The Mirror of Literature, Amusement, and Instruction. Volume 14, No. 404, December 12, 1829. Various

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      In the present almanack season, as it is technically called, the above illustration of our pages may not be inappropriate or ill-timed, inasmuch as it represents the spot whence all English astronomers make their calculations.

      The Observatory was built by Charles II., in the year 1675—probably, observes a recent writer, "with no better motive than to imitate Louis XIV.," who had just completed the erection and endowment of an observatory at Paris. The English Observatory was fortunately placed under the direction of the celebrated Flamstead, whose name the hill, or site of the building, still retains. He was appointed astronomer-royal in 1676; but Charles (as in the case of the curious dial at Whitehall, described by us a few weeks since1), neglected to complete what he had so well begun: and Flamstead entered upon the duties of his appointment with instruments principally provided at his own expense, and that of a zealous patron of science, James Moore. It should seem that this species of parsimony is hereditary in the English Government, for, upon the authority of the Quarterly Review, we learn that "within the wide range of the British Islands there is only one observatory (Greenwich), and scarcely one supported by the Government. We say scarcely one, because we believe that some of the instruments in the observatory at Greenwich were purchased out of the private funds of the Royal Society of London."2

      The first stone of this Observatory was laid by Flamstead, on the 10th of August, 1675. It stands 160 feet above low-water mark, and principally consists of two separate buildings: the first contains three rooms on the ground-floor—viz. the transit-room, towards the east, the quadrant-room, towards the west, and the assistant's sitting and calculating-room, in the middle; above which is his bed-room, the latter being furnished with sliding shutters in the roof. In the transit-room is an eight-feet transit-instrument, with an axis of three feet, resting on two piers of stone: this was made by Bird, but has been much improved by Dolland, Troughton, and others. Near it is a curious transit-clock, made by Graham, but greatly improved by Earnshaw, who so simplified the train as to exclude two or three wheels, and also added cross-braces to the gridiron-pendulum, by which an error of a second per day, arising from its sudden starts, was corrected. The quadrant-room has a stone pier in the middle, running north and south, having on its east face a mural-quadrant, of eight feet radius, made by Bird, in 1749, by which observations are made on the southern quarter of the meridian, through an opening in the roof three feet wide, produced by means of two sliding shutters; on its west face is another eight-feet mural quadrant, with an iron frame, and an arch of brass, made by Graham, in 1725: this is applied to the north quarter of the meridian. In the same apartment is the famous zenith-sector, twelve feet in length, with which Dr. Bradley, at Wanstead, and at Kew, made those observations which led to the discovery of the aberration and nutation: here also is Dr. Hooke's reflecting telescope, and three telescopes by Harrison. On the south side of this room is a small building, for observing the eclipses of Jupiter's satellites, occultations, &c., with sliding shutters at the roof and sides, to view any portion of the hemisphere, from the prime verticle down to the southern horizon: this contains a forty-inch achromatic, by the inventor, Mr. John Dolland, with a triple object-glass, a most perfect instrument of its kind; and a five-feet achromatic, by John and Peter Dolland, his sons. Here, likewise, are a two-feet reflecting-telescope (the metals of which were ground by the Rev. Mr. Edwards), and a six-feet reflector, by Dr. Herschell.

      The lower part of the house serves merely for a habitation; but above is a large octagonal room, which, being now seldom wanted for astronomical purposes, is used as a repository for such instruments as are too large to be generally employed in the apartments first described, or for old instruments, which modern improvements have superseded. Among the former is a most excellent ten-feet achromatic, by the present Mr. Dolland, and a six-feet reflector, by Short, with a clock to be used with them. In the latter class, besides many curious and original articles, which are deposited in boxes and cupboards, is the first transit instrument that was, probably, ever made, having the telescope near one end of the axis; and two long telescopes with square wooden tubes, of very ancient date. Here, likewise, is the library, which is stored with scarce and curious old astronomical works, including Dr. Halley's original observations, and Captain Cook's Journals. Good busts of Flamstead and Newton, on pedestals, ornament this apartment; and in one corner is a dark narrow staircase, leading to the leads above, whence the prospect is uncommonly grand; and to render the pleasure more complete, there is, in the western turret, a camera obscura, of unrivalled excellence, by which all the surrounding objects, both movable and immovable, are beautifully represented in their own natural colours, on a concave table of plaster of Paris, about three feet in diameter.

      On the north side of the Observatory are two small buildings, covered with hemispherical sliding domes, in each of which is an equatorial sector, made by Sisson, and a clock, by Arnold, with a three-barred pendulum, which are seldom used but for observing comets. The celebrated Dry-well, which was made to observe the earth's annual parallax, and for seeing the stars in the day-time, is situated near the south-east corner of the garden, behind the Observatory, but has been arched over, the great improvements in telescopes having long rendered it unnecesary. It contains a stone staircase, winding from the top to the bottom.

      The Rev. John Flamstead, Dr. Halley, Dr. Bradley, Dr. Bliss, Dr. Nev. Maskelyne, and John Pond, Esq. have been the successive astronomers-royal since the foundation of this edifice.

      TWIN SISTERS

      (For the Mirror.)

      The most extraordinary instance of this kind on record is that of the united twins, born at Saxony, in Hungary, in 1701; and publicly exhibited in many parts of Europe, among others in England, and living till 1723. They were joined at the back, below the loins, and had their faces and bodies placed half side-ways towards each other. They were not equally strong nor well made, and the most powerful, (for they had separate wills) dragged the other after her, when she wanted to go any where. At six years, one had a paralytic affection of the left side, which left her much weaker than the other. There was a great difference in their functions and health. They had different temperaments; when one was asleep the other was often awake; one had a desire for food when the other had not, &c. They had the small pox and measles at one and the same time, but other disorders separately. Judith was often convulsed, while Helen remained free from indisposition; one of them had a catarrh and a cholic, while the other was well. Their intellectual powers were different; they were brisk, merry, and well bred; they could read, write, and sing, very prettily; could speak several languages, as Hungarian, German, French, and English. They died together, and were buried in the Convent of the Nuns of St. Ursula, at Presburgh.

      P.T.W.

      ELEGY ON THE DEATH OF A SPARROW

      (For the Mirror.)