Old and New London: Volume 6. Originally published by Cassell, Petter & Galpin, London, 1878.
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GREENWICH (continued).—THE PARK, THE ROYAL OBSERVATORY, &c.
"Heavens! what a goodly prospect spreads around
Of hills, and dales, and woods, and lawns, and spires,
And glittering towns, and gilded streams, till all
The stretching landscape into smoke decays."—Thomson.
May-day Morning in the Reign of Henry VIII.—Historical Reminiscences—The Planting of the Park by Order of Charles II.—Castle Hill—Description of the Park—One-Tree Hill—Proposed Monumental Trophy in honour of the Battle of Trafalgar on Castle Hill—The View from One-Tree Hill—Greenwich Park at Fair-time—The Wilderness—The Ranger's Lodge—The Princess Sophia of Gloucester a Resident at Montagu House—Chesterfield Walk—The Residence of General Wolfe—Ancient Barrows or Tumuli—Greenwich Observatory—Appointment of John Flamsteed as First Astronomer-Royal—Flamsteed and Sir Isaac Newton—Dr. Halley—Dr. Bradley—Dr. Bliss—Dr. Maskelyne—The "Nautical Almanack"—Mr. John Pond—Sir George Biddell Airy—Description of the Observatory and of the Instruments in Use—The Magnetic Observatory—The Galvanic Clock—Work accomplished at the Observatory.
It was, no doubt, the peculiar charm of this unrivalled prospect that made Greenwich for so many ages the favourite seat of our Tudor monarchs, to whose purposes it was excellently adapted, both for its vicinity to the metropolis and its commanding situation. But far different must have been the scene when (we are told) Henry VIII., in the seventh year of his reign, on a fine May-day morning, with Queen Katharine his wife, accompanied also by many lords and ladies, rode a-Maying from Greenwich to the high ground of Shooter's Hill, where, as they passed by the way, they espied a company of tall yeomen all in green, with hoods, and with bows and arrows, to the number of two hundred. Since that day, alterations have taken place which must astonish even the last generation, large tracts of land, which then were either marketgardens or pastures for cattle, being now converted into docks or built over as streets.
"Let us pause," writes Mr. T. Miller, in his "Picturesque Sketches of London," "on the brow of this hill, and recall a few of the scenes which these aged hawthorns have looked upon. They are the ancient foresters of the chase, and many of them have stood here through the wintry storms of past centuries, and were gnarled, and knotted, and stricken with age, long before Evelyn planned and planted those noble rows of chestnuts and elms. Below, between the plain at the foot of the hill and the river, stood the old palace of Greenwich, in which Henry VIII. held his revels, and where Edward VI., the boy-king, breathed his last. That ancient palace was, no doubt, rich with the spoils of many a plundered abbey and ruined monastery—in vessels of gold and silver which had once been dedicated to holy purposes, but were then red with the dregs of the wine shed at many a midnight revel by the 'Defender of the Faith'—the woman-murdering monarch. Perhaps," he suggests, with a vein of dry humour, "the walls of that old palace were hung with the portraits of the wives whom he had caused to be beheaded, whilst his own likeness in the centre gazed, like a tiger, out of the frame upon his prey. On this hill, again, Cardinal Wolsey may have meditated, 'with all his blushing honours thick upon him.' Katharine, the brokenhearted queen, may here have reined-in her palfrey, or from this aged hawthorn have torn off a sprig, when fragrant and white with may-blossom, as now, and have presented it with a smile to the royal savage who rode beside her. On yonder plain, where so many happy faces are now seen, in former days the tournament was held. There gaudy galleries were erected, over which youth and beauty leant as they waved their embroidered scarves. We can almost fancy that we can see the crowned tiger smile as he closes the visor of his helmet, bowing his plume while he recognises some fair face which was soon to fall on the scaffold, with its long tresses dabbled in blood. . . . . In this park the crafty Cecil mused, doubtless, for many an hour, as he plotted the return of the Princess Mary, while the ink was scarcely dry in which he had recorded his allegiance to the Lady Jane Grey. In fact, the whole scenery of the park teems with the remembrance of old stirring events and grave historical associations. Hal, the royal murderer, comes straddling and blowing up the hill; the pale and sickly boy-king rides gently by, and breathes heavily as he inhales the sweet air on the summit; the titter and merry laugh of the illstarred queens seems to fall upon the ear from behind the trees that conceal them. And then we have voices of mourning and loud lament from fair attendants, who refuse to be comforted, for those whom they loved and served are there no more." This, we may add, is a very pretty and poetical picture, but none the less true for all that.
This park is the same as that previously mentioned (fn. 1) as having been enclosed by Humphrey, Duke of Gloucester, in 1433, by licence of King Henry VI. It contains nearly 200 acres, and was walled round by James I. Here, as in Kensington Gardens, we find the umbrageous trees that were planted by Gilpin and Le Notre, and the gardeners of William III. It was chiefly laid out by Le Notre, about the same time as St. James's Park, by order of Charles II., who, it is recorded, watched with great eagerness the work of laying out this park. As early as the spring of 1662, Pepys records that, "The king hath planted trees and made steps in the hill up to the castle, which is very magnificent." The "castle" here referred to was a tower erected by Duke Humphrey, on the site now occupied by the Observatory. Traces of Le Notre's "steps" or terraces are still observable in the hill-side leading to it. Castle Hill, it would seem, was at one time used as a "butt" or target for military practice; at all events, Evelyn, in his "Diary," under date of June 1, 1667, writes: "I went to Greenewich, where his Majesty was trying divers granados shot out of cannon at the Castle Hill from the house in the park; they brake not till they hit the mark; the forg'd ones brake not at all, but the cast ones very well. The inventor was a German." Of the time when the chief avenues were planted we get the exact date from the following entry in Evelyn's "Diary," where, under date of March 4, 1664, he writes: "This Spring I planted the Home-field and West-field about Saye's Court with elmes, being the same yeare that the elmes were planted by his Majesty in Greenewich Park." Now, however, except in the remains of some of the avenues, there are not very strong traces of the stiff and formal style of Le Notre left, as it is not on a beautifully-varied surface like this that straight walks and regular lines of trees are at all tolerable. The natural advantages of this park are certainly superior to those of any in the immediate vicinity of the metropolis. "The ground itself," says the author of "Bohn's Pictorial Handbook of London," "is undulated with great variety, sometimes being thrown up into the softest swells, and in other places assuming a bolder and more sudden elevation. Around the site of the Observatory it is particularly steep, and attains a considerable height. Everywhere, too, it is studded with noble specimens of ancient trees; and in this respect there are none of the other London parks at all equal to it. Some of the best trees are Spanish chestnuts, and the largest are on the south side. Many of these are truly fine and venerable, and would command admiration even if found in the heart of a purely rural district. The elms, which are abundant, are likewise large and noble; and there are some picturesque Scotch firs in the neighbourhood of the Observatory. These last are old enough to show the peculiar warm reddish colouring of the stems, and the characteristic horizontal or tufted heads. In this state, the Scotch fir is certainly one of the most picturesque trees we possess, and is the more valuable because each individual plant commonly takes a shape and character of its own. The avenues still remaining in Greenwich Park are composed chiefly of elm and Spanish chestnut, the latter being mostly confined to the upper part of the park. They are of different widths, and take various directions, many of them not appearing to have any definite object, and some being formed of two single rows, others of two double rows of trees. But there is one avenue—perhaps the finest—which, widening out at the base to correspond with the width of the hospital, is there composed of elms, but as it ascends the hill is made up wholly of Scotch firs, which are exceedingly good. In a general way, the trees in the avenues have been planted much too thickly, and have greatly injured or spoiled each other. In many instances, too, where plants have died out, they have been replaced by a most unhappy mixture of sorts, which, being also very poor specimens, detract much from the effect. At the upper part of the park are some aged and fine thorns, which have become very picturesque." The chestnuts in Blackheath Avenue have passed maturity, and every year seems to be telling on their strength. Many of them have magnificent trunks, and a few of them exceed eighteen feet in girth; some of the chestnuts, too, have attained a noble growth. The oaks are comparatively few, but among them are some of the largest trees in the park. The whole extent of the park is greatly varied in surface, and hence its great charm. As Mr. James Thorne, in his "Environs of London," remarks, "Everywhere the scenery is different, and everywhere beautiful; while from the high and broken ground by the Observatory and One-Tree Hill the distant views of London and the Thames, with its shipping, are matchless of beauty and interest. The park," he continues, "is the most popular of our open-air places of resort, and on a fine holiday is really a remarkable spectacle. It says something for the conduct of the crowds who resort hither, that the deer, of which there is a large number in the park, are so tame and fearless, that they will not only feed from visitors' hands, but even steal cakes from unwary children."
"One Tree Hill"—that particular spot rendered
famous by George Cruikshank, in his "Comic
Almanack," in the familiar lines—
"Then won't I have a precious lark
Down One Tree Hill in Greenwich Park!"
is so called from there having been but one tree on its summit; this tree, however, has long been greatly decayed, and six others were, some years ago, planted near it. It was in former times called "Five-tree Hill."
About the year 1816 it was proposed to raise a monumental trophy, in honour of the battle of Trafalgar, on the summit of Castle Hill, near the Observatory, but the project was relinquished for want of sufficient funds. This trophy was intended to have been elevated to a height of about 200 feet, and, had it been carried into effect, would have been a landmark to vessels on the river, and a conspicuous object to the country for miles around. On the brow of the hill, in the park, and about the front of the Observatory, you would see, till very recently, the old pensioners with their telescopes and glasses of every colour. Some of these heroes, who had served under Jervis and Nelson, had lost a leg or an arm, or possibly both; and yet they went about the park with their "baccy" as happy, to all appearance at least, as the credulous cockneys whom they delighted to cram with all sorts of improbable yarns about battles fought by "flood or field," in which they shot their cannonballs to the very longest of all possible ranges. This hill was a favourite place, not only for the Greenwich pensioners, but for gipsies and fortunetellers.
"The park," writes the ingenious Arthur Young, in a somewhat poetic strain, "is well stocked with deer, and affords as much variety in proportion to its size as any in the kingdom; but the views from the Observatory and One-Tree Hill are beautiful beyond imagination. … The projection of these hills is so bold that you do not look down upon a gradually falling slope, but at once upon the tops of branching trees, which grow in knots and clumps out of dead hollows and embrowning dells. The cattle which feed on the lawns, and appear in the breaks among them, seem to move in a region of fairy-land. A thousand natural openings among the branches of the trees break upon little picturesque views of the swelling turf, which, when lit up by the sun, have an effect pleasing beyond the power of fancy to exhibit. This is the foreground of the landscape; a little further the eye falls upon that noble structure, the hospital, in the midst of an amphitheatre of wood; then the two reaches in the river make that beautiful serpentine which forms the Isle of Dogs. … To the left appears a fine (?) tract of country, leading up to the capital itself, which there finishes the prospect."
The same view is thus described by Thomas Miller, in his work above quoted:—"Beautiful as is Greenwich Park within itself, with its long aisles of overhanging chestnuts, through whose branches the sunlight streams, and throws upon the velvet turf rich chequered rays of green and gold, yet it is the vast view which stretches out on every hand that gives its chief charm to the spot. What a glorious prospect opens out from the summit of 'One-Tree Hill!' London, mighty and magnificent, piercing the sky with its high-piled towers, spires, and columns; while St. Paul's, like a mighty giant, heaves up his rounded shoulders as if keeping guard over the outstretched city. Far away the broad bright river Thames rolls along till lost in the dim green of the fading distance, whilst its course is still pointed out by the spreading sail. Along this ancient road of the swans vessels approach from every corner of the habitable globe to empty their riches into the great reservoir of London, whence they are again sent through a thousand channels to the remotest homes in her islands and her colonies."
We have already mentioned that this park was a favourite lounge for Dr. Johnson during the time he was lodging in Greenwich. "We walked in the evening in Greenwich Park," writes Boswell. "He asked me, I suppose by way of trying my disposition, 'Is not this very fine?' Having no exquisite relish of the beauties of nature, and being more delighted with 'the busy hum of men,' I answered, 'Yes, sir; but not equal to Fleet Street.' Johnson: 'You are right, sir.'"
Greenwich Park, particularly at fair time, was the
scene of every variety of joyous hilarity, from "Kiss
in the ring," "Drop the handkerchief," and other
games, to the exciting rush and tumble down the
hill. The frolic and mirth everywhere visible here
on these occasions is well described in the following
"Ballad Singer's Apology for Greenwich Fair," in
"Merrie England in the Olden Time:"—
"Up hill and down hill, 'tis always the same;
Mankind ever grumbling, and fortune to blame!
To fortune, 'tis uphill, ambition, and strife;
And fortune obtain'd, then the downhill of life!
"We toil up the hill till we reach to the top;
But are not permitted one moment to stop!
Oh, how much more quick we descend than we climb!
There's no locking fast the swift wheels of Old Time!
"Gay Greenwich! thy happy young holiday train
Here roll down the hill and then mount it again.
The ups and downs life has bring sorrow and care;
But frolic and mirth attend those at the fair.
"My Lord May'r of London of high City lineage
His show makes us glad with, and why shouldn't Greenwich?
His gingerbread coach a crack figure it cuts!
And why shouldn't we crack our gingerbread nuts?
"Of fashion and fame, ye grandiloquent powers,
Pray take your full swing, only let us take our's!
If you have grown graver and wiser, messieurs,
The grinning be our's and the gravity your's!
"To keep one bright spark of good humour alive,
Old holiday pastimes and sports we revive.
Be merry, my masters, for now is your time—
Come, who'll buy my ballads? they're reason and rhyme."
Groups of nurserymaids and children are familiar features in the modern aspect of Greenwich Park. The latter flit, climb, and leap over every broken hillock, slide into every green dell, swing, toss, and tumble round and upon each sinewy tree, as if they were the legitimate possessors of the park, and lived entirely upon gingerbread, oranges, nuts, and lemonade—viands which, it seems proper to believe, are indispensable to the real enjoyment of these shady avenues.
