| Timespan | Meridian | Yuan Source point |
| 03:00-05:00 | Lung | LU-9 |
| 05:00-07:00 | Large Intestine | LI-4 |
| 07:00-09:00 | Stomach | ST-42 |
| 09:00-11:00 | Spleen | SP-3 |
| 11:00-13:00 | Heart | HT-7 |
| 13:00-15:00 | Small Intestine | SI-4 |
| 15:00-17:00 | Urinary Bladder | UB-64 |
| 17:00-19:00 | Kidney | KI-3 |
| 19:00-21:00 | Pericardium | PC-7 |
| 21:00-23:00 | Triple Burner | TB-4 |
| 23:00-01:00 | Gall Bladder | GB-40 |
| 01:00-03:00 | Liver | LR-3 |
Na Zi Fa - Yuan Source points
Yuan Source points are the the 5-element points where the Yuan Qi (the original Qi) gathers. Therefore Yuan they play an important role to draw Qi into the meridian or expell pathogens from it.
Yuan Source points on the Yin meridians (always the same as the Shu Stream point) can be used to feed the 5/6* Yin organs (Lung, Spleen, Heart, Kidney, Pericardium* and Liver. Yuan Source points on the Yang meridians are merely used to expell pathogens and excesses.
Between 11:00 and 13:00 local solartime the Heart meridian is open.
The Yuan Source point of the Heart meridian is HT-7.
Modern Application
Because Yuan Source points influence the original Qi, these points are used to replenish energy in deeply deficient conditions, especially on the Yin meridians.
When the Yuan Source point is combined with other chronoacupuncture points like Inner Energy branch points, Luo connecting points of the coupled meridian or Luo connecting points on the opposite of the Zi Wu cycle, treatments become more powerfull than when the Yuan Source points are used alone.
