PEOPLE'S REPUBLIC OF CHINA
COINS OF INVENTION AND DISCOVERY IN ANCIENT CHINA - SERIES ONE - THE FIRST SEISMOGRAPH
RARE GOLD ONE-HUNDRED YUAN COIN
CERTIFIED BY NGC PROOF 69 ULTRA CAMEO
OBV: SECTION OF THE GREAT WALL OF CHINA WITH TWO TOWERS; DATE BELOW.
REV: HAN DYNASTY (206 BCE-220 CE) ORNATE BRONZE "EARTHQUAKE WEATHERCLOCK" OR "EARTHQUAKE DETECTOR" BUILT BY ASTRONOMER AND MATHEMETICIAN CHANG HENG IN 132 AD; BOTTOM LEFT THREE CHINESE SCHOLARS STANDING ON A PARAPET WITH THE CENTER FIGURE POINTING WITH OUTSTRETCHED LEFT ARM; DENOMINATION BELOW.
KM # 416
ZHANG HENG (CHANG HENG) (78-139 C.E.) WAS AN INVENTOR, MATHEMETICIAN, ASTRONOMER, CARTOGRAPHER, POET, STATESMAN AND SCHOLAR DURING THE HAN DYNASTY. HE IS CREDITED WITH INVENTING THE WORLD'S FIRST SEISMOMETER (SEISMOGRAPH OR SEISMOSCOPE) AND FIRST WATER POWERED ARMILLARY SPHERE. THE SEISMOSCOPE WAS CALLED THE HOUFENG DIDONG YI "INSTRUMENT FOR MEASURING THE SEASONAL WINDS AND THE MOVEMENTS OF THE EARTH". IT WAS A 2 METER DIAMETER BRONZE VESSEL WITH EIGHT DRAGONS AROUND THE TOP WHOSE HEADS HELD BRONZE BALLS. WHEN THERE WAS AN EARTHQUAKE, ONE OF THE DRAGON'S MOUTHS WOULD RELEASE THE BALLS WHICH WOULD DROP INTO THE GAPING MOUTH OF ONE OF THE 8 BRONZE TOADS SURROUNDING THE VESSEL'S BASE. THE BALL THAT DROPPED WOULD INDICATE THE DIRECTION OF THE QUAKE. IN 143 CE, A LARGE EARTHQUAKE IN GANSU, WHICH WAS NOT FELT AT THE TIME, CAUSED A BALL TO DROP.
CONTAINS 31.1035 GRAMS OF .999 FINE GOLD (1 OZ AGW)
32 MM IN DIAMETER
ONLY 1,000 MINTED!