was discovered in the State of Coahuila. American, French, English, and Mexican capitalists combined to form the Compañía Carbonifera Agujita e Annexas which developed large mines at Agujita and Lampacitos which furnished the railroads with an abundant supply of much cheaper fuel than they had ever had before, and also rendered possible the building of large smelters, the development of iron mines, the establishment of iron and steel production, and other important industries.
These alien coal barons were not long permitted to continue their crime of enabling many thousands of Mexicans to earn a far better livelihood than they had ever enjoyed before cheap fuel became known. One of the first acts of Carranza after his revolution was anounced in the "Plan of Guadalupe," on March 26, 1913, was to send his brother, Jesús Carranza, on May 26 to call these coal producers to account. Perhaps the story of what followed cannot be better told than in the words of an American who was interested in the works. Here is what he wrote: