J'aimerai ajouter aussi que suite à cette article on a eu l'honneur d'être contacté par l'auteur de l'article sur Koh Tao dans le wikipedia version anglaise. Voir le message ci-dessous.
Il nous éclaire sur certaines variations concernant les coordonnées maritimes telle qu'elle doivent être interpréter pour l'époque.

Il nous demandais aussi des informations sur le nom Kubia (donc voir texte en thailandais ci-dessus pour ça).

Voici son message :

Salut

I was the person who did the original research in the Koh Tao / Pulo Bardia connection and published some very brief details on Wikipedia. It was part of a study I was doing on marine history in respect of a distant seagoing ancestor who I believe was in the area in the 1690s.

At the time when the earliest maps of the area were published by Dampier, Thornton etc, marine navigation out of sight of land was limited to approximately 1 degree longitude or 60 nautical miles.This was in part due to the limitations of the 'Longstaff' and in part to the inaccuracies of mapping at the time. Therefore, when comparing co-ordinates listed in old publications or maps, one must not fall into the trap of comparing to today's super-accurate (~5m) fixes but must remember that 60 nautical miles is the possible magnitude of error.

Furthermore, the Prime Meridian was not universally adopted until the 1880s and any co-ordinates and maps need to be corrected back to the relevant meridain - often a point in mid-Atlantic, some 30 degree west of Greenwich.

I like your comments on the Chinese name for Koh Tao but you don't cite any documentary evidence of this.

Overall, welldone! A far more complete account that I put in the public domain but continaing some 'fuzzy logic'!