Tiago Miguel Fraga
Thesis: December 2007
Chair: Castro
Nautical Archaeology Program
Buy a puzzle, assemble it, and destroy its original box. Take the puzzle, go to
a lake, throw the puzzle in the lake, and leave it for a few weeks. Return to
the lake and try to rebuild the puzzle from the remaining pieces. Such is the
challenge of the research goals presented on this abstract – the reconstruction
of a Portuguese frigate, Santo Antonio de Tanná, from its submerged remains.
This thesis focuses on the mechanisms of reconstructing the ship, including the
thought process, new computer tools, and imagination required for an
archaeologist to be a detective of lost eras. The main objective was to
understand the construction of a late Seventeenth-century Portuguese frigate.
Frigates were responsible for patrolling the seas, intercepting fastmoving
vessels, re-supplying military trading stations, and protecting trade routes.
The existence of Portuguese frigates was known from historical records, but
Santo Antonio de Tanná is the only frigate identified in the archaeological
record. As such, its reconstruction should enable scholars to better understand
the actual capabilities of seventeenth century frigates. iv A particular
challenge in this study was ascertaining the manner in which Santo Antonio de
Tanná’s construction reflected the state of affairs of the Portuguese trade
network. Although their construction methods were advanced, the Portuguese
adopted a shipbuilding design that was not able to compete as well in the new
conditions of a changing global context. This study clearly demonstrate that
cargo capacity was given greater emphasis than either speed or maneuverability,
illustrating the on-going necessity of the Portuguese to build military ships
with cargo capacity sufficient for minimal trade, even at the expense of speed.
These were just the first steps in terms of what could be learned from the
reconstruction. The best method to understand the ship, a three-dimensional
object, was to recreate it into a three-dimensional environment in order to
create a more accurate model. The resulting model permitted research to extend
beyond the limits of the individual line drawings through the added benefit of
being able to calculate hydrodynamics, sailing characteristics, and other data
based on the ship’s morphology.