seaport town of
Antofagasta, Chile, to Oruro, Bolivia; the other from Molendo, Peru, to
Puno, on Lake Titicaca. The most wonderful railroad in the world and the
most costly in its construction, the Oroya Railroad is about one hundred
fifty miles long. It begins at Callao, Peru, and ends at Oroya. The
highest point reached by it in crossing the Andes is fifteen thousand
six hundred and sixty-five feet. It is said that seven thousand lives
were lost in its construction. Much of the road-bed was blasted through
solid rock on the sides of the mountains. The cost of construction was
about three hundred thousand dollars per mile. It has seventy-eight
tunnels, the longest being the Gallera tunnel, which pierces Mount
Meiggs at the altitude of fifteen thousand six hundred and sixty-five
feet. This is the highest place in the world where steam is used as a
motive power. Ultimately the road is to be extended to the celebrated
mines of Cerro de Pasco, fifty-one miles beyond its present terminus,
Oroya.

The chief business of these railroads extending into the Andes is
carrying ore, bullion, and wool. Their construction marks the acme of
engineering skill; the scenery along them surpasses that of all other
regions in its wild ruggedness, grandeur, and sublimity.

In ascending to such great heights quickly one not accustomed to high
elevations is apt to experience dizziness, headache, and nausea. At
first even the effort to talk on reaching these lofty places by train is
laborious. Dogs taken from the lowl