What Is City Wall Earth (Cheng Tou Tu)?
In a Nutshell
The NaYin of the Wu Yin and Ji Mao stem-branches: earth of the city walls — tall, solid, immovable.
Quick facts
| Item | Detail |
|---|---|
| Stem-branches | Wu Yin, Ji Mao |
| NaYin element | Earth |
| Signature image | The capital's jade ramparts, the imperial city's golden walls |
What is City Wall Earth?
City Wall Earth is one of the thirty NaYin (Melodic Elements) groups of the sexagenary cycle, covering the two stem-branches Wu Yin and Ji Mao. The sixty stem-branches are taken two at a time, in order, forming thirty groups; each group has its own NaYin name, and the Wu Yin–Ji Mao group is called "City Wall Earth." Within any group, both stem-branches always share the same NaYin — a basic rule of the system.
A stem-branch's own elements often differ from its NaYin. Wu is an Earth stem and Yin a Wood branch, yet the NaYin here is Earth — check the chart rather than assuming.
"City wall" fixes the image: the earth piled atop a city wall. The *San Ming Tong Hui* glosses it as "the heavenly capital's jade ramparts, the imperial seat's golden walls" — like the jade battlements of the capital and the fortified walls of the imperial city, it takes the lofty, unshakeable image.
How to look it up: match the stem-branch of your Year Pillar or Day Pillar against the NaYin chart. For example, 1998 was a Wu Yin year and 1999 a Ji Mao year, so anyone born in those years carries City Wall Earth as their Year Pillar NaYin; a Wu Yin or Ji Mao Day Pillar works the same way. MoZhu's built-in NaYin lookup tool generates the NaYin of all Four Pillars automatically from a birth time.
Early practitioners gave the Year Pillar NaYin (the "year-destiny") great weight; since the Song dynasty, the Zi Ping school centers on the Day Master, and NaYin has mostly receded to auxiliary reference. Names like City Wall Earth are the ancients' evocative nicknames for stem-branch pairs; the imagery helps you read the classics, but nothing should be inferred from the name alone. This page is for study and reference only.
Classical sources
"The heavenly capital's jade ramparts, the imperial seat's golden walls."
(Rendered from the classical Chinese original.)
Source: *San Ming Tong Hui* (Comprehensive Treatise on the Three Destinies), Book 1, *Lun Wu Xing* (On the Five Elements — the section on Earth)
Plain-language reading: City Wall Earth takes the image of earth on the city walls — the capital's jade battlements, the imperial city's fortified walls: lofty, solid, immovable.
*For entertainment purposes only.*