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THE NATIONAL GEOGRAPHIC MAGAZINE 



DRAINAGE CANAL AT ENTRANCE TO TUNNEL, VALLEY OF MEXICO 



Note the depth of excavation, which was started by peons carrying material on their 

 backs up the steep embankments by means of foot-holes. When this became unprofitable by 

 reason of depth, steam dredges and aerial carriers, using coal costing $10 per ton, were 

 utilized. The photograph shows peons carrying up the slope material for repair. The drain- 

 age system covers 50 miles, of which 30 miles are in excavated canal and 6 miles in tunnel. 



and numerous revolutions, has become 

 the Republic of Mexico of today. 



The battle of Lexington preceded by 

 14 years the establishment of a definite 

 government for the United States, with 

 an elective President ; and, although 

 Mexico reckons its independence from 

 1810, this was merely the date when the 

 priest Hidalgo struck the spark which 



started the patriotic flame resulting in 

 Spain being driven from power; for 12 

 years elapsed before Mexico's initial 

 home government was established with 

 Iturbide as Emperor. 



At that time Mexico claimed dominion 

 over an area exceeded only by those of 

 Russia and China, for it included Guate- 

 mala (subsequently separated), Texas, 



