288 



JOURNEY TO MEXICO. 



IClevated 

 plains. 



Mesica 



Ancient 

 mincb. 



CiL\P. XXIII. pansingo, Tehuilotepcc, and Tasco, which are situated at 

 a height varying from 3500 to 5900 feet above the st;.!, 

 they entered a region blessed with a temperate climate, 

 and producing oaks, cypresses, pines, tree-ferns, and the 

 cultivated cereal plants of Europe. After visiting the 

 silver-mines of Tasco, the oldest and formerly the richest 

 of Mexico, they went up by Cuernavaca and Guachilaco 

 to tlie capital. Here they spent some time in the 

 agreeable occupation of examining numerous curiosities, 

 antiquities, and institutions, in making astronomical 

 observations, in studying the natural productions of the 

 surrounding country, and in enjoying the society of en- 

 lightened individuals. The longitude of Mexico, which 

 had been misplaced two degrees on the latest maps, was 

 accurately determined by a long series of observations. 



Our travellers next visited the celebrated mines of 

 Moran and Real del Monte, and examined the obsidians 

 of Oyamel, which form layers in pearlstone and porphyry, 

 and were employed by the ancient Mexicans for the 

 manufacture of knives. The cascade of Regla, a repre- 

 sentation of which forms the vignette to the present 

 volume, is situated in the neighbourhood. The regularity 

 of the basaltic columns is as remarkable as that of the 

 deposites of Staff^i. Most of tliem are perpendicular, 

 though some are horizontal, and others have various 

 degrees of inclination. They rest upon a bed of clay, 

 beneath which basalt again occurs. Returning from 

 this excursion in July 1803, they made another to the 

 northern part of the kingdom, in the course of which 

 they inspected the aperture made in the mountain of 

 Suicog for the purpose of draining the valley of Mexico. 

 They next passed by Queretaro, Salamanca, and the 

 fertile plains of Yrapuato, on tlie way to Guanaxuato, 

 a large city placed in a narrow defile, and celebrated for 

 its mines. 

 Abode at There they remained two months, making researches 



Guana-xuatc into the geology and botany of the neighbouring country. 

 From thence they proceeded by the valley of San Jago 

 to Valludolid, the capital of the ancient kingdom of 



