e had ocular evidence of the advantages of artificial
irrigation, they even neglected to keep in repair the water-channels on
their own ground. Now the traveller, riding through Southern Spain, may
see in desolate barren valleys remains of the Moorish works which
centimes ago brought fertility to grain-fields and orchards, and made
the country the garden of Europe.

There was another nation who seem to have far surpassed both Moors and
Aztecs in the magnitude of their engineering-works for this purpose.
The Peruvians cut through mountains, filled up valleys, and carried
whole rivers away in artificial channels to irrigate their thirsty
soil. The historians' accounts of these water-works as they were, and
even travellers' descriptions of the ruins that still remain, fill us
with astonishment. It seems almost like some strange fatality that this
nation too should have been conquered by the same race, the ruin of its
great national works following immediately upon the Conquest.

Spain is rising again after long centuries of degradation, and is
developing energies and resources which seem likely to raise it high
among European nations, and the Spaniards are beginning to hold their
own again among the peoples of Europe. But they have had to pay dearly
for the errors of their ancestors in the great days of Charles the
Fifth.

The ancient Mexicans were not, it is true, to be compared with the
Spanish Arabs or the Peruvians in their knowledge of agriculture and
the art of irrigation; but both history and the remains still to be
found in the country prove that in the more densely populated parts of
the plains they had made considerable progress. The ruined aqueduct of
Tetzcotzinco which I have just mentioned was a grand work, serving to
supply the great gardens of Nezahualcoyotl, which covered a large space
of ground and excited the admiration of the Conquerors, who soon
destroyed them, it is said, in order that they might not remain to
remind the conquered inhabitants of their days of heathendom.

Such works as these seem, however, not to have extended over
whole provinces as they did in Spain. In the thinly peopled
mountain-districts, the Indians broke up their little patches of ground
with a hoe, and watered them from earthen jars, as indeed they do to
this day.

The Spaniards improved the agriculture of the country by introducing
European grain, and fruit-trees, and by bringing the old Roman plough,
which is used to th