From The Food Encyclopedia by Jacques Rolland and Carol Sherman
Made by forcing steam through finely ground coffee to make a strong brew, served in a demitasse. There are several stories about its origin. Probably because the word is Italian for "express", many say it was first made at a Milan train station as people boarded the express trains, an idea supported by the fact that it's usually taken standing and drunk quickly for a flavorful boost of energy. The coffee maker was called macchina a vapore, or "steam machine", invented in Naples in 1901.
