|Author:||Probably James Glaisher, Superintendent of the Magnetic Observatory at Greenwich|
|Title:||The Royal Observatory|
|About:||This account was published on 1 July 1858 under the title of The Royal Observatory in the first ever edition of The Stereoscopic Magazine, (Lovell Reeve, London). The Stereoscopic Magazine was published monthly between July 1858 and February 1865 with each issue usually containing 3 stereoviews. Those of the first edition at least, were produced under the superintendence of James Glaisher, who had developed his photographic expertise during the course of his work at the Observatory. Whilst copies of the stereoviews are rare, preserved copies of the accompanying text are rarer still. Glaisher's account contains what is probabaly a unique description of the shrub plantings in the Observatory Courtyard. The stereoview of the Observatory exists in at least three (and probably more) different versions. This is because at that time, the printing process needed lengthy daylight exposures limiting production to perhaps just half a dozen prints per day from each set of plates. If he didn’t take them himself, it is likely, that Glaisher was present when the photographs were taken.|
THE ROYAL OBSERVATORY
THE accompanying stereoscopic vignette represents the well-known exterior of Greenwich Observatory, looking towards the north front. Our selection of this view in preference to that more frequently chosen, which includes the entrance-gates and magnetic clock, has been influenced by the picturesque character of this portion of the building, which, with little difference, is the original Observatory as founded by Charles II, and generally known as Flamsteed House. It also exhibits a part of the elevation on which the Observatory stands, sloping downwards to the north by a somewhat sharp declivity towards the Thames. To the right are just visible the topmost boughs of a Scotch pine, one of a phalanx which flank the slope on either side, and not improbably in former times marked the steep approach to the old tower which was pulled down two centuries ago that the Observatory might be founded upon its site. If we except the time-ball and the anemometer vane surmounting the turrets on the roof, and the domes on either side the main body of the edifice, we see in the stereograph the Observatory nearly as designed by Sir Christopher Wren, and presided over by Flamsteed, the first Astronomer Royal. The portion of the surrounding wall between the side wings and that which encloses the west front is, it is more than probable, of a date anterior to the rest of the building.
In the year 1457, the park in which the Observatory is situated was enclosed, and there exists a curious charter dated March 26, 1437, in the reign of Henry VI., which conveys 200 acres of the Manor of East Greenwich, then an unenclosed waste, to Humphrey, Duke of Gloucester, and to Eleanor, his wife. The old tower occupied the summit of the hill on which the Observatory is situated, and in the year 1526 it was repaired or rebuilt by Henry VIII., who visited "a fayre ladye whom he loved here."
Mary, daughter of Edward IV., betrothed to the King of Demark, died at the tower in Greenwich Park in 1482. In Queen Elizabeth’s time it was called "Mirefleur.” In 1642 it was called Greenwich Castle, and thought of so much consequence as a place of strength that immediate steps were ordered to be taken for securing it ; but in 1675, after the Restoration, the old tower was pulled down and the Royal Observatory was founded upon its site. It is supposed that the foundations of the tower still remain, and that part of the outer wall, modernized and heightened, helps to enclose the modern building on its north and west sides.
The Observatory may be said to have originated from the extension of navigation in the sixteenth and seventeenth centuries, but the immediate cause of its erection arose out of a remark made in the King's presence respecting the great importance of possessing means of accurately determining the longitude of a ship at sea. It was remarked that this could be effected provided that the motion of the moon among the stars could be exactly predicted before a ship left England; for then, if at any part of the voyage the navigators should observe the moon in a situation with regard to the fixed stars, the precise London time could be found from that observed situation. The matter was referred to a Commission of scientific men, and by them to John Flamsteed, of Derby, then known for his knowledge And love of astronomy. Flamsteed stated that he considered the lunar tables, and the places of the stars, in catalogues, not determined with sufficient accuracy to make the plan practicable. On hearing this the King resolved upon the cultivation of astronomy as art object of national importance, and in the same year the building of the Observatory was commenced.
Flamsteed was appointed Astronomer Royal, through the interest of Sir Jonas Moore, Surveyor-General of the Ordnance, and mathematical tutor to James, Duke of York. Two years later he entered upon the duties of his office. The only instruments he could obtain possession of were an iron sextant of seven feet radius, two clocks given to him by Sir Jonas Moore, together with a quadrant of three feet radius and two telescopes which he brought with him from Derby; yet with these and some others which he subsequently caused to be constructed at his own expense, first by entering upon the duties of a teacher, and later in life by the devotion of the means left to him by his father, and accruing to him from other sources, he succeeded in laying the foundation of modern astronomy. Up to this time the catalogue of Tycho Brahé had been the only guide to astronomers, and was highly imperfect, having been formed without the aid of a telescope, which was not then invented. To an improved catalogue Flamsteed at once directed his attention, and the invention of the telescope, united to the introduction of the clock, then first used for astronomical observations, greatly assisted him in carrying his plan into effect.
