In Thailand, every provincial capital city has its own city pillar, known in Thai as lak meuang (หลักเมือง), which is believed to house the city's guardian spirit. The pillar is usually made of wood and placed in a shrine called sahn lak meuang (ศาลหลักเมือง), which represents the centre of town, as well as the point from where distances between cities are measured. As such, it is comparable to the Greek omphalos (ὀμφᾰλός), i.e. the ‘navel’ or ‘knob’, which in Ancient Greece represented the center of the world and in Delphi was symbolized by a linga (लिङ्ग)-like knob. Whereas the word phalos (φᾰλός) seemingly has an etymological connotation to the Greek word phallos (φαλλός), i.e. ‘phallus’, the Thai lak meuang also typically takes a phallus-like shape. It is sometimes referred to as sao inthakhin (เสาอินทขีล), i.e. ‘barrier post’ or ‘guardian pillar’. In a way, city pillar worship is comparable with the linga worship found all over South and Southest Asia. In the capital Bangkok, the pillar shrine is loctaed opposite to the Royal Grand palace and has not one but two pillars, with one pillar housing the city's guardian spirit, the second pillar houses the guardian spirit of the nation. Adjacent to it, there is another shrine that houses a number of deities that are believed to protect the nation, such as Phra Siam Thewathiraat (พระสยามเทวาธิราช), the guardian spirit of Thailand; Chao Pho Ho Klong (เจ้าพ่อหอกลอง), a protective deity who is said to be the spirit of Chao Phraya (เจ้าพระยา) Si Surasak (สีห์สุรศักดิ์), an important military leader from the Thonburi (ธนบุรี) period, who in battle used to encourage his troops by beating a war drum, so when after his death, people sometimes heard drumbeats coming from his drum whilst no one was near, each time just before something bad was about to happen, as if it were a supernatural warning sign, Chao Pho Ho Klong became the spirit that safeguards the population by warning them for looming dangers; Phra Song Meuang (พระทรงเมือง), the deity in charge of watching over, as well as maintaining the various governmental departments and ministries, and who is also responsible for protecting the welfare and happiness of the country's citizens; Phra Seua Meuang (พระเสื้อเมือง), the deity in charge of protecting the country, both on land and in the water, who watches over the military forces and troops, and keeps the Kingdom free of foreign invasion; Phra Kaan Chai Sri (พระกาฬไชยศรี), a servant of Phra Yom (พระยม), the god of death, and who is responsible for sending the souls of sinners to hell; Chao Pho Chetakup (เจ้าพ่อเจตคุปต์), the scribe who records the good and bad deeds of mankind, etc. At the pillar shrine in Bangkok, there is also a hall where one can make an offering of thanks in the form of a paid musical and dance performance. This practice, known as kaebon (แก้บน) is made as a votive offer near an important shrine, where one earlier prayed or asked for a good result from an event or occasion, after fulfillment of that promise.