Oxford observatory is a most magnificent structure, 1.vorthy of the celebrity of that distinguished university. It was begun in the year 1772, from very ample funds bequeathed by Dr. Radcliffe, and upon a piece of land given for that purpose, by the Duke of AIarlborough. The transit instrument, which is ten feet long, shows very small stars in the day time, and is said to have cost 150 guineas. The zenith sector also is a fine instru - ment, and cost 200 guineas ; and there are two mural quadrants of 600 guineas value.
Herschel and Dollond have also furnished it with very admirable telescopes, and Skelton with a clock of ex cellent workmanship. It was built under the direction, of Dr. Hornsby, professor of Astronomy in the univer sity, who observed here for many years. He has been succeeded by Dr. Abram Robertson, the present wor thy Savilian professor of astronomy.
The observations are all registered, and consist chiefly of the right ascensions and zenith distances of the sun, moon, planets, and fixed stars. In Dr. Hornsby's time, the series of observations was sometimes broken off from ill health ; but as an assistant observer has been lately added, the observations will not, in future, be liable to interruption.
It has been proposed to erect a splendid observatory at Cambridge, every way worthy of that distinguished university ; and the necessary funds have, in a great measure, been provided for that purpose. The obser vatory syndicate, it appears, have reported to the senate of Cambridge, that the arrangements with St. John's College, for the site of the observatory, although not completed, are yet considerably advanced, and will pro bably be soon brought to a termination ; that Messrs. Munday and Bushell have entered into a contract with the syndics, by which they engage, before the end of October, 1823, to complete the buildings, faced with stone throughout, agreeably to Mr. AIead's plans and specifications, for the sum of 8497/. 88. 6d. The ex cavations and levelling of the ground for the new ob servatory have just commenced.
We have not been able to ascertain when such a va luable appendage to that university will be completed. It is only, however, by multiplying the places at which very accurate astronomical observations are made, that the science of astronomy can be now perfected, and we sincerely wish success to the completion of this useful undertaking.
The observatory at Slough, near Windsor, where Sir William Herschel observes, will for ever claim a place in the history of distinguished astronomical institutions.
In its plan and apparatus it differs from all other obser vatories, and exceeds them all in the number and im portance of its discoveries.
It may be remarked, in describing this observatory, that the labours of Sir William Herschel have a pecu liar interest, from the circumstance that his discoveries are all the result of his own inventions. For, to a pro found knowledge of astronomy, he adds that of optics in a very eminent degree, both in theory and practice, by which lie has been enabled to cast and polish mirrors for reflecting telescopes, greatly superior to any other, not only in magnifying power, but in collecting- or pre serving light, by which vision is wonderfully extended, and which he very expressivelv denominates " the power of penetrating into space." The telescopes, which are all madc under his direction, are of various sizes, from two to forty feet in length, and the apparatus and ma. chinery upon which thcy are mounted are also of his own contrivance, and exhibit a very ingenious display of mechanical invention.
As his larger instruments could not he conveniently mana,%d within the covcrof a huilding. they are-mounted in the open air, where they stand pointing to the hea vens in different directions, and make a most magnifi cent and impressive appearance.
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His largest telescope, forty feet long, and five feet in diameter, has been fully explained in our article OPTIcs, in this volume, and represented in Plate CCCCXLI. Two of his smaller telescopes will always be ramous the history of astronomical discovery. The first is a two feet Newtonian reflector, with which his sister, Miss Caroline Herschel, discovered six comets ; and the other is his seven feet reflector, with which he disco vered the Georgian planet, or Uranus, at Bath, in 1781. This telescope, in consequence of the discovery, has been made a constellation in the heavens, with the uni versal approbation of astronomers. It is placed between Gemini, the Lynx, and Auriga, and contains 81 stars. In Bode's Atlas it is engraved with its apparatus, and marked Telescopium Herschelii. Sir William Her schel is now in his eighty-fifurth year, and was born at Hanover, on the 15th of November, 1738, a period which will be ever memorable in the history of astro .