See you at two drums? That means 8 p.m. in Thai time

Dear Six Hours Early,

Your friend was on time. สองทุ่ม (song thum) means 8 p.m., not 2 o'clock. Thailand runs two clocks at once. On paper it uses the 24-hour clock. Out loud, most people use an older count of six-hour blocks ¹.

Four blocks, and each one starts again at 1

The spoken clock cuts the day into four blocks of six hours. In each block the count starts again at one. Each block has its own word ¹²:

Noon is เที่ยง (thiang). Midnight is เที่ยงคืน (thiang khuen), "the noon of the night" ¹.

So the number two can mean 2 a.m., 2 p.m. or 8 p.m. The word next to the number names the block. The wrong block puts a person six hours early, or twelve hours late ¹. The shop opens at บ่ายโมง: 1 p.m.

Two small extras. At 4 p.m. people say บ่ายสี่โมง (bai si mong). Many also say สี่โมงเย็น, "4 gongs, evening". 5 p.m. works the same way ¹². And an older way counts the morning from one as well: สองโมงเช้า (song mong chao) for 8 a.m. The 12-hour way, แปดโมงเช้า, is the one heard more often today ².

A gong by day, a drum by night

Before clocks, keepers struck a gong (ฆ้อง, khong) through the day. Through the night they beat a drum (กลอง, klong). People named the hour by the sound they heard. โมง is the boom of the gong. ทุ่ม is the thud of the drum. ตี is the verb "strike" ¹³.

At 6 a.m. and 6 p.m. the keepers beat a long run of strokes, called ย่ำ (yam). Dawn was ย่ำรุ่ง (yam rung). Dusk was ย่ำค่ำ (yam kham) ¹². Thai Wikipedia gives both หกโมงเย็น and ย่ำค่ำ for 6 p.m. ³.

The king's list of 1900

In July 1900, the Royal Gazette (the Thai government's official paper) printed a list of hour names for King Chulalongkorn, Rama V. It said people were using some names wrongly. It named five forms to stop: 6 โมงเช้า, 6 โมงเย็น, 3 ทุ่ม, 6 ทุ่ม and 9 ทุ่ม ¹. English Wikipedia gives the year as 1901 ². The gazette's own date, Rattanakosin year 119, is 1900 ¹.

Today people say all five of the forms the list struck out ¹.

On paper: นาฬิกา and a coconut

Written down, and on the radio, Thai time uses the 24-hour clock. A time is written with น., short for นาฬิกา (nalika), "clock": 14.30 น. is 2.30 p.m. ¹.

นาฬิกา first meant a coconut. Siam kept time with half a coconut shell with a small hole in the bottom. It floated in a basin of water. When the shell filled and sank, one hour had passed ¹.

Half past, and ten more minutes

Half past is ครึ่ง (khrueng). บ่ายสองโมงครึ่ง (bai song mong khrueng) is 2.30 p.m. Other minutes take the number and นาที (nathi), minutes. Near the hour, people count down. อีกสิบนาทีสามทุ่ม, "ten more minutes to three drums", is 8.50 p.m. ¹.

The Telling Time in Thai page has a dial. Drag the hand, and it writes the time the way people say it. It plays a gong for โมง and a drum for ทุ่ม. Its eight-question quiz uses the usual mix-ups as the wrong answers: the same number in another block ¹.

After dark, every hour is a drum. Two drums: 8 p.m., and a friend at the café.