In Albert Smith's description of Greenwich Fair, from which we have quoted largely in the preceding chapter, part of the scene is laid in the park. "It was a great relief to exchange the dust and jostling of the streets," he writes, "for the greensward and wide area of the park, albeit the grass was, in some places, perfectly shuffled away by the countless feet that passed over it in the course of the day. Observatory Hill was the chief point of attraction, and here the great mass of the people was collected. Nothing could be more animated or mirth-inspiring than the coup d'œil from the summit of this rise. The myriads of visitors all in their gayest dresses, for the humblest amongst them had mounted something new, be [were] it only a ribbon, in compliment to the holiday—the perpetual motion of the different groups and their various occupations—the continuation of the bustle to the river, seen beyond the hospital, covered with ships and steamboats as far as the eye could reach—and above all, the clear bright light shed over the entire panorama, except where the cloudy smoke of London hung on the horizon—altogether formed a moving picture of life and festivity only to be witnessed at Greenwich. The maimed and weather-beaten forms of the old pensioners offered odd contrasts to the lively active groups on every side. But even they were keeping holiday. Some of them, it is true, would have found it a task of no small difficulty to climb up the hill, or run down it, with the alacrity or headlong velocity of the younger visitors; so they contented themselves with sitting down upon the smooth turf to watch the others, or entertaining attentive listeners with their accounts of former engagements, in descriptions which depended more or less upon the fertility of their imaginations, but so ingeniously framed that they usually were contrived to end in an eleemosynary appeal to the generosity of the 'noble captain' or other complimentary officer who listened to them. The other chief entertainments on the Observatory Hill consisted in running down with helter-skelter rapidity, or scrambling oranges and apples amongst the boys on its declivity, which fruits were liberally showered forth by the more wealthy visitors on the summit. Frequently, an unwary damsel, crossing the slope, was entrapped by a handkerchief extended between two swift-footed swains, and compelled to finish her journey down the hill in much quicker time than she intended. And then what struggling there was—what exclamations of 'Ha' done, then!' and 'Be quiet, now!' until there was no breath left to give utterance to these remonstrances, and the victim was hurried to the foot of the steep between her two reckless persecutors, fortunate if she arrived at the foot without any downfall. For such accidents were of common occurrence, and roars of laughter arose from the crowds on either side when any luckless wight overran himself, and saluted the turf in consequence."
"If Easter Monday draws up the curtain of our popular merriments," writes the author of "Merrie England in the Olden Time," "Whit Monday, not a whit less merry, trumpets their continuation. We hail the return of these festive seasons when the busy inhabitants of Lud's town and its suburbs, in spite of hard times, tithes, and taxes, repair to the royal park of Queen Bess to divert their melancholy. We delight to contemplate the mirthful mourners in their endless variety of character and costume; to behold the festive holiday-makers hurrying to the jocund scenes, in order to share in those pleasures which the Genius of wakes, so kind and bounteous, prepares for her votaries. The gods themselves assembled on Olympus presented not a more glorious sight than the laughing divinities of 'One-Tree Hill.' What an animated scene! Hark to the loud laugh of some youngsters that have had their roll and tumble. Yonder is a wedding party from the neighbouring village of Chauton or Eltham. See the jolly tar with his true-blue jacket and trousers, checked shirt, radiant with a gilt brooch as big as a crownpiece, yellow straw hat, striped stockings, and pumps, and his pretty bride, with her rosy cheeks and white favours. How light are their heels and their hearts too! And the blithesome couples that follow in their train, novices in the Temple of Hymen, but who will, ere long, be called upon to act as principals! All is congratulation, good wishes, and good humour. Scandal is dumb; envy dies for the day; disappointment gathers hope; and one wedding—like a fool, or an Irish wake—shall make many."
About June the park may be seen in all its bloom and beauty—the fine old hawthorns are then still in full blossom, and the hundreds of gigantic elms and chestnuts are hung in their richest array of summer green, whilst here and there the deer cross and re-cross the shady avenues, or, crouching amid what is called the "wilderness," lie half buried in the fan-like fern. The hill and the plain below, and, in fact, the whole greensward round, are clothed in their holiday attire, the female part of the community lighting up the scene by the varied hues of their dress. At every few yards you meet with a new group of pleasure-seekers, whilst the long avenue which leads up to Blackheath is one continuous stream of merry-looking people.
On the south-west side of the park, and facing Blackheath, stands the Ranger's Lodge, a brickbuilt mansion, formerly the residence of Philip, Earl of Chesterfield, who purchased it about the middle of the last century, and considerably enlarged and improved it. In his "Letters" the earl calls it "Babiole" and afterwards "La Petite Chartreuse;" but it was commonly known as Chesterfield House, and his connection with it is still kept in remembrance by the name of "Chesterfield Walk," which has been given to the shady pathway running along under the park wall from the top of Croom's Hill. In 1807 the house became the residence of the Duchess of Brunswick, sister of George III., and was thereupon called Brunswick House. The duchess came hither in consequence of her daughter, Caroline, Princess of Wales, having had the adjoining mansion, Montagu House, assigned her as a residence when appointed Ranger of Greenwich Park, in the year 1806. On her death the house was purchased by the Crown, and appropriated as the residence of the Ranger. Here the Princess Sophia resided from 1816 till her death. In more recent times it was the residence of Prince Arthur, now Duke of Connaught, whilst studying for the Engineers.
Montagu House, which stood immediately to the south of the Ranger's Lodge, owed its name to having belonged to the Duke of Montagu, who bought it in 1714. Whilst it was the residence of the Princess of Wales, the grounds attached to it were enlarged by enclosing a portion of the park, called the "Little Wilderness." This now forms a part of the Ranger's Lodge. Montagu House was pulled down in 1815, but the name is preserved in Montagu Corner, at the end of Chesterfield Walk. At the junction of Chesterfield Walk and Croom's Hill is a large mansion, once the seat of General Wolfe, and the occasional residence of his son, the hero of Quebec, whose remains were brought hither before they were buried in Greenwich Church. The house was afterwards the residence of Lord Lyttelton.
On the south-west side of the park, above the summit of the hill, and in the rear of the house above mentioned, are several barrows, or tumuli, which, it has been conjectured, may have been the burial-places of the Danes during their encampment on Blackheath. Some of them were opened towards the end of the last century, when there were discovered in them spear-heads, human bones and hair, knives, fragments of woollen cloth, and other articles.
It is time now that we made our way once more
to the summit of the hill whereon stands the Observatory, a spot which Tickell calls—
"That fair hill where hoary sages boast
To name the stars and count the heavenly host."
The Observatory, as we have mentioned above, (fn. 2) occupies the site of the tower, commonly called "Greenwich Castle," which was built by Duke Humphrey. This tower was repaired, in 1526, by Henry VIII., and was used sometimes as a habitation for the younger branches of the royal family, sometimes as a prison, occasionally as a place of defence, and at other times as a residence for a favourite mistress. "The king" (Henry VIII.), writes Puttenham, in his "Art of English Poesy," "having Flamock with him in his barge, going from Westminster to Greenwich, to visit a fayre lady whom the king loved, who was lodged in the tower in the park; the king coming within sight of the tower, and being disposed to be merrie, said, 'Flamock, let us run.'" We do not know what was the result of the king's running, or what was its immediate object. In 1482, Mary of York, fifth daughter of Edward IV., died in this tower. In the reign of Queen Elizabeth it was called "Mirefleur," and the Earl of Leicester was confined in it, when he had incurred the Queen's displeasure by marrying the Countess of Essex. Henry Howard, Earl of Northampton, Lord Privy Seal, and the founder of Norfolk College, (fn. 3) in East Greenwich, had a grant of this tower from James I.; he is said to have enlarged and beautified the building, and to have made it his principal residence. In 1633, Elizabeth, Countess of Suffolk, died here. Ten years later, being then called "Greenwich Castle," it was considered of so much importance as a place of defence, that the Parliament took immediate measures to secure it against the King.
