The Mummies of Guanajuato, Mexico seen here c. 1911. As long as a yearly fee was paid the bodies of the dead were numbered and registered and cared for but if payment was discontinued the bodies were cast on a heap of bones and skulls. The dry rarefied air of Guanajuato provides an environment which can lead to a type of natural mummification. This place was subsequently turned into a museum called El Museo de las Momias (The Museum of the Mummies) in 1969. From The Wonders of the World, published c.1911.