INTENDANCY OF PUEBLA. 317 



large the gallery ; but the operations were conducted 

 Avith very little energy, and in the end it was deter- 

 mined to" abandon the plan, to remove the top of the 

 vault, and to convert it into an open passage by cut- 

 ting through the hill. A lawyer, named Martm de 

 Solis, undertook the management of this enterprise ; 

 though it required nearly two centuries to complete 

 the work ; the canal not being opened in its whole 

 leno-th until 1789. As it now appears, it is stated by 

 Humboldt to be one of the most gigantic hydraulic 

 operations executed by man. Its length is 67,537 feet, 

 its o-reatest depth 197, and its greatest breadth 361 



The safety of the capital depends, 1st, On the 

 stone dikes, which prevent the water of the lake of 

 Zumpano-o from passing into that of San Chnstobal, 

 and the latter from flowing into the Tezcuco ; 2d, 

 On the dikes and sluices which prevent the lakes of 

 Chalco and Xochimilco from overflowing ; 3d, On 

 the o-reat cut of Enrico Martinez, by which the Rio 

 de Gliautitlan passes across the hills in the valley 

 of Tul? ; and, 4th, On the canals by which the Zum- 

 pano-o and San Christobal may be completely drained. 

 The1;e means, however expensive and numerous as 

 they must appear, are insuflicient to secure it against 

 inundations proceeding from the north and north- 

 west ; and our author asserts, that it Avill continue ex- 

 posed to great risks until a canal shall be directly 

 openedfrom the lake of Tezcuco. 



The intendancy of Mexico contains, besides the 

 capital, several towns of considerable size, of which 

 the more important are, Tezcuco, Acapulco, Tolucca, 

 and Queretaro, the latter having a population oi 

 thirty-five thousand. ■. . n 



2 The government of Puebla is wholly situated 

 in tiie torrid zone, and is bounded on the north-east 

 by that of Vera Cruz, on the south by the ocean, on 

 the east by the province of Oaxaca, and on the west 

 by that of Mexico. It is traversed by the cordille- 

 ras of Anahuac, and contains the highest mountain 



Dd3 