After the Restoration, M. de St. Pierre, a Frenchman, who came to London about the year 1675, having applied to King Charles II. to be rewarded for his discovery of a method of finding the longitude by the moon's distance from a star, a commission was appointed to investigate his pretensions. Lord Brouncker, President of the then young Royal Society, Sir Christopher Wren, the Surveyor-General, and City architect—for nearly half London was then in ruins—Sir Jonas Moore, Master of Ordnance, and many other "ingenious gentlemen" about the town and court, composed the board, "with power to add to their number," which power they exercised by the addition of a certain Mr. John Flamsteed, who was introduced by Sir Jonas Moore, and whose name, from that day to this, has been associated with this hill.
Flamsteed, who was born at Denby, Derbyshire, in 1646, had already distinguished himself as an astronomer; for, previous to the erection of this Observatory, he had made sundry observations of the heavenly bodies in a turret of the building called the "White Tower," in the Tower of London, which turret is still called the "Observatory." On hearing the Frenchman's proposals, Flamsteed at once pointed out their impracticability, in consequence of the imperfect state of the tables representing the motions of the moon, and the inaccuracies of the existing catalogues of the fixed stars. He likewise set to work on some observations of his own, which at once frustrated the schemes of St. Pierre, who was no more heard of. The commissioners thereupon communicated the results of Flamsteed's observations to the king; "his Majesty is startled by the assertion that the stars' places are erroneously known, and exclaims, with his childish vehemence, that 'he must have them anew observed, examined, and corrected for the use of his seamen.' The king is then told how necessary it is to have a good stock of observations of the moon and planets, and he exclaims that 'he must have it done;' and when he is asked who could or who should do it, he replies, 'The person who informs you of them.'" Sir Jonas Moore accordingly conveys to the young astronomer the royal warrant appointing him "Our Astronomical Observator," and enjoining him "forthwith 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, so as to find out the so-much-desired longitude of places, for the perfecting the art of navigation." For this important service he was to receive the munificent stipend of £100 per annum!
The next thing to be settled was the site of the Observatory, and, upon the advice of Sir Christopher Wren, Greenwich Hill was chosen. The old tower was accordingly ordered to be demolished; and the first stone of the new building was laid in August, 1675. In exactly a year from that date the edifice was handed over to Flamsteed, and from him it acquired the name of Flamsteed House. In the following month he began his observations, with a sextant of six feet radius, contrived by himself, and such other instruments as were then known. Notwithstanding his scanty income, and the difficulty he experienced in obtaining such instruments as he required, Flamsteed's zeal overcame all obstacles, and during his lifetime the Observatory rose to that first rank which it has ever since maintained among similar institutions.
It may be worth while to consider here what was the state of practical astronomy at the time when Flamsteed commenced his labours. Neither telescopes nor clocks had yet been introduced into observatories; the star catalogue of Tycho Brahe was derived from observations made with instruments furnished with plain sights; and this, together with the Rudolphine tables of the sun, moon, and planets then known (which were constructed from elements quite as rough), were the only materials existing for the use of the theoretical astronomer. Flamsteed, who knew what was needed, and who had a much better idea than any man of his time of the means necessary for producing comparatively good observations, set about his task with vigour. He was totally unprovided with instruments at the public expense, but he brought with him to the Observatory an iron sextant of six feet radius, and two clocks, given him by Sir Jonas Moore, together with a quadrant of three feet radius, and two telescopes, which he had brought with him from Denby. With these instruments he worked till the year 1678, when he borrowed from the Royal Society a quadrant of fifty inches, which, however, he was allowed to retain only a short time. It must be borne in mind that the advantages of the system of meridian observations were unknown, or nearly so, at this time. The sextant was employed to measure the distances of an object to be observed from some standard stars, or stars whose places were supposed to be better known, and a laborious calculation was necessary to deduce the resulting place of the body in every instance. This gave, however, no means of fixing the place of the body with respect to the equinox; and Flamsteed, finding the absolute necessity for an instrument fixed in the plane of the meridian, applied to the Government. He was not denied; but being wearied with repeated promises which were never kept, he at length resolved to make a "mural arc" at his own expense, and this instrument was finally erected, and divided with his own hands in 1683. It was, however, a failure; and his observations were continued for several years longer with the sextant. The minor obstructions and vexations to which Flamsteed was subjected we have not space to mention. It is sufficient to say that, during the whole time that he officiated as Astronomer-Royal (nearly half a century from his first appointment), he was not supplied by the Government with a single instrument. The only assistance he was furnished with was that of "a silly, surly labourer" to assist him with the sextant; the other assistants and computers he provided at his own expense.
In 1684 Flamsteed was presented to the living of Burstow, in Surrey; having been from his early life desirous of devoting himself to the duties of the ministry. "My desires," he says, in his "Autobiography," "have always been to learning and divinity; and though I have been accidentally put from it by God's providence, yet I had always thought myself more qualified for it than for any other employment, because my bodily weakness will not permit me action, and my mind has always been fitted for the contemplation of God and his works." His father died a few years afterwards; and these two circumstances improving his estate, he determined to construct a new "mural arc," stronger than the former; and this instrument, famous as really commencing a new era in observing, was constructed by Mr. Abraham Sharp, his friend and assistant, at an expense of £120, no portion of which was reimbursed to him by the Government. All Flamsteed's former observations were of little value; no fundamental point of astronomy was settled by them; and they merely served for forming a preliminary or observing catalogue of objects to be well observed with his new instrument. From the date of the use of this instrument, 1689, the useful labours of Flamsteed commenced; every observation made after this was permanently useful, and could be applied to determine some important point. With this instrument, after verifying its position and determining its adjustment, he set about the determination of those cardinal points in astronomy, the position of the equinox, the obliquity of the ecliptic, and other fundamentals, without which the correct positions of the fixed stars and the planetary bodies could never be ascertained. His methods and processes are explained by himself in the "Historia Cœlestis," a work in three folio volumes, the third of which contains his catalogue of 2,935 stars, carried down to the year 1689. His work still holds a high place in the history of astronomy.
What instruments Flamsteed had to work with, then, we are assured he had to provide and pay for himself; and in order to do this, he was compelled to turn "teacher." Government had already imposed upon him the education, monthly, of two boys from Christ's Hospital, as if his tedious watches by night, and his laborious calculations by day, were not sufficient return for his paltry pittance, which was reduced by a tax to £90 a year. He thereupon, as we have said, gave lessons in his favourite science, and obtained for pupils sundry dukes and lords, with many captains of vessels and East India servants, thus augmenting his pecuniary means.
Flamsteed appears soon to have made many friends, among whom was the venerable John Evelyn, who, under date of September 10th, 1676, makes this entry in his "Diary:"—"Din'd with me Mr. Flamsted, the learned astrologer (sic) and mathematician, whom his Majesty had established in the new Observatory in Greenwich Park, with the choicest instruments. An honest, sincere man." Evelyn, we need scarcely state, should have written "astronomer," instead of "astrologer." But he is not the only person who has made this confusion. For it is a fact worthy of being placed on record that seldom a week passes without ladies driving from London in their carriages to the doors of the Observatory, and inquiring if they can have their "horoscopes" cast, evidently showing that they do not know the difference between astrology and astronomy. It is to be feared that on this subject great superstition prevails, even among the "educated" classes; and that whilst fortune-tellers, who practise on poor servant-girls, are pounced upon by the police, some of the professors of the secret science, called "spiritualism," are making fortunes, by charging a guinea for every consultation, or séance! But we must now return to our subject. On the 14th of June, 1680, John Evelyn writes:—"Came to dine Dr. Burnet, author of the 'History of the Reformation.' After dinner we all went to see the Observatory and Mr. Flamsteed, who show'd us divers rare instruments, especially the greate quadrant. My old friend Henshaw was with me." Again, some three years later, namely, on the 1st of August, 1683, we meet with this entry:—"Came to see me Mr. Flamsted, the astronomer, from his Observatorie at Greenwich, to draw the meridian for my pendule," &c.
