Iohannes de Sacrobosco's "Tractatus de Sphæra" was written around 1230. After the developement of printing in Europe, in the 15th century, it underwent successive editions, alone or with comments and together with additional works. It was widely studied in many European universities, up to mid-17th century. 

     A survey describing more than 200 editions of the "Tractatus de Sphæra" can be consulted here:

     The full text of the 1478 edition of Iohannes de Sacrobosco "Tractatus de Sphæra" can be consulted or downloaded from this address:

     The Latin text of the 1478 edition, together with a Portuguese translation, can be downloaded from this address: 

An edition of Sacrobosco's Tractatus de Sphaera, published in Venice in 1482 (copy of the Portuguese National Library, Lisbon).

Roberto de Andrade Martins
Group of History, Theory of Science and Science Teaching
State University of São Paulo (USP), Brazil