The following is an account of a public execution as witnessed by P.A. Thompson towards the end of the 19th Century:

Though murder is not an uncommon form of crime, the death sentence is rarely passed in Siam, and still less often carried out. Executions are public, but not very many, even amongst the Siamese themselves, have ever seen one. It was quite by chance that once, as I was travelling far up the Bangpakong River, that I passed a boat full of soldiers with a prisoner in their midst, and found that the man was to be beheaded that day. No secrecy seemed to have been observed here, for there were more than a hundred people assembled when I landed, and amongst them the Governor of the district.

When the condemned man arrived he was handed over to the monks, who spent the morning in preaching to him, but he appeared to derive little comfort from their words. When this was over he was allowed to ask for anything that he wanted, but he only desired a little rice. It is said that condemned men are often given opium, but this man had none. It seems that he had been lying in prison under sentence of death for two years, and this delay, which is perhaps the most objectionable feature of the whole business, is not uncommon.

During the morning the executioners built for themselves a little room of leafy boughs. It was to be the "green-room" for the succeeding tragedy, and in the centre of the stage they had planted a bamboo stick, with a cross-piece about two feet from the ground. To this the condemned man was led. He sat cross-legged on the ground with his back to the bamboo, and his arms, closely pressed against his sides, were tied at the elbows to the cross-piece; but with this exception he was left free to move. Then one of the executioners, kneeling beside him, filled his ears with clay and gave him lighted joss-sticks to hold. At times, also, he appeared to stroke the condemned man's face, almost as though he were trying to mesmerise him, but if such was his object it was of no avail, for the poor wretch was quite unnerved and the joss sticks fell un-heeded to the ground.

Now the second executioner came out, dressed in red with a red band bound round his forehead, and carrying a sword. He advanced until the condemned man could see him out of the corner of his eye, and there, some twenty yards away on the man's right hand, he sat upon his heels, and appeared to wait the moment when he should strike. Thereafter, the condemned man kept his head turned towards him, looking over his right shoulder. Meanwhile, the first executioner had swiftly run back and donned the red dress. He now entered the wide ring of spectators almost directly behind the condemned man, but during his stealthy advance, he kept always on his left hand. Wai-ing once to the Governor, and then raising his joined hands to heaven, he took his sword - a long slightly curved blade broadening towards the point, with thick heavy back and edge keen as a razor. Then he danced out with half-a-dozen prancing steps in tiptoe, and then stopped with one foot in the air. His sword was held above his head, one hand grasping the handle and the other fingering the point.

So, in a series of little rushes, varied by extraordinary posturing and twirling of his sword, he crept nearer and nearer to his unsuspecting victim, amidst a silence that was painful. At the end his movements were so rapid that we could scarcely follow them. He was well out of striking distance when there came a quick rush, a circle of light in the air, and a sudden jet of crimson. He had not paused for the fraction of a second to take aim, but the head was severed with that single blow.

When all was over the monks came out again, and chanted over the dead man. They held a strip of cotton, and allowed one end to hang down and rest upon the body. Then the body was laid in a grave already dug near by, while the head was stuck upon a pole and left as a warning to evil-doers.

Source: Lotus Land: Being an Account of the Country and People of Southern Siam, 1906

I have been reading an interesting book called "The Last Executioner". The method of execution during the 20th Century was machine gun. The author was the last person to use this method. Today, execution is by lethal injection. I will type up some extracts from this book at a later date.