About this time, or shortly after, Flamsteed became friendly with Sir Isaac Newton, who was engaged in investigating the irregularities of the moon's motions, for the confirmation of his theory of universal gravitation, and who required accurate observations of the moon for comparison of fact with fancy. No one but Flamsteed could supply these, and from time to time Newton visited him in order to obtain them. But this friendship was not of long duration. A difference arose between them, on account of an innocent statement by Flamsteed, to the effect that he had furnished Newton with a mass of lunar observations to assist him in his investigations, getting into print. Some angry correspondence ensued, and the dispute, after slumbering for a few years, broke out into a lamentable quarrel. In course of time, Flamsteed's valuable store of observations, extending over the period of thirty years which he had then passed as Astronomer-Royal, were prepared for publication. Prince George of Denmark, consort of Queen Anne, undertook to bear the expense of printing; and a committee, with Sir C. Wren and Newton among the number, was appointed to examine the manuscript, and see the work through the press. During its progress, the latent quarrel between Flamsteed and Newton broke out afresh, and arrived at its culmination, turning upon the difference that existed between Flamsteed and the referees concerning the plan of publication of his work. The book, "mangled and garbled," was at length published, and so much did it annoy its author, that when, a few years after, the undistributed copies, about three-fourths of the entire impression, were placed in his hands, he at once committed the whole of them to the flames, "as a sacrifice to heavenly truth," and "that none may exist to show the ingratitude of two of his countrymen, who had used him worse than ever the noble Tycho was used in Denmark." He then resolved to publish a complete edition of his observations on his own plan, and at his own expense. It was to appear in three volumes; but on the completion of the second volume, his life's weary toil was brought to a close, on the last day of the year 1719.
Flamsteed was succeeded by Dr. Halley, an astronomer also of great eminence, who, finding upon his appointment that the Observatory was destitute both of furniture and instruments (Flamsteed's having been removed by his executors as his personal property), furnished it anew, and fixed a transit instrument. Its introduction is stated to have been the most important step that had been made. It is the most simple and effective of all astronomical instruments; and up to the present time, the only changes that have been made in the means for observing the right ascensions of the heavenly bodies, are those which secure to it the utmost possible stability and accuracy of workmanship and adjustment. With it alone Halley continued to make observations of the moon till the year 1725, when an eight-foot mural quadrant, made by Graham, was set up at the public expense. Of the small salary received by Dr. Halley for his important duties the following anecdote has been related:—On the accession of George II., the queen consort, Caroline, made a visit to the Royal Observatory. Being pleased with everything she saw, and understanding the smallness of the astronomer's salary (£100 per annum), her Majesty very graciously said she would speak to the king to have it augmented, to which Dr. Halley replied in alarm, "Pray, your Majesty, do no such thing; for should the salary be increased, it might become an object of emolument to place there some unqualified needy dependant, to the ruin of the institution." However, understanding that the doctor had formerly served the Crown as a captain in the navy, the queen soon after was able to obtain a grant of his half-pay for that commission, which he accordingly enjoyed from that time up to the end of his life.
Halley died in 1742, and his successor was Dr. Bradley. This eminent astronomer made a noble series of observations, extending over the twenty years during which he held the post. In 1750 many valuable additions were made to the stock of instruments. Bradley died in the year 1762, and was succeeded by Dr. Bliss, who lived only till March, 1764. The office next devolved upon Dr. Maskelyne, who for nearly fifty years performed the duties with wonderful assiduity; scarcely ever leaving the Observatory, except on some important scientific business, and making all the laborious and delicate observations himself, although he had the co-operation of a skilful assistant. He first suggested the publication of the Nautical Almanack, a work of indispensable use to seamen, of which he edited no less than forty-nine volumes. At his death he left four large folio volumes of printed observations as the result of the patient labour of his life. In 1767 an order was issued by George III. that the observations made at Greenwich should be published, under the superintendence of the Royal Society; they have, accordingly, since been published annually by that learned body. The principal addition made to the Observatory during Maskelyne's directorship was the building of the "circle" room, contiguous to and east of the transit-room. Maskelyne died in 1811, leaving behind him an enviable reputation. The observations made by this astronomer during his forty-seven years' residence at Greenwich were so valuable, that it has been remarked of him by his biographer, that if the whole materials of science should be lost except the volume of observations left by him, they would suffice to reconstruct the edifice of modern astronomy. He was succeeded by Mr. John Pond, who held office till the year 1835, when ill health compelled him to resign; he died in the following year, and was buried at Lee, in the same tomb with his predecessor, Dr. Halley. During Mr. Pond's directorship the Observatory acquired that organisation which it has since retained, and which was necessary to enable it to meet the demand made upon it by the requirements of modern science. On his entrance upon his duties he began, like his predecessors, with one assistant; but on his representations and urgent entreaties for increase of the establishment, he finally obtained six assistants; and this amount of force for the astronomical department of the Observatory has been continued with some modifications to the present time. Pond was peculiarly skilful in the theory of astronomical instruments, and in the interpretation of the results afforded by them. Sir George Airy, in one of his official reports, states that he regards him as the "principal improver of modern practical astronomy."
On the resignation of Mr. Pond, Mr. George Biddell Airy, then Director of the Observatory at Cambridge, was appointed to the vacant office. "Under his presidency," writes Mr. Carpenter, in the Gentleman's Magazine (February, 1866), "the Observatory has been gradually augmented and brought to its present complete and perfect condition. Old instruments, very perfect in their way, but still behind modern requirements, have been laid aside, and new systems introduced. Every improvement that modern science could supply, and every appliance that modern mechanical skill could suggest, have been made subservient to the utilitarian principles of the Observatory under its present organisation."
Greenwich Observatory has little to recommend it as a building. It was never intended for show, but for work. It was constructed in haste, chiefly with the materials of the old tower, and some spare bricks that lay available at Tilbury Fort. The admissions to the building are strictly limited to such individuals as are most likely to be benefited by visiting it, and idling sightseers are carefully excluded. A card is kept in the porter's lodge, which explains that the privilege of visiting the Observatory is of necessity very limited, those officially privileged being officers of the Royal Navy and gentlemen officially connected with the Admiralty; other visitors are required to be furnished with an introduction from some person of scientific distinction.
