In centuries past, as H.G. Quaritch Wales explains in Siamese State Ceremonies, it was forbidden for a commoner even to touch royalty - even to rescue them if they were drowning. On board the royal barges there are, or were until recently, bundles of cocoa-nuts intended to be thrown to the king or any member of the royal family in the event of the barge foundering, for it was forbidden on pain of death for any person to lay hands on royalty to save them from drowning. A well known instance of the operation of this taboo is the tragic death of King Rama V’s first queen, who was drowned in full view of numerous bystanders who dared not save her. [Quaritch Wales, Siamese State Ceremonies] He provides a translation from the Kata Mandirapdla, or Book of Palace Law, a royal manuscript dated 1805 and said to have existed in almost the same form from about the 15th century: If a boat (royal barge) founders, the boatmen must swim away; if they remain near the boat they are to be executed. If the boat founders and the royal person falls into the water and is about to drown let the boatmen stretch out the signal-spear and throw the cocoa-nuts so that he may grasp them if he can. If he cannot, they may let him seize the signal-spear. If they lay hold of him to rescue him they are to be executed. He who throws the cocoa-nuts is to be rewarded with forty ticals of silver and one gold basin. If the barge sinks and someone else sees the cocoa-nuts thrown and goes to save the royal person, the punishment is double and all his family is to be exterminated. If the barge founders and someone throws the cocoa-nuts so that they float towards the shore (i.e. away from the royal person), his throat is to be cut and his home confiscated. [Kata Mandirapdla, quoted in Quaritch Wales, Siamese State Ceremonies] The worst offence of all was to touch the head of a king. Quaritch Wales says sensible considerations underlay this ancient taboo:

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