end of the thirteenth century, Ko-show-king, one of the most renowned astronomers in Chinese history, being chief of the astronomical board at the time. The instrument shown at No. i [, constructed under his directions, now stands below the wall at the east end of the court. It is of huge dimensions, cast in solid bronze, and is of the most beautiful workmanship. The stand of this piece of mechanism has a mythological significance, and its design is of remarkable artistic excellence. Four of the dragons, which play such an important part in Chinese geomancy, are there seen chained to the earth, and upholding the spheres. The perfect modelling and solidity of the metal proves that the art of casting was well understood in those days.
A substantial metal horizon, crossed at right angles by a double ring for an azimuth circle, forms the outer framework. The upper surface of this horizon is divided into twelve equal parts, marked respectively by the cyclical characters, " tsze, chow, yin, maou, chin, szi, woo, wei, shin, yu, seih, hae," being the names applied to the twelve hours into which the Chinese divide their day and night.
Round the outside of the ring these twelve characters appear again, paired with eight characters of the denary cycle, and four of the "book of changes,'" designating the points of the compass, thus, "jin-tsze, kwei-chow, kan-yin, kea-maou, yih-chin, seuen-szc, ping-woo, ting-wei, kwan-shin, kang-yu, sin-seih, keen-hae."
The inside of the ring bears the names of the twelve states into which China was anciently divided : every part of the empire being supposed to be under the influence of a particular quarter of the heavens.
An equatorial circle is fixed inside this frame, within which a movable series of rings turns on two pivots at the poles of the azimuth circle. The latter consists of an equatorial circle, and a double ring ecliptic, an equinoctial colure, and a double ring solstitial colure. The equator is divided into twenty-eight unequal portions, marked by the names of so many constellations of unknown antiquity. These are, " keo, kang, te, fang," &c. &c.
The determinant points of each of these constellations are used for so many meridian lines, from which all distances are measured, just as we use the vernal equinox for right ascension.
The ecliptic is divided into twenty-four equal parts, into which the year is portioned out. Inside this, again, there is a double revolving meridian, with a double axis; and in it a tube is fixed, turning on a centre, for taking sights.
All these circles are also divided into 365^° corresponding to the days of the year, and each degree is subdivided into a hundred equal parts; for at that time the centenary division prevailed for everything less than degrees, and was only abandoned on the arrival of the Jesuit missionaries in the seventeenth century.
At the corners of the base, and outside the dragons, are four miniature rocks in bronze, with the respective inscriptions, "keen shan, north-west or celestial mountain; kwan shan, south-west or terrestrial mountain; seuen shan, or south-east mountain; kan shan, north-east mountain."
These are probably symbolical in reference to an old tradition.
Note. — Owing to the difficulty or procuring the Chinese cyclical and other characters in England, I have given the sounds of the characters
in English.