A few objects arrest attention outside the walls of the edifice. For instance, the twenty-four hour electric clock, supposed by the uninitiated to be kept going by the sun; the public barometer, with its indices, showing the highest and lowest readings during the past few hours; the little windmill like a child's toy on the roof; and the high pole with a light at the top, conjectured to be a beacon to show the longitude at sea. One other external object must not be overlooked: this is an iron plate fixed against the wall, with a number of brass plugs and pins projecting from it, with the inscriptions, "British Yard," "Two Feet," &c., over them. "It will probably be asked," says Mr. Carpenter, in an article in the Gentleman's Magazine, from which we have already quoted, "what has a yard-measure to do with astronomy? It has a great deal. One important branch of practical astronomy is the measurement of time, and time is the only natural standard this earth possesses; it is the only thing that is invariable. Now the British imperial standard yard, by law established, is a measure of length, bearing a certain definite proportion to the length of a pendulum which, at a given temperature and under other specified conditions, beats accurately seconds of mean solar time. This is the connection between astronomy and yard-measures. Any one who desires to secure an accurate yard-measure may do so by carrying to Greenwich a rod about a yard long, and truly adjusting it by means of the appliance there exposed for the public benefit. He will find two plugs, the distance between which is exactly a yard when the temperature of the air is about 60°, and two pins for the support of the rod to be adjusted. The plugs are bevelled off a little on their insides, and the points that are exactly a yard apart are marked upon their upper surfaces by arrow-heads. If the rod will not go in as far as the arrow-heads, it is too long; if it passes them loosely, it is too short. Similar plugs are provided for shorter measures, down to three inches."
On passing inside the gate, the first object that
presents itself is a range of low buildings immediately to the left, railed off from the more common
portions of the court. The old-fashioned yet rather
picturesque gables and roughly-tiled roofs of these
buildings, and their general humble aspect, give
no evidence of their use, except what may be
gathered from the slits, closed by shutters, which
in two places intersect them, and the domes that
flank them at their eastern and south-western
extremities; yet in these unpretending rooms not
only are all the observations made which give its
fame to the establishment, but the reduction of
them is also performed there, and they are rendered fit for the immediate use of the astronomer.
The door immediately opposite, as we cross the
court, is that of the Astronomer-Royal's residence,
all the apartments of which are on the groundfloor, and situated on either side of a long gallery
running nearly east and west. On the wall of the
building, near this doorway, is a slab containing
the original inscription set up at the erection of the
Observatory; it is as follows:—
Carolus II., Rex Optimus,
Astronomiæ et Nauticæ Artis
Speculum hanc in utriusque commodum Fecit,
Anno Dni. MDCLXXVI., Regni Sui xxviii.,
Curante Jona Moore, milite.
A doorway near the eastern end of the range of buildings leads into the transit-circle room, one of the principal observing-rooms of the establishment. To the reader not familiar with the instruments and processes of astronomy it may be desirable to explain that the transit-instrument is a telescope which is supposed theoretically to describe the plane of the meridian. For this special purpose it is furnished with two axes, terminating in two wellpolished equal cylindrical pivots; and these pivots being placed in bearings sunk in the stone piers shaped like the letter Y (technically called "Y's"), the instrument is capable of revolving freely.
We may here remark that the principal duty of the practical astronomer is the determination of right ascensions and polar distances. "Right ascension," says Mr. Carpenter, "is the distance of a heavenly body from an imaginary point—or, more properly, a great circle passing through a point—in the heavens, called the first point of Aries. It is a well-known fact that the earth completes one revolution upon its axis in the course of twenty-four hours; and this rotation affords a ready means of measuring right ascension. We have only to ascertain how much the earth turns between the time that the first point of Aries crosses the meridian, and the time that the star to be measured crosses it. To measure this two things are requisite—a clock, and something like a line to see the stars pass over… A telescope is firmly fixed to a horizontal axis, and mounted upon two stone pillars, just as a gun is mounted upon its trunnions, free to move vertically, but incapable of moving horizontally. The telescope is so adjusted, that upon spinning it round, it sweeps out an imaginary plane which lies exactly due north or south of the Observatory. In its focus is placed an extremely fine vertical line—in reality, a fragment of spider's web. Now, to whatever point of the heavens we direct this telescope, bearing in mind that it can only move in a vertical direction, that spider-line represents the astronomical meridian at that point. The virtual meridian of Greenwich is therefore really no more than half an inch of cobweb. If, then, we take a clock, and set it at oh. om. os. when the first point of Aries crosses the meridian, it will be obvious that the time by that clock, when any object passes the spider-line in the telescope, will be its distance from that point expressed in time; for instance, if we direct the telescope to a star that we see approaching the meridian, and observe that it crosses the cobweb at 5h. 21m. 45s., we know, assuming the clock to be correct, and the instrument in proper adjustment, that the right ascension of the star is 5h. 21m. 45s. From the circumstance of all objects crossing or transiting the field of this telescope, it bears the very appropriate title of the 'Transit Instrument.' It was invented by Romer, a Danish astronomer, about the year 1690, and was first used at the Greenwich Observatory by Halley some thirty years after."
Upon the same wall on which hangs Halley's primitive instrument, are suspended two or three other transit instruments, which in their time have doubtless rendered good service to astronomical science. These are the instruments introduced by Dr. Bradley, and also Troughton's noble instrument, used by Maskelyne and Pond, and by the present Astronomer-Royal up to the year 1850, when it was dismounted to give place to the gigantic "transit-circle" now in use. This lastmentioned instrument is, in fact, a combination of two instruments, seeing that it has also superseded the "mural quadrant," by means of which a star or planet's polar distance was formerly ascertained. This instrument is twelve feet in length, and its largest glass is eight inches in diameter. Attached to the telescope is the circle which answers to the "mural circle;" around its circumference is a narrow band of silver, upon which are engraved those divisions representing degrees of angular measurement, of which the whole circle contains 360. These degrees are further subdivided into smaller intervals of five minutes, and the intermediate minutes and seconds, and decimals of a second, are what is technically termed "read off" by means of micrometers, six of which are used, and their mean taken, to eliminate errors of observation, &c. These micrometers are affixed to one of the piers supporting the instrument, the pier itself being perforated to allow the divisions to be seen through it. Another circle attached to the telescope is a clamping circle, for the purpose of fixing the instrument rigidly during an observation. Counterpoises in various parts, apparatus for raising the instrument, and other appliances necessary for purposes of adjustment, make up the other details of the "transit circle," in front of which stands the "transit clock," which is its indispensable accessory.
We have arrived, let us suppose, a little before noon; the sun is about to cross the meridian, and an observation is to be made. Shutters in the roof are thrown open, the great telescope is swung up and fixed in position, and an observer seats himself at the lower end of it. Peeping through the instrument, all that could be seen by an "outside" observer would be a number of vertical lines, technically called "wires," but in reality so many pieces of cobweb, as mentioned above, stretched across the field of observation at irregular distances. The centre one is the celebrated meridian of Greenwich, or, at all events, it represents it, and it is curious to reflect that from this centre line ships of all civilised nations, and in all parts of the known world, are reckoning their distances. What the regular observer has to do is to record the precise instant at which the sun's edge, or "limb," as astronomers call it, passes that central "wire." In any single observation, however, he may be a little at fault, and for the sake of greater accuracy, therefore, he notes the instant at which it passes over all the "wires," and then strikes an average between them. Slowly the sun creeps up to the first line, and the observer lightly taps a little spring attached to the telescope. The second "wire" is reached, and again the spring is tapped, and so on throughout the whole seven or nine webs employed in the observation. This spring is connected with a telegraphic wire extending to a "chronograph" in a distant part of the building, which consists of a cylinder, around which a sheet of white paper has been strained. The cylinder itself is revolved by the pendulum of an electric clock, which, instead of oscillating backwards and forwards, swings round in a circle, thus producing a motion perfectly uniform and unbroken. A little steel point, which is travelling over the surface of the paper, is in electric communication with the spring attached to the great telescope; "and," observes a writer in Cassell's Family Magazine, "every time the observer taps the spring, this little travelling point pricks into the paper, thus recording that the sun has just crossed a 'wire.' This in itself, however, would not be a record of the time of transit if it were not that another little steel point, which is in connection with a galvanic clock in another part of the building, has previously marked the sheet of paper into spaces representing precise seconds of time. On the completion of the observation the paper may be removed from the cylinder, and affords a permanent record of it."
