English: An engraving from the French Almanac of 1687, by an unknown artist, depicts the carriage of a royal missive of King Narai of Ayutthaya to King Louis XIV of France, using a portable castle called butsabok.

The diplomatic mission bringing the royal missive from Ayutthaya to France, led by Kosa Pan, arrived in Paris on 1 September 1686 CE.

The original description is as follows:

"Almanach pour 1687: ambassade du Siam à Versailles en 1686, 1687

"This engraving represents the arrival at Versailles, on September 1, 1686, of the letter engraved on a gold leaf sent by the King of Siam (Thailand). The eldest of the Siamese ambassadors knew the court of the Emperor of China Kangxi and his master, King Phra Naraï (1633–1688), wanted to know how the court of Versailles supported the comparison with that of China.

"Approaching the Ambassadors' staircase [the butsabok], one cannot help but be stunned by its majesty. One could justify crossing oceans to see nothing but this monument. But impassively we continue on. The drums and trumpets, with their strangely harmonious racket, smother the comments of the onlookers as they point to our outfits. One thousand five hundred glares testify to the importance of this day, and accompany us through salon after salon, each rivalling the other in its splendours, right up to the hall where we await the king."