Flamsteed died in 1719, and the publication of the 'Historia Celestis,’ which contains the accumulated results of his official labours, did not appear in a complete form until some time after his death. During his appointment, under the reign of Queen Anne, the Board of Visitation, consisting of the President and Council of the Royal Society, was instituted for the purpose of inquiring into the work performed at the Observatory, the condition of instruments, etc., and to receive a report of progress made during the year. The custom has been continued annually since, and is an anniversary looked forward to with mutual satisfaction by all parties concerned.
On the death of Flamsteed, Halley was appointed to the vacant office. It was two years before the instruments provided for him by Government were in working order. All Flamsteed’s instruments bad been removed as private property, Government having attempted to establish a claim upon them and upon his observations. To Halley succeeded Dr. Bradley, celebrated for his discovery of the aberration of light previously to his appointment, and for his other celebrated discovery of the nutation of the earth's axis, completed after he had been a few years at Greenwich. To Bradley succeeded Bliss, who died after holding his appointment three years, and in 1765 Dr. Maskelyne was appointed.
The history of the Observatory during all this time was one of progress. The instruments provided for Halley, a transit instrument, and an eight-feet mural quadrant, were retained for the Observatory, and others added in the time of his successors. New buildings, to provide them with suitable accommodation, were appended to the original structure, and when Dr. Maskelyne commenced his astronomical career, destined, like that of Flamsteed, to continue for nearly half a century, he found himself in a better position with regard to instruments and appliances than any of his predecessors. He devoted his time entirely to the duties of his office, and left so fine a series of observations, the labours of his life, that it has been said if, by some catastrophe, the whole materials of science should be lost except these volumes, they would suffice to reconstruct the edifice of modern astronomy. Of the large mass of observations made by this amiable and persevering astronomer, those made with reference to the correction of the lunar tables are among the most valuable that had been recorded, and up to that time were without parallel. Before his death he ordered the great meridian circle constructed by Troughton, the idea of which was suggested by a smaller instrument of the same kind in the possession of Mr. Pond, and known as the Westbury Circle. He died in 1811, before the instrument was completed. We may add that Maskelyne’s observations were chiefly made with the instruments used by Bradley, and constructed for him by Bird, out of a suns of £1000 granted by George II. for that purpose, the quadrant and transit instrument being supplied with new object-glasses.
Pond succeeded to the office of Astronomer Royal on the death of Maskelyne. Shortly after his appointment a new transit instrument was mounted, and in 1812 the great meridian circle ordered by his predecessor. After the lapse of a few years he was provided with a second mural circle, constructed by Jones. Pond was known long before his appointment for his love of astronomical pursuits, and had already published determinations of the places of the fixed stars, equal if not superior to those determined by public observatories, the Westbury circle, a small instrument three feet in diameter, being employed by him in these determinations. On taking up his residence at Greenwich, Pond turned his attention to the best methods of observing, which has since entitled him to be considered the principal improver of modern practical astronomy. He left a large maw of valuable observations, a catalogue of more than 1100 stars, and a continuous series of observations of the sun, moon, and planets, besides greatly multiplying observations of the principal stars. He resigned his office in 1835, harassed with anxieties, and suffering at the time from infirm health. He died in the year following, at his residence in the vicinity of the Observatory. In Mr. Pond's time the number of assistants was increased from one to six.
The present Astronomer Royal, G. B. Airy, Esq., was appointed in the year of Pond's resignation. During the quarter of a century which has since nearly elapsed, the operations of the Observatory have been greatly extended. To the regular series of observations, and to the calculations requisite to be performed for their reduction, the subjects Of Magnetism and meteorology have of late years been added. In Bradley's time commenced the series of observations, considered properly characteristic of the Observatory, and which consists of observations of the stars, sun, moon, and planets, as they pass the meridian at whatever hour of the day or night, the observations being performed by Bradley, with transit instrument and clock, for the determination of right ascension, and by the quadrant for the determination of North Polar distances. Since then the mural circle has superseded tho quadrant, and other instruments of compound and improved construction have been added to those in use at the Observatory by the present Astronomer Royal, but the same class of observations, and the same method and continuity in recording them is, we may add, preserved now as heretofore. The magnetic and meteorological department, established about sixteen years ago, adjoins that of the astronomical, its records being assisted by the new science of photography. If it were within the limits and the aim of the present article, we might enter upon on account of the instruments in use, and the system of observation employed in both departments at the present time, with interest and possible benefit to our renders. As compared with the preceding rate of advance, the details of progress there exhibited would be of no ordinary interest, and would be found to include much beyond those immediately applying to the theory and practice of astronomy.
