In Qian times, the official almanac was named Shixian Shu and was published every year. The official Wannian Shu/Wannian Li (calendar of 100 or, in some editions, 200 years) was first edited in 1741, and the calculations were based on the meridian at longitude 116°23' East.After the end of the imperial era in 1911, the government of China announced the abolition of the traditional Chinese calendar (Huangli) and using the Gregorian calendar as standard calendar. The government kept publishing official almanacs, but the information about day-selection was excluded. So, entrepreneurs began producing popular almanacs. In order to enhance their sales and the popularity, they included methods and rules of day-selection laid down by religion, unorthodox divination, magical charms, etc. in their almanacs.
In 1953, there were two versions of the traditional Chinese calendar in Mainland China and in Hong Kong. According to the version which was based on the Wannianli of Xuantong imperial era, the 6th lunar month was a "small month" (29 days) and the 7th lunar month was a "big month" (30 days). However, the other version which was based on the calculations of Purple Mountain Observatory was just the opposite - it stated that the 6th month was a "big month" and the 7th month was a "small month". The same difference occurred in 1978 and 1989. In 1978, Guangzhou people in mainland China and Hong Kong people celebrated Mid-autumn festival in different days. Therefore, if you take Wannianli as your reference to traditional Chinese calendar or Jieqi, be aware that there may be some differences among Wannianlis from different sources. Through the above mentioned incidents we understood why in times past each regime tried to monopolize production of the annual almanac and outlawed unauthorized productions.
Generally speaking, day-selection is a study of learning the relations between the influences of horizon directions and time / the locations of planets. Shensha is the general term for these influences of horizon directions. In general, shen means good influence, sha means baneful influence, and all of shensha actually do not relate to any ghosts and celestial beings.
Ancient people believed that particular days of the year were not suitable for certain activities. They set some simple rules to determine whether activities would be auspicious or inauspicious at any given moment, in any given place. Some of these methods, like Jianchu system and 28-xiu system which passed down from the period before Pre-Han, are included in modern Chinese almanacs. As for the accuracy, try at your own risk. Many people use day-selection only because they follow customs and tradition and want to free from anxiety.
Spring Ox
The description of the spring ox and the god of plant (Mangshen) with woodblock representation appear on the first page of the Chinese Almanacs (also known as Tongshu, Tongsheng, and Tung Shu) is customary rules of making clay bull for the "beating the spring" or "whipping the bull" ceremony. Before the end of the imperial era in 1911, the "beating the spring /whipping the bull" ceremony was held on the day Li Chun in order to represent to send away the cold and to welcome the spring, and a clay bull was set up outside the eastern gate of the city at the day before Li Chun (Beginning of Spring). According to ancient Chinese tradition,Warring States period and Han period, a clay bull was set up outside the eastern gate of the city in order to represent sending away the cold in the 12th month.
Description of spring ox and the god of plant for AD 2004
Spring Ox Symbolizing height 4 Chi
(Chi, a unit of length
1 Chi = 1/3 meter
1 Chi = 10 Cun
1 Cun = 10 Fen)four seasons length 8 Chi eight seasonal nodes length of tail 1 Chi 2 Cun 12 months head blue Jia 
(Year stem)body white
Shen 
(Year branch)abdomen black Water
(Na Yin of the year)horns, ears and tail black
Gui 
(Stem of Li Chun day)shins yellow
Chou 
(Branch of Li Chun day)hooves blue
Wood
(Na Yin of Li Chun day)tail bended to left Yang year mouth open
Yang year strap rein yellow silk rope Gui Chou
(Stem and branch of Li Chun)clasp made with mulberry wood stepping board the left door plank Yang year Mang Shen
(God of plant)height 3 Chi 6 Cun and 5 Fen 365 days man old man-like face Shen
(Year branch)clothes blue Ke, Earth is subdued by wood
(the element which subdues the day-branch)waist band white Sheng, metal gives birth to earth
(the element which the day-branch gives birth to)hair worn in two buns above ears Wood
(Na Yin of Li Chun day)hat carried in right hand Xu (Shi) 
(The time of Li Chun)
(Shi, a unit of time,
equal to two western hours)stockings, shoes and pants having shoes,
hanging stockings on right side
Wood
(Na Yin of Li Chun day)whip made with withy
length of whip 2 Chi 4 Cun 24 Jieqi knot made with colored (five colors) silk
Chou
(Branch of Li Chun day)Mang Shen
(God of plant)leisurely stand next ox
at leftt side to the ox at evening
Li Chun occurs after the first new moon
more than five days,
Yin year
Five Dragons manage water
This is an ancient method of predicting annual rainfall. The number of dragons means the number of days from the lunar new year to the first day with earthly-branch Chen. Large number bodes less rainfall, less number bodes more rainfall. As for the accuracy, a scholar wrote in his book that in Yiyou year of Chongning era it was a large amount of rain falling from spring to autumn even though eleven dragons managed water.
