Organum Mathematicum

The Organum Mathematicum was an information device or teaching machine that was invented by the Jesuit polymath and scholar Athanasius Kircher in the middle of the 17th century.

With proper instruction and use, the device could assist in a wide assortment of calculations, including arithmetic, cryptography, and music.

Kircher adopted some of the ideas in the Organum from preexisting inventions like Napier's bones, almanacs, and his own Arca Musarithmica.

Yet, due to its general lack of adoption, it remains an interesting but obscure footnote in the history of information technology.

[2] In 1661, 11 years after the publication of Musurgia Universalis, which contains a description of a similar, but more limited device, the Arca Musarithmica, Kircher sent an Organum Mathematicum to Gottfried Aloys Kinner, the tutor to the 12-year-old Charles Joseph, Archduke of Habsburg, for whom the Organum was likely intended.

The device described in Schott's book was divided by functionality into 9 main sections, each of which contained approximately 24 rods.

This section had tables describing movements for the visible planets, and the constellation Draco, and also provided astrological interpretations for the 12 zodiac signs.

The rods in this section could be used to encrypt and decrypt text using a cyclic transposition cypher, based on a keyword.

Kircher's earlier Arca Musarithmica was a music composing device of similar design to the Organum.