The Transorma was the first large-scale multi-position mail sorting machine, built by the Dutch heavy industrial company, Werkspoor. The name is an acronym for "TRANsport and SORting, Marchand and Andriessen", the last names of the inventors.
Transorma machines had up to five stations where letters were presented one at a time to operators who read the address, selected a routing code that was typed onto the front of the letter, and then sent it off to be automatically sorted into one of up to 300 chutes. Several models were offered; the first U.S. postal station to install a Transorma system used the "5/300" model, which supported 5 sorters and 300 bins. Smaller models, like the "1/150", were similar in concept but were operated by a single sorter and used and different mechanism for the sorting.
The Transorma was introduced in the Netherlands in 1927, and the first production version started operations in Rotterdam in 1930. Further sales in the Netherlands followed, but widespread adoption was interrupted by World War II. New installations followed after the war and the machines spread around the world during the 1950s. However, they were used for only a short period of time before computerized systems replaced them in the 1960s.