Diagram of Liunian Dali
(Diagram of Auspicious Directions of the Year)
Almanacs from the caves of Dunhuang reveal that the Purple-white / Jiugong / Nine-palace system was employed in almanacs not later than the eighth century. This system was included in the chart of Liunian Dali (Diagram of Auspicious and Inauspicious Directions of the Year) on the second page of Chinese Almanacs. In the chart of Liunian Dali, eight trigram names represent the basic eight compass directions. Li represents south, Kan represents north, Zhen represents east, Dui represents west and so on.
This Nine Palace system is known as Lishu Sanyuan Baifa (Calendrical Three Period White Method). Nine palaces represent eight directions plus center, and each palace houses a number (also known as star-spirit) for the year. Each number only just is the symbolic of the probable influence, but not the certainty, in the direction.
In general, the direction of "Yellow Five" is considered as inauspicious. In 2004 the "Yellow Five" direction occupies the central house. The general advice is to keep this direction calm. If there is a door or window in this direction, simply hanging a metal wind-chime or metal windmill on the outside of the door or window can prevent the stellar influence causing illness. Please note that, in Ganzhi calendar and this system, years are measured from Lichun to Lichun. And, different systems divide full 360 deg direction into different numbers of segments. In Four-pillars astrology, the full 360 deg direction is divided in 12 segments.
4 9 2 3 5 7 8 1 6 Purple-white chart for 2003 Calculating the annual and monthly purple-white chart (Java applet)
Compass Directions
In the Pre-han times the compass was divied into 12 sectors of 30 degrees each by names of 12 terrestrial/earthly branches. From the Tang period, Fengshui compass (also known as Luojing) was divided into 24 sectors of 15 degrees each by names of 12 terrestrial/earthly branches and 8 heavenly stems and four names of trigrams.
Measuring the direction
In the past times, houses were built of stone and wood. People just simply placed the compass or Chinese Luojing on either end of the threshold to measure the horizon direction perpendicular to the main door (also facing direction of the house), and didn't need to care about the magnetic interferences.
It is unnecessary to buy an expensive Chinese compass (luojing). Since the compass or luojing is based upon a magnet, the compass needle can be influenced by ferroconcrete, nails in wall, power lines, electric motors, etc. To take a correct reading on the compass, any sources of magnetic interference should be avoided. Place the compass on the wooden stool that has been constructed with wooden pegs (no nails) or plastic stool few feet away from the door. Care is taken to assure that the compass is away objects containing iron, wires, and equipment that might interfere with its operation. Go and get a string, and fix one end of the string to the door frame. Stretch the string across the compass, and superimpose it upon the center of the compass. Simply pointing the needle to "N" north or 0 degrees, a reading can be taken. Make sure that the string is perpendicular to the main door and is superimposed upon the center of compass, and the compass is level.
Taisui is in Wei Direction
Many people confuse the Taisui with Jupiter because both of Taisui and Jupiter were called Suixing (Year-star) in ancient times. Taisui actually means the direction having the same name as the terrestrial/earthly branch of the year. In 2004, the Taisui occupies the Wei direction, from 195° to 225°. In the above mentioned purple-white system, the Taisui means the "Blue-three" and occupies southwest, from 202.5° to 247.5°.
24 Jieqi
Term Date
(year/month/day)Time The sun enters 1st Jie Lichun Beginning of Spring 2004/02/04 19:57 1st Qi Yushui Rain Water 2004/02/19 15:50 Hai house 2nd Jie Jingzhe Waking of Insects 2004/03/05 13:56 2nd Qi Chunfen Spring Equinox 2004/03/20 14:49 Xu house 3rd Jie Qingming Pure Brightness 2004/04/04 18:43 3rd Qi Guyu Grain Rain 2004/04/20 01:50 You house 4th Jie Lixia Beginning of Summer 2004/05/05 12:02 4th Qi Xiaoman Grain Full 2004/05/21 00:59 Shen house 5th Jie Mangzhong Grain in Ear 2004/06/05 16:14 5th Qi Xiazhi Summer Solstice 2004/06/21 08:57 Wei house 6th Jie Xiaoshu Slight Heat 2004/07/07 02:31 6th Qi Dashu Great Heat 2004/07/22 19:50 Wu house 7th Jie Liqiu Beginning of Autumn 2004/08/07 12:20 7th Qi Chushu Limit of Heat 2004/08/23 02:53 Si house 8th Jie Bailu White Dew 2004/09/07 15:13 8th Qi Qiufen Autumnal Equinox 2004/09/23 00:30 Chen house 9th Jie Hanlu Cold Dew 2004/10/08 06:50 9th Qi Shuangjiang Descent of Frost 2004/10/23 09:49 Mao house 10th Jie Lidong Beginning of Winter 2004/11/07 09:59 10th Qi Xiaoxue Slight Snow 2004/11/22 07:22 Yin house 11th Jie Daxue Great Snow 2004/12/07 02:49 11th Qi Dongzhi Winter Solstice 2004/12/21 20:42 Chou house 12th Jie Xiaohan Slight Cold 2004/01/05 14:03 12th Qi Dahan Great Cold 2004/01/20 07:22 Zi house 1st Jie Lichun
(2005,
Year Yi You)Beginning of Spring 2005/02/04 01:43 Calculations are based on Chinese coast time, the meridian at longitude 120° East.
Please refer to Chinese Calendar for 24 Jieqi.
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