One other object in the apartment containing the "transit-circle" should not be passed unnoticed; it is the identical instrument with which Bradley made his important discovery of the aberration of light.
The next important instrument is the altitude and azimuth, or, as it is termed, for shortness, the "altazimuth," which is located in the south dome of the Observatory buildings. This instrument was erected in 1847, for the sole purpose of observing the moon. Next to the sun, the most important of the heavenly bodies is the moon, for, independently of her use in regulating the division of the year into months, and creating the tides of the ocean, she is indispensable to nautical science, as her motions afford the only means of accurately determining the longitude at sea. The Observatory was originally founded for observations necessary to bring to perfection the lunar tables, and for the improvement of nautical astronomy. The observation of the moon in every part of her orbit has always been, therefore, an object of first-rate importance. To effect this, meridian observations have been regularly made in fixed observatories, as alone giving results of the requisite excellence. But, since the moon is invisible at her meridian passage for nearly one-third of her orbit—viz., for about four days, on the average, before conjunction, and for four days after it—and since also a great many observations in each lunation are necessarily lost by cloudy weather, it became a great desideratum to supply, if possible, by extrameridional observations, these defects. The altitude and azimuthal instrument was evidently the kind of instrument that must be employed for this purpose, because, its axes being one horizontal and the other vertical, the parts of the instrument are equally affected by gravity in every position, and the only thing wanted to produce observations which should rival those made with the transitinstrument and mural-circle, would be sufficient firmness. To secure this the Astronomer-Royal adopted as his principles of construction, "to form as many parts as possible in one cast of metal, to use no small screws in the union of parts, and to have no power of adjustment in any." The instrument is, therefore, as the visitor would at once see, of unusual weight and solidity. One of the two vertical cheeks that are on each side of the telescope carries, in one cast of metal, the four microscopes for reading the vertical circle, and the supports of the levels parallel to the plane of that circle. The lower piece connecting these cheeks, or the base plate, carries in one cast the four microscopes for reading the horizontal or azimuthal circle, and supports two levels parallel to the horizontal axis; and the upper connecting piece carries two other levels similarly situated on the upper pivot. These pieces are most firmly connected with the side vertical cheeks by means of planed surfaces and screw bolts. The vertical circle was made in two casts of metal—viz., the cylindrical part, the spokes and pivots on one side, the object-end and the eye-end of the telescope were made in one cast; and in the other cast are included the spokes and pivot on the other side. Thus the whole of the essential parts of the instrument, with regard to firmness, were made in six casts of metal. The weight of these six parts is about sixteen hundredweight.
Some idea of the importance of the Greenwich lunar observations may be inferred from the circumstance that, during the century ending with the year 1851, Greenwich contributed nearly 12,000 observations of the moon towards the improvement and perfection of the vexatious lunar theory; all reduced under the direction of Sir G. B. Airy, and rendered immediately available for the investigations of the physical astronomer, the lunar tables now in use being chiefly based upon these observations. Since the introduction of the "altazimuth," the number of observations of the moon formerly made here in the course of each year has been about doubled, and, as a natural consequence, the value of the Greenwich lunar observations has been largely increased.
It may be asked by some of our readers, how are the Greenwich observations of the moon connected with navigation? A few lines by the author quoted above may be given as a reply. "The observing astronomer," he writes, "observes accurately the position of the moon in the heavens at all times and under all circumstances. He turns his observations over to the physical astronomer. The physical astronomer deduces from them the laws that govern the moon's motions, and represents those motions by numerical tables. These tables are put into the hands of the computer of the Nautical Almanac, who, by their aid, predicts the place the moon will occupy, with reference to proximate stars and otherwise, at every hour of the day and night throughout the year, and publishes these 'lunar distances' in that work, three or four years in advance, for the benefit of seamen starting on long voyages. The mariner observes the moon and stars near her with his sextant, and from comparison of his observations with the positions given in the Nautical Almanac computes his longitude, and ascertains the place of his vessel on the trackless ocean."
We will now pass on to the interior of the very large dome, or rather drum, that caps the southeastern extremity of the Observatory. In it is a magnificent specimen of the class of instrument known as the "equatorial." The dome itself, which has an opening closed by curved shutters, sliding upwards and downwards, moves round with sufficient ease by means of a toothed wheel and rack, the manual power being applied at the ends of long radial bars. "The great equatorial telescope was mounted about the year 1860, under the direction and from the plans of the present Astronomer-Royal." The author whom we have already quoted remarks that, "It is the largest instrument in the Observatory, and of its kind is one of the finest in the world. Its object-glass, which is thirteen inches in diameter, and has a focal distance of eighteen feet, alone cost £1,200. The most curious feature in this telescope is the clockwork arrangement by which it follows any object under examination. It is used chiefly for what may be called gazing purposes—such, for instance, as the scrutiny of the marvellous eruptions on the surface of the sun, or the mountains of the moon, and it is often necessary to continue such observations for hours together. It is plain, however, that if an observer is examining the face of the sun, the motion of the earth will gradually bear him and his telescope eastward until the great luminary is lost to view. He will steadily creep out at the western side of the field. This is obviated by the operation of a clock driven by falling water. This powerful piece of mechanism is connected with the great iron framework supporting the telescope, and just as the earth creeps round from west to east, the telescope and all that pertains to it is borne round from east to west. Thus, so far as the motion of the earth is concerned, the sun, moon, or stars, as seen through the great equatorial, will appear to be perfectly stationary."
We have now seen all the more prominent features of the astronomical department of Greenwich Observatory, though there yet remain many other objects of the utmost scientific interest—such as rain-gauges, hygrometers, anemometers, and thermometers, placed in all kinds of positions, and under all kinds of conditions. In one room is a very large number of Government chronometers, required for the use of ships; while in a building apart from the Astronomical Observatory, is a Magnetic Observatory, established about the year 1840, for the purpose of ascertaining and recording the various phenomena of the magnetic currents of the earth. "The principal instruments in the Magnetic Observatory," writes Mr. J. Carpenter, "are three magnets about two feet long, one suspended by a skein of silk fibres, in the plane of the magnetic meridian, for indicating the variation in declination of the needle; another, suspended by two silk skeins, at right angles to the meridian, for indicating the earth's horizontal magnetic force; and a third, poised upon knife edges, like a scale-beam, for showing the vertical magnetic force. In order to secure as uniform a temperature as possible, these instruments are mounted in a subterranean apartment. Until the year 1847 it was customary to observe the positions of these magnets every two hours throughout the day and night, but it afterwards became evident that some mode of perpetual registration of their movements was absolutely necessary, and a reward of £500 was offered for some system by which this could be effected. The reward was gained by Mr. Brooke, a medical gentleman of London, who so completely solved the problem by the skilful application of photography that his method has ever since been used with perfect success in this and other magnetic observatories, entirely superseding the old system of eye-observation. The simple process is as follows:—Each magnet has a concave mirror affixed to it in such a manner that every deflection of the magnet deflects the mirror also. A gas-burner is so placed that a beam of light from it is always shining upon the mirror. At some distance from the magnet is a cylinder, around which is wrapped a sheet of photographic paper. The beam of gaslight falling on the mirror is reflected, as a little spot of light, on to the paper, and as the magnet moves the spot of light changes its position on the sheet, leaving its trail wherever it goes. The cylinder is made to revolve once in twenty-four hours, and the magnet thus records, night and day, its minute changes of position. Two magnets trace their movements upon the same sheet of paper, which is changed every morning, and the latent image brought out, or 'developed,' in the usual way. Across the centre of the sheet runs a fine straight line, called the base line, its place relative to the traces of the magnets serving as a zero from which the various positions of the magnet during the day are measured, the time being ascertained by a time-scale laid down on each sheet. In a similar manner the movements of delicate galvano-meters, placed in the circuits of long lines of telegraph wires with 'earth-plates' (masses of metal buried in the earth) at their extremities, register the fluctuations of those mysterious galvanic currents that are constantly circulating through the earth, and to which the name of 'earth-currents' has been given. The height of the barometer and the changes of temperature during the day and night are simply recorded by photography. In the case of the barometer, this is effected by means of a float on the surface of the mercury in a syphon tube, which, as it rises and falls, raises or lowers a diaphragm with a small hole pierced through it, allowing the light from an adjacent gas-flame to fall upon the sensitive paper, which is, in this case, wrapped around a vertical revolving cylinder. In the case of thermometers, the gas-light is allowed to shine through the glass tube upon the passing paper, and the mercury, rising and falling, serves as a shutter that cuts off the light at various heights corresponding to the various temperatures.
