Ragioni Antique (1470-1561)
The Ragioni Antique dell'arte del mare et fabriche de vasselli is a manuscript with 67 large format folios, dating from the late 15th century and the first half of the 16th century (more precisely 1470-1561), bearing several different hand writings (eight, to be precise), whose author is unknown. It was started in 1470 and handed down until the mid 16th century. It's original is in Greenwich, in the National Maritime Museum, Cid. NVT.19.
As Father John describes it "there are texts that illuminate various facets of contemporary navigation: portolans describing the coastlines, charts for the position of the stars and sun an moon, lists of months that are unluky for sailors, discussions of tidal action, and accounts of the results of lead soundings." But it also includes texts on shipbuilding: "it has materials found in the Florence and Vienna codices (Father John is referring here to the text of the Libro di Marineria, or Fabrica di Galere), including the reference to the light galley designed by Theodoros Baxon."
This manuscript was studied by Alvise Chiggiato and by Father John McManamon. Although called "ragione antique" (ancient methods) it pertains to the design of watercraft with pre-designed frames and the use of molds and gauges to vary the width and dead rise of the floor timbers in a smooth, but not graphically pre-determined manner. 1
1. Filipe Castro 2002, ShipLab Website Nautical Archaeology Program, Texas A&M University
The Timbotta manuscript is available through: Chiggiato, Alvise, "Le Ragioni antique dell'architettura navale" in Dosio, Giorgetta Bonfiglio et al., ed., Razioni antique spettanti all'arte del mare et fabriche de vasselli, Venice: 1987, lvii lxxix.
McManamon, John, "The "Archaeology" of Fifteenth-Century Manuscripts on Shipbuilding," INA Quarterly (2001) 28.4: 17-26.