Digital Library

The Book of Michalli da Ruodo (Michael of Rhodes)

Title: Book of Michael of Rhodes

Author: Michalli da Ruodo (English: Michael of Rhodes; Italian: Michele da Rodi)

Year: 1434

Description: 440 pages

Owner: The original manuscript is privately owned

Call No.: n/a

Notes: The book was made available for study and publication by the Dibner Insitute for the History of Science and Technology in Cambridge, Massachusetts.

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View a digitized copy of select pages from the original document, translations into Italian or English, and a body of work explaining the history context, and contents of the book.

Michael of Rhodes Project

Dibner Insitute for the History of Science and Technology

Original & Translations

View Digitized Original and Translations from the Michael of Rhodes Project


The book is the oldest surviving treatise on shipbuilding, though it was certainly not the first written. In addition to formulas for building ships, it contains information on mathematics, navigation, how time was reckoned at sea, and astrology, as well as an account of the journeys the author took throughout his long career. Some parts of the book were copied from earlier manuscripts.

Portions of the book were also copied into other works. Michalli himself copied portions of it into another book, Raxion de’ Marineri (Method for Mariners), which was mistakenly attributed to Pietro di Versi until 2004. The shipbuilding portion was copied by humanist and collector Giovanni Battista Ramusio (1485-1557), and this copy became known as Fabrica di galere when it was rediscovered in Florence in the 1830s.

The original resurfaced in 1966 when it was put up for auction, but it was purchased by a private collector. When it was sold again in 2000, the new owner made it available to the Dibner Institute for the History of Science and Technology for study and publication.

The Author

Michalli da Ruodo, whose name is often translated to Michael of Rhodes (English) or Michele da Rodi (Italian), signed onto a Venetian war galley as a common oarsman (homo da remo) in 1401. Little is known of his life prior to this, or how he came to Venice from Rhodes. His book is written in the Venetian dialect, with the exception of two Greek prayers transcribed phonetically in Latin letters. Unlike most foreigners who enlisted in the Venetian navy, he rose through the ranks to attain significant professional success. He held the following positions:

  • Homo da remo (1401-1405) – common oarsman
  • Proder (1405-1406) – senior oarsman
  • Nochiero (1407-1413) – equivalent to an apprentice officer
  • Paron (1414-1420) – most junior of the three senior officers, reports to comito
  • Comito (1421-1434) – captain, reports to a noble patron (commercial galley) or sopracomito (military galley)
  • Armiraio (1422, 1428, 1436, 1440) – highest non-noble office in naval service, directed fleet, reported to noble captain of the fleet
  • Homo de conseio (1435-1443) – “man of the council” on commercial galley, elected by state officials from among experienced mariners; book may have been written to support his candidacy
  • Posted to Stadiera, the official weighing station of Venice (144-1445)



Michalli’s text promises to provide everything one needs to know to build the three galleys and two ships described. But he provides different information for the ships compared to the galleys.

Most ships at the time were designed using proportions in reference to the keel, and Michalli’s description of the nave latina and nave quadra follow this pattern. He provides the length of the keel, describes the midship frame using the piano (width of the floor), trepie (breadth three feet from the ground), bocha (maximum breadth at height of the deck), and lastly gives the length of the deck. The rest of the section is devoted to describing the outfitting and rigging of the vessels.

For the galleys, however, Michalli describes long lists of detailed measurements for specific components of ships, carefully organized by the order of construction. The fundamental measurements, key to designing most ships of its time, are partially or completely omitted for two of the three galleys. These ships in the state-sponsored Arsenal, and this description suggests they were built to a standardized plan.

Works Cited

Dibner Institute for the History of Science and Technology. (2005). Michael of Rhodes Project. Accessed August 20, 2019.

Additional Sources

Pamela O. Long, David McGee and Alan M. Stahl (eds.) of The Book of Michael of Rhodes: A Fifteenth-Century Maritime Manuscript. (Cambridge, MA: MIT Press, 2009)

  • Volume 1: Facsimile of the manuscript
  • Volume 2: Transcription and translation
  • Volume 3: Scholarly essays about Michalli, his manuscript, and the subjects he covered

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