The Chinese boast of their having made a very early progress in astronomy, both in theory and practice, but their accounts are to be received with much caution. In Hindostan, too, traditions relative to, and vestiges of, ancient observatories, on which ingenious disquisitions have becn written, are said to abound. About 260 years ago, five different observatories were constructed by the Hindoos under the reign of the Emperor Mahommcd Shah, with a view to reform the calendar by means of astronomical observations ; for the accomplishment of ' which, Jcysing, or Jayasinha, Rajah of Ambhere, was chosen chief astronomer. These observatories were built at Delhi, Benares, Matra, 0 ujein, and Suvai Jcypoor, and all under the direction of Jeysing. The observatory of I3enares will be fully described in a succeeding palt of this article, and as all the others were built and furnish ed on the same plan, the description of one will be suf ficient to give a tolerably clear idea of the whole.
The Chinese erected an imperial observatory at Pe kin, on the city walls, in the thirteenth century ; and, in 1668, Father Verbiest, a missionary Jesuit, having been made president of the tribunal of mathematics, and chief observer, obtained permission from the Emperor Cain-hi to furnish it 1% ith proper instruments.
Other observatories were afterwards built in China by the French missionaries, and by the Portuguese Jesuits, who distinguished themselves very much by their la bours and improvements in astronomy. The instru ments of the Pekin observatory are said to be very large, but the divisions less accurate, and the construction less commodious, than those of the instruments made at that time in Europe. The chief instruments of the Pekin observatory consisted of a sextant eight feet radius, a quadrant six feet radius, an azimuthal horizon, a celestial globe, and an armillary sphere, each six feet in dia meter.
The celebrated Copernicus, about 1540, is said to have been the first.European who set an instrument in the meridian, though the first regular observatory was erected at Cassel in 1561, by William, Landgrave of Hesse, who furnished it with the best instruments that the age could produce. Here, it is said, he made very accurate observations, in conjunction with his friend and correspondent Tycho Brahe, then rising into fame. The next observatory in Europe, which deserves particular notice, was that of Tycho Brahe himself. It owed its origin, it is said, to the appearance of a new star of the first magnitude in the constellation Cassiopeia. Tycho l3rah6 was so iinpressed with the appearance of this ex traordinary phenomenon, that he formed the resolution of making a new and accurate catalogue of all the stars, as there had becn nothing of the kind done since the time of Ilipparchus, who had been stimulated to the same undertaking by a similar cause.
For this purpose, Tycho Brabe proposed to settle at Basle, which had a pure atmosphere, and afforded a ready communication with the learned men of Germany, France, and Italy. But thc Landgravc of Hesse wrote to Frederick II. king of Denmark, entreating him to
encourage the astronomer to remain in his own country. In consequence of this application, the king assigned to him the small but fruitful island of Iluen, in the Sound, as a fit situation for an observatory, and conferted on him other favours. His majesty, besides, undertook to defray the expenses of building and furnishing the ob servatory, with a munificence which has immortalized his name. The first stone of the observatory was laid on the 8th of August, 1576, and the place was called Urani burg. It consisted of a building of sixty feet square, and seventy feet high, with four towers, all adapted to astronomical purposes.
It was furnished with a valuable collection of instru ments, many of which were invented by the astronomer himself. He had numerous assistants, whom he sup ported and instructed. Among his instruments was a celestial globe of six feet diameter, said to have cost one thousand pounds. It was after his death carried to Prague ; afterwards to Neis ; and lastly, to Copenhagen, where it was burnt in the great conflagration of 1728. Many of the instruments of this great astronomer were long carefully preserved, but have been gradually lost; and his favourite residence Uraniburg, which in his time was visited by kings and princes, has been long a heap of ruins, so that its corrcct situation is but imperfectly known. Relative to this place, Delambre has written an interesting memoir in the Connaissance dcs Terns, for 1816.
Ilis celebrated sextant has been consecrated in the heavens as a constellation, under the breast of the lion. On large globes and atlasses, it is marked Sextans Uranirt, but on common ones Sextans.
_English Observatories.
The royal observatory at Greenwich, frotn the im portance of the observations and discoveries made there, claims our first attention. It was built and endowed by king Charles II. Ns-ho, as Bailly observes, knew well how essential a knowledge of astronomy was to a maritime and connnercial people. It Ivas erected on the site of the ancient moated tower of Duke Humphrey, the un cle of Henry VI. and the first stone of it was laid on the 10th of August, 1675, by Mr. Flamsteed, who had bcen appointed astronomer-royal. The words of his commission were, " To apply himself with the utmost care and diligence to the rectifying the tables of the motions of the heavens, and the places of the fixed stars, in order to find the so much desired longitude at sea, for perfecting the art of navigation." Every scientific navigator knows with what success this commission has been fulfilled by the labours oY each succeeding astro nomer-royal. It is situated on the highest part of Greenwich Park, at about 160 feet above low water mark, where the soil is peculiarly favourable for such an institution, being of a flinty gravel, through which the rain readily passes, thereby rendering the atmos phere generally dry, which contributes very much to the preservation of the instruments, as WCii as to the unifmnity of the refraction.