Justine and I visited the British Museum in 1996, and we saw this funny object called a "cong". The museum claimed that they came from Chinese burial sites around 2000 BC, and nobody knew what they had been for. They were made of jade, had between 1 and 10 levels (the one in the picture has two), had a circular hole down the center, and were somewhat tapered. The levels were always shaped the same, and the height of a level was constant both within a cong and between congs from different times and places. A photo in the museum suggested that more than one cong might be found in a single grave.

Recently I saw another of these in the travelling Smithsonian exhibit. It had 10 levels, and was slightly tapered. They called it an "ancient Chinese ritual object".

I thought it might be a ruler of some sort. Justine thought that maybe it was how long the person had lived. Is anyone familiar with these things? Any clue what they might be? Tell me what you think.

These are the opinions I've heard so far:

George Ku thinks that these might be a symbol of military rank, there being 9 ranks in the ancient military. (If that theory is correct, one or two level congs would be made of wood, and bigger ones would become progressively more impressive.)

Andrew Perash says:

One thing I wish you'd post would be the cong's dimensions. Reading between the lines, I guess that they're too big to be worn. I saw someone suggested it symbolized some sort of social status: Guess that might make some lucky guy a *King Cong*. <ouch>

All jocundity aside, What are the resonance properties of jade? Perhaps it was a musical instrument? As such it might've been used as a totem to ward off evil spirits; like Tibetan priests blowing those great horns, hmmm?? How does jade percuss?

To which I respond:

I recall each level as being a little under two centimeters tall. I don't know how jade percusses.

Rick Walker proposes that these were an I-ching hexagram:

"I Ching" can be translated as the "easy way".  Perhaps the "cong" was 
meant to be a material embodiment of one of the particular 64 hexagrams
as an aid to the person on their "way" to a celestial afterlife.  

Let's look in more detail at this particular Cong example:
Rightside up:
    PmMPmM: implies PMMPMM changing to PPMPPM
Then flipping over:
    MmPMmPP: implies MMPMMP changing to MPPMPP

Since we flipped the cong, we are obliged to read the second progression
in reverse time order:
    PMMPMM   ->   PPMPPM   ->  MPPMPP  ->   MMPMMP
      (1)  (1->2)   (2)         (3)  (3->4)   (4)

A simple rendering of this from the I-Ching is:
        State 1) Keeping Still: Death or Meditation
1->2 transition) Swept along by forces beyond your control
        State 2) Penetrating Influence: Keep working towards the goal
        State 3) Joyous Encouragement: Your goal is now within reach
3->4 transition) Avoid distractions and associations with negative impulses
        State 4) Breaking Forth: Rebirth / Resurrection

Because every theory must have predictive value, I will "go out on a
limb" to say that the conical hole will be found to grow wider toward
state #4.  This is a way to symbolize an ever-easier transition through
the afterlife back into the physical realm.

Nancy Reynolds says,

Well, it reminds me of something I saw on a sci-fi show (I think it's
'Earth-Final Conflict' but not sure -- we watch so many sci-fis) - where
these bees came out of it, got into people, killed them ...it's a fuzzy
memory.

And boba-fett (er, somebody with an alias out there somewhere) says:

The Cong is from the Neolithic period (i.e. Prehistorical). No one
knows for certain what these objects represent but it is a safe bet to
assume that 
  1. they were highly venerated and 
  2. they had some religious purpose.  
Jades are extremely hard to come by especially large piece and given
the hardness of nephrite (real chinese Jade) jade was highly
prized. Most scholarly interpetations beleive that the tube represents
Heaven and is a modification of an even more ancient object known as
the Pi or Bi Disc. The square shapes represents earth (4 corner=4
directions) with Human faces/shamans (yes it's a face wearing a head
band with 2 circles for eyes, a nose, and sometimes mouths...by the
way your picture is upside down) and their mediums (in many more
elaborate Congs there are animals such as birds). Thus you have a
representation of The cosmos, with humans, earth and heaven
interacting.

Benoît Morrissette said:

... I am wondering how is it tapered exactly.  I imagine that if it is
the hole that is tapered, it is to fit on a wooden pole.  A cong fitted
on a walking stick might make a sceptre, the number of level indicating
the rank of the person.  Perhaps many congs could be placed on top of 
the others to indicate higher ranks.
 
boba-fett suggested that your picture is upside-down.  If the taper of 
the cong is to make it fit on a pole of some kind, would-it be upside 
up or down?  If down, this would be a good indication that both 
boba-fett's and my hypothesis would be good, no?

I, Bob, don't remember how it was tapered.

Colin Brewer said:

My hobby is visiting the stone circles and monoliths in Britain and I was 
fascinated by your Cong ... We now know that the stone monuments are not 
local to Western Europe and are found as far as Korea .. we also know that
the stone circles have acoustic properties and recent studies show that 
Stonehenge has acoustic properties caused by the inward-facing concave 
surfaces  - sorry I forgot the name of the book or the BBC programme .. I 
wonder if the right answer is that the Cong is a musical instrument maybe 
a drum.. has anyone tried building a model ? 

Pentagons that tile the plane
A good random number generator
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