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English: John Thomson: LATHER LE COMTE visited the Peking Observatory in 1688, just after the death of Father Verbiest, under whose directions the new instruments had been constructed there. Le Corate seems to have formed but a poor estimate of the ancient Chinese instruments, which had been already removed and stored in an obscure hall, in a court below the wall. He describes them as buried in dust and oblivion, but he only saw them "through a window close set with iron bars."

Among those rejected instruments was the one I have here shown, and which has since been set up at one end of the court I have no doubt had this devoted missionary seen it, even in its present condition, he would have arrived at a much higher appreciation of the beauty and comparative finish of its workmanship.

The old Chinese astronomical instruments, although constructed with an amazing degree of skill and exactness, would now be perfectly useless; for the mode of taking astronomical observations at that time was widely different from the system in use at present, besides which the circles are inaccurately divided.

The instruments, constructed under the superintendence of Father Verbiest, do not show so marked a superiority over those of the Chinese astronomers as I had expected. They are undoubtedly finer and more accurate; but they too were constructed by Chinese artificers, and Le Comte says of them, " 1 would rather trust to a quadrant made by one of our good workmen in Paris, whose radius should be but one foot and a-half, than to that of s.x feet, which is at this tower." The divisions of the circles, though more accurate than those of the old instruments, are still defective.

I have in my possession a Chinese narrative wherein Verbiest describes the rude appliances w.th which he had to work, and my only surprise is that he should ever have been able to construct instruments such as those wh.ch I have pictured in No. 10. We are shown in the volume referred to, how the castings of the great circles appeared in the rough; how they were sawn into shape; and how finally they were turned upon a horizontal lathe made like an ordinary Chinese flour mill, with a donkey to drive it. It pictures, in addition, the mode in which the celestial globe was turned. This globe was simply laid into its frame, upon an axis having one extremity fitted with a handle, like that of a large circular grindstone. Motion was next imparted to the globe from this handle, and from the' feet of an operator treading upon the upper surface of the metal sphere, while the hand of an operator was used to steady the turning tool in order to dress the metal, and render it perfectly globose and true on its axis. All the appliances are of the same primitive sort. The dividing of the circles must have been done by hand in some open shed; whereas in Europe, at the present time, we find it necessary, when an important circle is to be divided, to have the dividing engine built upon a rock and enclosed in a chamber where the temperature is kept uniform until the process of dividing the circle has been completed. By this device we avoid contractions and expansions of the metal circle, which would otherwise mar the perfect accuracy of the divisions.

The globe is described by Le Comte as follows—"^ Celestial Globe. This in my opinion is the fairest and best fashioned of all the instruments. The globe itself is brazen, exactly round and smooth; the stars well made, and in their true places, and all the circles of a proportionate breadth and thickness. It is besides so well hung that the least touch moves it, and though it is above 2,000 lbs. weight the least child may elevate it to any degree." This globe, seen on the left of the illustration (No. to), is still in a perfect state of preservation, although it has been exposed in the open air without covering for full two centuries. The stars on this celestial globe are all raised brass, and distinguished according to their magnitude, for the convenience of feeling on a dark night. The old Chinese method of division is abandoned on these instruments, the circle being divided into 360", and each degree into sixty minutes, as in Europe.

Armillary sphere on the terrace of the Observatory at Peking, No. 10. This is also one of the instruments made under the directions of Father Verbiest. The circles are divided, both in their exterior and interior, by cross lines into 360", and each degree into 60 minutes, and the latter into portions of 10 seconds each by small pins.

I am greatly indebted to Mr. A. Wylie for valuable information regarding the Observatory and other places of

interest in Peking.