e is a spacious swimming-bath
within the walls, beside the single bathrooms, in both of which the
water is kept at a delightful temperature. The luxury of these baths,
after a long, dusty ride over Mexican roads, can hardly be imagined by
those who have not enjoyed it. In the vicinity of the Plaza Mayor,
ice-cream was hawked and sold by itinerant venders. We were told of a
mysterious method of producing ice, which is employed here during the
night, by means of putting water in the hollowed stalk of the maguey or
agave plant, but we do not clearly understand the process. The volatile
oil of the century plant is said to evaporate so rapidly as to freeze
the water deposited in it. At any rate, the natives have some process by
which they produce ice in this tropical clime; but whether it is by aid
of the maguey plant, from which comes the pulque, or by some other
means, we cannot say authoritatively. In the cities and on the Texan
border, ice is largely manufactured by chemical process aided by
machinery, a means of supply well known in all countries where natural
ice is not formed by continued low temperature.

San Luis Potosi is situated about one hundred miles to the eastward of
Aguas Calientes, on the branch road connecting the main trunk of the
Mexican Central with Tampico on the Gulf. It is the capital of the State
of San Luis Potosi, and has, according to estimate, over forty thousand
inhabitants. The city contains many fine buildings, the most notable
among them being the state capitol, the business exchange, the state
museum, the mint, and the public library. This last-named contains
between seventy and eighty thousand volumes. There is here a larger
proportion of two-story buildings than is seen in either Saltillo or
Monterey. There are also a college, a hospital, and a theatre. It has
several plazas and many churches. The cathedral is quite modern, having
been erected within the last forty years; it faces the Plaza Mayor,
where there is a bronze statue of the patriot Hidalgo. We are here fully
six thousand feet above the sea level, in a wholesome locality, which,
it is claimed, possesses the most equable climate in Mexico, the
temperature never reaching freezing-point, and rarely being
uncomfortably warm. There are several fine old churches in San Luis
Potosi, containing some admirable oil paintings by Vallejo, Tresguerras,
and others of less fame. The city is three hundred and sixty miles north
of the national c