PROCEEDINGS OF THE ROCHESTER ACADEMY OF SCIENCE 

 Vol. 4, pp. 67-74, Plates 2-5. June 24, 1902. 



BACUBIRITO OPic 



OR 



OAPD' J, , 



The Great Meteorite of Sinaloa, Mexico. 

 By Henry A. Ward. 



For more than a century the meteorites of Mexico have attracted 

 attention and record. In his great work on La Nouvelle Espagne, 

 pubHshed in 181 1, Humboldt described in a broad and philosophical 

 way the great field of the Toluca Irons and the size of some isolated 

 masses in the States of Zacetecas and Durango. From that day until 

 this, naturalists and travellers in Mexico have examined and described 

 this product of the country, commenting particularly upon their fre- 

 quence and their size. 



Their frequence has been greatly overestimated. The total number 

 credited to the Republic in Castillo's full catalogue, published in 18S9, 

 was twenty-seven. At the present day there are known thirty-two dis- 

 tinct localities, omitting the numerous points embraced in the distribu- 

 tion of the masses in two or three wide-spread showers. Leaving out 

 one or two extra-limital localities, the Mexican falls have all been in a 

 belt some 1000 miles in length, reaching from the 30th parallel of north 

 latitude, south to the 17th parallel, and with an average breadth of 

 about 280 miles. This belt of meteoric falls follows largely the 

 central axis of the greal Mexican Plateau, reaching from the United 

 States frontier-line obliquely south and east through the Republic to 

 near the Pacific. In this tapering, truncated triangle, which encloses 

 about 280,000 square miles, there occur thirty well distinguished 

 meteorite falls. Comparison with other parts of the world shows that the 

 relative number of Mexican meteorites is much less than seems to be 

 generally supposed. Turning to the United States we measure a like 

 area, though of a somewhat different form, with its major axis east and 

 west, and enclosing the six continuous states of Kansas, Missouri, 

 Kentucky, Tennessee, North Carolina and South Carolina. This area 



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