It yet remains to speak of the stereograph, which, as we have already mentioned, represents the Observatory but little altered since Flamsteed’s time. On the basement story are just visible the windows of the range of apartments belonging to Flamsteed, and immediately above is the great octagon room, intended for the use of the larger instruments, telescopes, quadrants, etc., but now entirely disused for all such purposes. The three windows and balcony of this fine room, overlooking the steep footpath approach to the Observatory, is a distinguishing feature in every view of the north front. The two wings, one on either side, in Flamsteed’s time were summer-houses, and not connected, as at present, with the Observatory. About the year 1770 these wings or summer-houses were covered with revolving domes, and connecting staircases with the Observatory were added at the same time; they were occupied by an equatorial sector, which was transferred occasionally from the one wing to the other, as was found necessary in use. On the top of the octagon room, over the north-west angle, is a turret for carrying Osler's anemometer. The north-east angle is occupied by the turret surmounted by the time-signal ball, the object of which is to give notice to the Navy of the exact time, by dropping it from the cross which surmounts the staff, at the precise instant of one o'clock. The ball is five feet in diameter, is hollow, and constructed of wood, covered with black leather, and is made to ascend and descend vertically, at the appointed time, upon a shaft, surmounted by a black cross and vane. It is wound up daily to its highest position by winch, situated in one of the lower rooms of the Observatory, a few minutes before one o'clock. At the precise hour of one the ball is made to descend, and the instant of its separation from the cross gives the true Greenwich time. The liberation of the ball is performed in a room beneath the winch by means of a galvanic current in connection with the clock, the error and rate of which is accurately determined. To prevent the ball, when liberated, from descending with a shock upon the roof, and thus giving a rebound, it is allowed to fall by its own weight on being first detached, but is connected with a piston working in a cylinder; which thus breaks the fall, and causes, as our readers will often have remarked, its leisurely descent on approaching within a little distance to the lower end of the staff. The time-ball was put up during Pond's residence at Greenwich, as it became more than ever desirable have a ready means of making the true time extensively known, not only to the Navy, but to all the shipping collected in the river and port of London.
The adjoining turret is occupied by an Osler's self-registering anemometer, by which the direction of the wind, and its pressure in pounds on a square foot, are constantly recorded by two pencils acting on a sheet of paper, divided into Hour-spaces, and driven by a clock. The vane in connection with it, which surmounts the turret, is nine feet in length, and is a conspicuous and picturesque object in the photograph. By its side, at a lower elevation, is visible Osler's self-registering rain-gauge. These turrets date probably from the foundation of the Observatory, and are in perfect harmony with the original design. On the east side, to the left of the dome, will be perceived a staircase, leading outside the walls of the great octagon room to the roof, and serves as a way of approach to the anemometer turret. The staircase is a recent addition, put up by the present Astronomer Royal, the former approach being by a staircase withinside to the roof, so that the privacy of the great room, no longer employed for the official work of the Observatory, may not be interfered with by the periodical visits of the assistant in charge of the recorded readings of the instrument.
The low range of buildings of more recent date, which, commenced in Bradley's time, have been receiving constant additions since, and really constitute the Observatory of the present day, is not visible at any part in the stereograph. The wall leading on from the north-east dome, towards the entrance-gates, encloses the front court, across which the visitor, on gaining admittance, makes his way to the entrance of the private dwelling-house of the Astronomer Royal. A part of the front court, which consists of made ground, was formed, it is supposed, during the existence of the old tower or castle. At present it is a well-kept level of gravel, bordered on the aide adjacent to the railings by flowering shrubs and trees. The effect of these, on entering the secluded precincts of the. Observatory, is eminently agreeable, and the laburnums; lilacs, and rich crimson beech, the latter of which is the picturesque foliage by the side of the north-east dome, are graceful heir-looms which the present proprietors have not failed to appreciate and encourage to the utmost; and truly pleasant it is to see how the more delicate of our forest-trees, mingling with the broom, guelder-rose, and maythorn, and many more than we should care to name, have been permitted to share the enclosure devoted to the appliances of modern science, and how that their cheerful presence lends a charm to the discharge of the monotonous routine of daily duty. The visitor, as he passes along the north terrace, the iron rails of which are visible in the photograph, and continues his walk past the east wall, beyond the entrance-gates, and onwards by the fencing of the magnetic enclosure, will, if he pause before an open gate, or stop to overlook the fencing, be struck with the heterogeneous collection of temporary, habitations for instruments and apparatus, offices for workmen, etc., grouped in picturesque confusion, and all embosomed in a luxuriant but wild garden, frequented, as some well know, by many sorts of birds, which, in the retirement thus afforded them, build their nests, and return year by year, fearless of the near vicinity of the little corps of observers, between whom and themselves has long existed a reciprocal feeling of regard and protection; and whilst ho looks, the contrast will strike him forcibly which exists between the heavy, castellated building of red brick and stone, presided over by Flamsteed, enclosed by the high retaining wall of the old fortress, and which had to be furnished out of the slender means of the persevering and enthusiastic astronomer, and the temporary wooden huts, under which are sheltered the costly and multifarious instruments and other appliances which modern ingenuity, aided by recent enterprise, discovery, and research, have enabled the present Astronomer Royal, with the full assistance, of Government, to assemble, in one department alone of the National Observatory.