clay. At first wood was used, but afterward masonry was deemed preferable. The water, however, gradually undermined the lateral walls, and deposited a large quantity of earth and gravel on the bottom of the canal. Martinez built small sluices at intervals to clear the passage, to obviate these difficulties. This remedy, however, proved insufficient, and the gallery was stopped up by the constant falling in of earth.
From 1608 to 1614 various schemes for enlarging the canal were discussed. In the latter year the court of Madrid, wearied out by the disputes of the engineers, sent out Adrian Boot, a Dutchman of large experience in hydraulic architecture. He was in favor of the Indian system, and advised the construction of great dikes and mounds of earth around the capital. He was unable to bring about the relinquishment of the Nochistongo Canal till 1623. About this time a new viceroy (Guelves) arrived, who scouted the idea that the City of Mexico was in danger of floods.
He had the temerity to order the Desague to be closed, and to make the water of the Lakes of Zumpango, and San Cristobal return to the Lake of Tezcuco, that he might see whether the peril was, in fact, as great as it had been represented. The last lake soon swelled rapidly, and the foolish directions to the engineer Martinez were countermanded.
The latter now began his operations anew, and continued them till June 20, 1629. Heavy rains fell, and suddenly the capital became inundated to the height of a metre (3¼ feet). Martinez was committed to prison. Contrary to every expectation, Mexico remained flooded for five years, from 1629 to 1634! During this interval four different projects were presented and discussed by the Marquis de Ceralvo, the viceroy. The misery of the lower classes was singularly increased while the inundation lasted. Trade was at a stand, many houses tumbled down, and others were rendered uninhabitable. The waters, however, in 1634, receded, the ground in the valley having opened on account of violent and very frequent earthquakes.
The viceroy now set the engineer Martinez at liberty. He was ordered to finish the desague, by enlarging the original tunnel. The Government levied particular imposts on the consumption of commodities for the expense of these hydraulic operations.
In 1637 the Viceroy Villena put the entire work in charge of Father Luis Flores, of the Order of St. Francis. It was decided to abandon the tunnel (socabon), to remove the top of the vault, and to make an immense cut through the mountain, of which the old subterranean passage was to be merely the water-course.
The monks of St. Francis continued to retain direction of this work for about forty years, when Martin del Soils, a lawyer, obtained from the court of Madrid the administration of the desague. He proved to be in-
