468 



rallel of the town of Mexico, between Toluca, 

 Xalapa, and Cordoba, its maximum of height ; 

 there, several colossal summits rise to 2400 and 

 2770 toises. Farther north, the chain called 

 Sierra Madre * runs N. 40° W. towards San 

 Miguel el Grande and Guanaxuato. Near the 

 latter town (lat. 21° 0' 15"), where the richest 

 silver mines of the known world are found, it 

 takes an extraordinary breadth, and is divided 

 into three branches. The most eastern advances 

 towards Charcas and the Real de Catorce, and 

 lowers progressively (turning to theN.E.) in the 

 ancient kingdom of Leon, in the province of Co- 

 hahuila and Texas, That branch stretches from 

 the Rio Colorado de Texas, crossing the Arkansas, 

 (on the west of Arkopolis) towards the confluence 

 of the Mississipi and the Missouri (lat. 38° 51'). 

 It bears the name in those countries of the 

 Mountains of Ozark -f*, and attains 300 toises of 

 height. An excellent observer, Mr. Edwin 

 James, believes that on the east of the Missis- 

 sipi (lat. 44°— 46°), the Wisconsan Hills which 



* In the north-east part of the ancient intendance of 

 Mexico, between Zimapan, El Doctor and Ixmicuilpan. 



f Ozark is at once the ancient name of Arkansas, and of 

 the tribe of the Quawpaws Indians, who inhabit the banks of 

 that great river. The culminant point of the Mountains of 

 Ozark is in 374° of latitude, between the sources of the 

 White and Osage rivers. (Long. Expedition to the Rocky 

 Mount., 1823, Vol. ii, p. 80, 409, 423.) 



