Alexandre de Chaumont sailing to Siam - 1685-1686

While Belisama crew was charging solar panels in Thailand over new year, we ended-up in Lopburi castle, where Alexandre de Chaumont, the ambassador of Louis the XIV, met the King of Siam in 1685. this was the result of a round-the-world trip shown on a map displayed in the palace.


 And indeed, this was quite a trip...
Louis XIV, convinced by a greek ambassador of the king of Siam that he would be willing to convert to christianity, send an ambassador to Siam in 1685, the Chevalier Alexandre de Chaumont, a well experienced factotum who gained his reputation in Quebec.

On the third of March 1685, the delegation left Brest onboard two ships, a king vessel called l'Oiseau and a frigate called La Maligne. On 31 May of 1685, they reach the Cape of Good Hope, after 85 days of sailing and only 40 miles off their intended destination despite navigating by means of dead reckoning (navigation à l'estime in French) since passing Cap Verde islands.

On 7 June, they depart from Cape of Good Hope, direction Batavia, alias Jakarta today. They encounter a much tougher sea and weather conditions on this segment, forcing them to get into the "roaring forties" in order to get supporting winds, and resulting in the two boats to get separated.



On August 13, l'Oiseau manages to pass the Sunda straight between the islands of Sumatra and Java (picture above), after four days of fighting head current, and anchored in the Banten bay. However, the Dutch resident did not grant them to disembark, and they had to set sail further to Batavia (Jakarta) with their 65 crew members suffering from scorbut.

When looking at the reproduction of the map of their trip from Brest in Lobpuri castle, one can only be astonished by the precision of the navigation at a time there was not mean (or almost) to estimate the longitude of a position while quite a few approaches had proven fine to estimate the latitude of a boat. Dead reckoning was the only trustable way of being located on a map, and for such long segment out of sight of the coast, it was a real challenge, as the various streams and drift could not be accounted for in this approach.

The reference for sailors like Alexandre de Chaumont was the book "Hydrographie contenant la théorie et la pratique de toutes les parties de la navigation" dated 1643. This was the holy time where a Jesuit priests at the top of the science of his time could write a treaty covering all aspects of navigation.

This book, available on Google books, is of much interest today, as it shows all the attempts at getting an accurate location of a boat at sea on a map, none of which were satisfactory at the time.

     

When Alexandre de Chaumont made it to Lobpuri, he presented a letter from Louis XIV to the king of Siam. The protocole imposed that Alexandre would crawl on his knees in front of the king, and pull his arm very high for the King to be able to take the letter. Instead, Alexandre de Chaumont refuel to crawl, and refuse to raise his elbow up, forcing the King of Siam to bend down to catch the letter. Mysteries of diplomacy!

It will take only another fifty years before Harrington will invent the clock that works at sea, finally allowing ships to get a precise estimate of the longitude. See the info on the Royal Museums Greenwich, and make sure to visit it if you ever have a chance to get to London.