[ISHMap-List] R: A critical review of the hypothesis of a medieval origin for portolan charts
giuliopizzati at yahoo.it
Sat Mar 15 21:10:11 CET 2014
Read "THE FOUR SURVEYORS" or "RENDER UNTO CAESAR..." by Giulio Pizzati in Google Books or Researchgate.
Il sab 15 mar 2014 08:36 CET, Luis Robles ha scritto:
>I received this news last Wednesday through from Frank Jacobs's "Strange
>Maps" blog in BigThink (
>I assume that many of you must have received it too but just in case I
>thought I should post it here for general information.
>*Roel Nicolai*, a PhD student at the University of Utrecht, presented last
>March 3 his doctoral dissertation entitled *A critical review of the
>hypothesis of a medieval origin for portolan charts*. He reached several
>provocative conclusions that I expect will stir debate among the members of
>the list. The book is not available online yet, but in the University's
>website there is a press
>English from which I have extracted the following statements:
> - "A mathematical analysis of the oldest surviving portolan has revealed
> that its source data must have been derived from a portolan chart - instead
> of the other way round."
> - "it is unlikely that the nautical compass was available in time and
> that navigational methods used at that time were sophisticated enough to
> determine distances at such a degree of accuracy"
> - "Nicolai has also established that portolan charts were drawn on the
> Mercator projection, or a similar type of projection."
> - "they were much further advanced in terms of knowledge in the Middle
> Ages than we think"
> - "An Arabic-Islamic origin is highly unlikely, according to Nicolai."
> - "It therefore seems plausible that portolan charts originated from a
> tradition that is now lost. It is an intriguing question from what culture
> that tradition stemmed. Further research will be required to establish
> whether or not Greco-Roman antiquity is a realistic option, says Nicolai."
>The university does not say whether Mr Nicolai was awarded the doctorate or
>how to get access to his publication.
>Luis A. Robles Macías
>Profile in Academia.edu <http://independent.academia.edu/LuisRoblesMacías>
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