U-eoiogy and Mineralogy. . £00 



II. Geology and Mineralogy. 



1. The Tenth International Geological Congress at Mexico 

 City. — The Congress began its sessions on Thursday, September 

 6, 1906, and adjourned on Friday, the 14th of the same month. 

 Previous to the opening meeting excursions were made, as fol- 

 lows : To the south for eight days to view the Archean and Ter- 

 tiary in the narrow canyon of the Tomellin on the way to Oaxaca, 

 the Lower Cretaceous in the mountains west of Tehuacan, and 

 the ancient ruins at Mitla. To the west for twelve days, two 

 excursions were given, — one to Jorullo to see the volcanoes 

 Toluca and Jorullo, and the other to the only active volcano in 

 Mexico, Colima, and the geysers. The best attended excursion 

 before the Congress was the one to the east for three days, to 

 see the deeply eroded Cretaceous at the edge of the high mesas 

 down which the railroads descend to the dissected Miocene level, 

 and then to the present ocean level at Vera Cruz. On the way 

 back to Mexico City a stop of a few hours was made at Orizaba 

 to view the symmetrical volcano of the same name and the 

 nearly vertical strata of the Middle Cretaceous. The most 

 extensive and varied excursion was the one for three weeks 

 immediately after the meetings of the Congress, to the north as 

 far as El Paso and east to Tampico. On alternate days, during 

 the sessions of the Congress, excursions were given to Cuerna- 

 vaca, to San Juan Teotihuacan to examine the work of restoring 

 the great pyramids of the Sun and Moon, and to the Pachuca 

 silver mines. These excursions were of great profit to all, while 

 the hospitality received en route was lavish. 



The opening session of the Congress was held on the morning 

 of September 6, at eleven o'clock, in the Salon de Actos of the 

 School of Mines, in the presence of the President of Mexico, his 

 cabinet, his personal and official staff, and the ministers of foreign 

 countries. A short opening address was given by Sr. Luis 

 Salazer, Director of the School of Mines. The address of wel- 

 come was read by the Subsecretary of Fomento and the Hono- 

 rary President of the Congress, Sr. Andres Aldasoro. The 

 retiring President of the Congress, Prof. Emilio Tietze, made a 

 very pleasing address, and was followed by the President-elect, 

 Sr. Jose G. Aguilera, Director of the National Geological Insti- 

 tute of Mexico. The Secretary-elect, Sr. E. Ordonez, outlined 

 the work of the sessions. The President of the Republic then 

 pronounced the Congress opened. The succeeding meetings were 

 held in the Geological Institute, a building just completed and 

 containing accommodations for the excellent equipment, collec- 

 tions, library, and staff of the Mexican Geological Survey. 



The following are the officers of the present Congress, who 

 either in 1909 or 1910 will turn over the machinery of the Tenth 

 Conofress to the Eleventh, to be held at Stockholm : ■ 