"Here we see the use of the high pole with a light at the summit, that so mystifies the outer world. It is for the purpose of supporting a wire that is suspended from its top to the summit of the Astronomical Observatory. This wire collects electricity from the atmosphere, and conducts it down another wire to the room beneath, where, by means of appropriate electrometers, its quantity is measured and its quality ascertained. The light at the mast-head is for the purpose of preserving the apparatus in a degree of warmth and dryness essential to produce insulation, and prevent the escape of the atmospheric electricity. … In connection with this department we must visit the anemometers, or wind-gauges. For this purpose it is necessary to mount to the highest point of the Observatory. One of these anemometers is, to all outward appearance, nothing more than a simple vane; but if we enter the turret upon which it is mounted we shall see that its motions are communicated, through a little simple machinery, to a pencil which is tracing upon a sheet of paper, moved by clockwork, every motion of the vane above; and thus recording to all futurity every change of wind throughout the day and night. Another pencil is marking the force of the wind, or its pressure in pounds upon the square foot; while a third, only called into use in rainy weather, shows the quantity of rain that falls and the rate of its falling. On another part of the roof is the little windmill to which we have before alluded. This is also an anemometer; its use is to determine the velocity of the wind, or, in other words, the length in miles of the current of air that passes over Greenwich in a given time. It consists of four cups, mounted upon horizontal arms attached to a vertical spindle; the rotation of the cups, which are spun round by the wind, is communicated through the spindle to a train of wheels and dials, which latter indicate the exact number of hundreds or thousands of revolutions performed by the cups, and from this the velocity of the wind is deduced.
"Here, too, we are brought into closer contact with the time-signal ball; a wood and leather sphere, five feet in diameter, that is raised every day at five minutes before one o'clock, and dropped at one precisely by the galvanic motor clock, the clock giving a signal that, by means of magnetism, pulls a trigger, and disengages the ball."
Nothing, perhaps, throughout the Observatory is calculated to strike the visitor with greater astonishment than the motor clock above referred to. There is nothing very remarkable in its appearance, but the work it accomplishes renders it, perhaps, the most wonderful clock in the world, and certainly the most important one in England. The writer above quoted continues—"It regulates several clocks within the Observatory, as well as the large one already referred to outside the gates; one at Greenwich Hospital Schools, another at the London Bridge Station of the South-Eastern Railway, another at the Post Office, St. Martin's-leGrand, and another in Lombard Street. Once every day it telegraphs correct time to the great clock tower at Westminster; it drops the signalball over the Observatory, another near Charing Cross, and one at Deal; it fires time-guns at Shields and Newcastle, and every hour throughout the day it flashes out correct time to each of the railway companies. All this is accomplished, as it were, by the mere volition of the clock, and without any human interference whatever. Every morning it is corrected by an actual observation of a star; and thus, without being aware of it, do we every day start our trains, and make our appointments, and take our meals by the motions of the heavenly bodies as observed and recorded during the preceding night."
It is no longer, therefore, "the Horse Guards' clock," but Greenwich Observatory, which regulates the time of all the clocks and watches in London. The Post Office authorities have granted the special use of a system of electric wires to the inventors of a method for synchronising clocks. The arrangements recently completed bring the Greenwich Observatory into direct communication with the establishment at Cornhill of Messrs. Barraud and Lund, the inventors of an apparatus by means of which existing clocks can be automatically "set to time." The mechanism is of the simplest kind; it interferes in no way with the works of a clock, and can be applied to any timepiece in or out of doors. Any number of clocks, varying in size and calibre, can, upon receipt of one time-signal, be simultaneously set to accord with each other in accurately denoting Greenwich time. A very small outlay, it is said, will secure true Greenwich time to every City establishment.
An account of what has been done at the Greenwich Observatory, as well as of what is in progress, is given in the annual report of the AstronomerRoyal, and the results are issued from time to time in a more substantial form in the shape of such works as the Astronomer-Royal's "Corrections of the Elements of the Lunar Theory" (1859); the "Greenwich Catalogue of 2,022 Stars" (1864); and "Catalogue of 2,760 Stars" (1870). More recently the subjects of solar photography and spectroscopy have been added to the routine investigations of the Observatory. From the annual report published in 1875 we learn that the system of time-signals, originating in the Observatory and disseminated by the Post Office telegraph through the whole of England, and to Scotland and Ireland, continued to spread, and that it now appeared to be a national institution. The Lombard Street clock has been maintained in all the accuracy that is required for post-office purposes, with scarcely a failure; and the Westminster clock has been so efficiently regulated, under the check of automatic report to the Observatory, that on 83 per cent. of the days of the year its error is below one second. In concluding his report, Sir George Airy remarks that the Observatory was expressly built for the aid of astronomy and navigation, for promoting methods of determining longitude at sea, and, as the circumstances that led to its formation show, more especially for determination of the moon's motions. All these imply as their first step the formation of accurate catalogues of stars, and the determination of the fundamental elements of the solar system. These objects have been steadily pursued from the foundation of the observatory—in one way by Flamsteed, in another way by Halley, and by Bradley in the early part of his career; in a third form by Bradley in his later years, by Maskelyne (who contributed most powerfully to lunar and chronometric nautical astronomy), and for a time by Pond; then, with improved instruments, by Pond, and by himself (Sir G. B. Airy) for some years, and subsequently with the instruments now in use. It has been his own intention to maintain the principles of the long-established system in perfect integrity, varying the instruments, the modes of employing them, and the modes of utilising the observations by calculation and publication, as the progress of science might require.
Viewing the instruments, however, now in use, and the increase of expenses, which were lower than the work done, the Astronomer-Royal expresses a hope that the National Observatory will always remain on the site where it was first planted, and which early acquired the name of "Flamsteed Hill."
The Observatory is annually inspected by a body of scientific persons of high standing, who are commissioned by the Government of the day to see that the institution is maintained in a state of efficiency.