in New York by the American Bank Note Company and were professionally engraved on steel plates, with intricate machine turned designs like those on paper currency. In design and execution, this "Bank Note" issue closely resembles contemporary stamps manufactured by United States bank note companies for other Latin American countries such as Argentina and Brazil as well as the United States. Late in 1877, the printing plates were sent to Mexico City, and thereafter the stamps were printed in Mexico. There are a great number of varieties of this issue with differences in the overprints and type of paper and watermarks. In 1879, Mexico joined the Universal Postal Union which required standard rates for international mail, that were actually lower than Mexico's domestic rates. Mexico accordingly released a new issue depicting Juárez for exclusive use on international mail. District overprints continued through 1883 after which they were no longer required. In 1895, Mexico issued a series of stamps depicting various methods of delivering mail, including a letter carrier, a mail coach and a mail train. Philatelists call this the "Mulitas" issue (little mules), after the 4 and 12 centavos stamps depicting a mule carrying a pack of mail followed by a mailman on horse. This issue has a great number of variants, including different perforations and watermarks, and is assigned 50 major (and many minor) catalog numbers in Scott. Twentieth century Early twentieth century In 1899, Mexico issued a definitive series depicting the Mexican coat of arms with the eagle and snake for the lower values and images of Mexican landmarks such as the National cathedral for the higher values. The authorities had been dissatisfied with the quality of the locally produced Mulitas issue, and had this finely engraved issue manufactured by Bradbury Wilkinson and Company in London. This was followed in 1910 with an issue commemorating Mexico's centenary of independence and depicting important Mexican patriots and historical events such as the Declaration of Independence. Mexican revolution and civil wars 1910-1920 Between 1910 and 1920 Mexico was torn apart by a violent revolution and subsequent civil wars. In the first decade of the 20th century, President Porfirio Diaz ruled Mexico with an iron fist as an agent of the wealthy, undoing previous land reforms. Opposition grew against Diaz and Francisco I. Madero challenged him in the 1910 election. Madero was jailed by Diaz who declared he won the election. Revolutionary