We have an Earth-shaped concept for a board, and some basic calendar-markers. Now let’s use a real board.

This is a liuren astrolabe, the device that was used for feng shui before the invention of the zhinan zhen or south-pointing spoon (the first magnetic compass).

Notice that our original set of calendar-markers seem to correspond with the markings on the liuren? They should, because the liuren was used to calculate the ci or Jupiter stations. But a liuren was much more.

If you can put the 12 ci on the board, which was common during the time of the Shang, you can also add a lot of other information that was available at the time — ganzhi, directions, and other important points of astronomy.

The taiji is shown because it, too, is astronomical: it is the pattern of the Sun’s movements in a year, found by using a gnomon. A gnomon is the oldest astronomical device. In China it was still used for ritual purposes, such as the siting of a capital city, as noted in the Zhouli.

This shows how the bagua (the Luoshu in this case) and the zhi correspond on the liuren. You may also notice that the East Group and West Group generally correspond to the dividing-line between yin and yang, which is determined astronomically. (North is the only exception to the correspondence; buried in the mists of the astronomy must surely be the reason for its inclusion in the East Group.)

But how old could all of this knowledge be? Here is an interesting discovery from 2006 with star markings. The notches on the side are thought by archaeologists and scholars to indicate the zhi. The stars indicate the sky of a time around when the “axe” was said to have been fashioned (this “snapshot” is 5 July 3100 BCE at 06:30).

That is all for this installment. The next one should be released in a week or so.