we have all heard of ou muscial pillars , read this about the chinese in The Temple of Good Harvests
The "Temple" is actually a series of 3 separate structures laid out North to South. It was built in the early 1400s. It is approx 15 miles southeast of the Forbidden City.
The southern most part of the enclosed grounds (a red wall and blue tile roofs - representing earth & sky) is the "Round Altar". Below it is a crematory altar which offered up sacrifices to the Gods before the commencement of the ceremony which occurred only twice a year, in the springtime and at winter solstice. There are 8 round burning cauldrons representing the 8 Quing Emperors. Then the white marble Round Altar rises. This Round Altar is perhaps 75 yards in diameter. It rises 3 tiers symbolizing earth, man, and heaven. At the center of the top tier according to Chinese cosmology is the Center Stone. The Center Stone is said to mark the very center of the world, and thus the Emperor's voice would resonate to the Gods much more strongly here. Only the Emperor would pray while kneeling or standing on the Stone.
North of the Altar is the Imperial Vault of Heaven which housed the stone tablets upon which were inscribed the most holy prayers to the Gods. The courtyard around the vault contains an Echo Wall, a well designed circular wall again about 75 yards in diameter that allows people on opposite sides of the courtyard to talk easily to each other. On the steps leading to the vault - you take one step and clap - you hear one echo, take two steps and clap - you will hear two echos , take three steps and clap -you will hear three echos ( i saw this being demonstrated in discovery channel last night)