Earthly Branches

The Earthly Branches provide one system for reckoning time.



This system was built from observations of the orbit of Jupiter. Chinese astronomers divided the celestial circle into 12 sections to follow the orbit of ''Suìxīng'' . Astronomers rounded the orbit of Suixing to 12 years . Suixing was associated with ''Sheti'' and sometimes called Sheti.



In correlative thinking, the twelve years of the Jupiter cycle also identify the twelve months of the year, twelve animals , directions, seasons, months, and in the form of double-hours. When a Branch is used for a double hour, the listed periods are meant. When used for an exact time of a day, it is the center of the period. For instance, 午 means noon or a period from 11am to 1pm.



Chinese seasons are based on observations of the sun and stars, not the weather. Many Chinese calendrical systems have started the new year on the first new moon after the .



The Earthly Branches are today used with the Heavenly Stems in the current version of the "traditional " and in Taoism. The Ganzhi combination is a fairly new way to mark time; in the Shang era it was the ten Heavenly Stems that provided the names of the days of the week. The Branches are as old as the Stems , but the Stems were tied to the ritual calendars of Chinese kings. They were not part of the calendrical systems of the majority of Chinese.







Some cultures assign different animals: Vietnam replaces the ox, rabbit, and sheep with the water buffalo, cat, and goat respectively; Japan replaces the pig with the wild boar.

Directions

Even though Chinese has words for the four cardinal directions - , , , and - Chinese and astronomers/astrologers preferred using the twelve directions of the Earthly Branches, which is somewhat similar to the modern-day practice of English-speaking pilots using ''o'clock'' for directions. Since twelve points were not enough for sailing, twelve midpoints were added. Instead of combining two adjacent direction names, they assigned new names as follows:



* For the four diagonal directions, appropriate trigram names of I Ching were used.

* For the rest, the Heavenly Stems were used. According to the Five Elements theory, east is assigned to wood, and the Stems of wood are and . Thus they were assigned clockwise to the two adjacent points of the east.



Following is a table of the 24 directions:





{|class="wikitable" table border="1" cellpadding="3" cellspacing="0"



! ?

!Character

!Chinese
name

!Japanese
name

!Direction



|-tr align="center"

|1

|子||zǐ||ne

|0°




|-tr align="center"

|2

|癸||guǐ||mizunoto

|15°



|-tr align="center"

|3

|丑||chǒu||ushi

|30°



|-tr align="center"

|4

|艮||gèn||ushitora

|45°




|-tr align="center"

|5

|寅||yín||tora

|60°



|-tr align="center"

|6

|甲||jiǎ||kinoe

|75°



|-tr align="center"

|7

|卯||mǎo||u

|90°




|-tr align="center"

|8

|乙||yǐ||kinoto

|105°



|-tr align="center"

|9

|辰||chén||tatsu

|120°



|-tr align="center"

|10

|巽||xùn||tatsumi

|135°




|-tr align="center"

|11

|巳||sì||mi

|150°



|-tr align="center"

|12

|丙||bǐng||hinoe

|165°









Advanced mariners such as used 48-point compasses. An additional midpoint was called by a combination of its two closest basic directions, such as for the direction of 172.5°, the midpoint between , 165°, and , 180°.