Читать книгу The Royal Observatory, Greenwich - E. Walter Maunder - Страница 9

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For the first century of its existence, the lives of its Astronomers Royal formed practically the history of the Royal Observatory. During this period, the Observatory was itself so small that the Astronomer Royal, with a single assistant, sufficed for the entire work. Everything, therefore, depended upon the ability, energy, and character of the actual director. There was no large organized staff, established routine, or official tradition, to keep the institution moving on certain lines, irrespective of the personal qualities of the chief. It was specially fortunate, therefore, that the first four Astronomers Royal, Flamsteed, Halley, Bradley, and Maskelyne (for Bliss, the immediate successor of Bradley, reigned for so short a time that he may be practically left out of the count), were all men of the most conspicuous ability.

It will be convenient to divide the history of the first seven Astronomers Royal into three sections. In the first, we have the founder, John Flamsteed, a pathetic and interesting figure, whom we seem to know with especial clearness, from the fulness of the memorials which he has left to us. He was succeeded by the man who was, indeed, best fitted to succeed him, but whom he most hated. The second to the sixth Astronomers Royal formed what we might almost speak of as a dynasty, each in turn nominating his successor, who had entered into more or less close connection with the Observatory during the lifetime of the previous director; and the lives of these five may well form the second section. The line was interrupted after the resignation of the sixth Astronomer Royal, and the third section will be devoted to the seventh director, Airy, under whom the Observatory entered upon its modern period of expansion.

'God suffers not man to be idle, although he swim in the midst of delights; for when He had placed His own image (Adam) in a paradise so replenished (of His goodness) with varieties of all things, conducing as well to his pleasure as sustenance, that the earth produced of itself things convenient for both—He yet (to keep him out of idleness) commands him to till, prune, and dress his pleasant, verdant habitation; and to add (if it might be) some lustre, grace, or conveniency to that place, which, as well as he, derived its original from his Creator.'

In these words John Flamsteed begins the first of several autobiographies which he has handed down to us; this particular one being written before he attained his majority, 'to keep myself from idleness and to recreate myself.'

'I was born,' he goes on, 'at Denby, in Derbyshire, in the year 1646, on the 19th day of August, at 7 hours 16 minutes after noon. My father, named Stephen, was the third son of Mr. William Flamsteed, of Little Hallam; my mother, Mary, was the daughter of Mr. John Spateman, of Derby, ironmonger. From these two I derived my beginning, whose parents were of known integrity, honesty, and fortune, as they [were] of equal extraction and ingenuity; betwixt whom I [was] tenderly educated (by reason of my natural weakness, which required more than ordinary care) till I was aged three years and a fortnight; when my mother departed, leaving my father a daughter, then not a month old, with me, then weak, to his fatherly care and provision.'

The weakly, motherless boy became at an early age a voracious reader. At first, he says—

'I began to affect the volubility and ranting stories of romances; and at twelve years of age I first left off the wild ones, and betook myself to read the better sort of them, which, though they were not probable, yet carried no seeming impossibility in the fiction. Afterwards, as my reason increased, I gathered other real histories; and by the time I was fifteen years old I had read, of the ancients, Plutarch's Lives, Appian's and Tacitus's Roman Histories, Holingshed's History of the Kings of England, Davies's Life of Queen Elizabeth, Saunderson's of King Charles the First, Heyling's Geography, and many others of the moderns; besides a company of romances and other stories, of which I scarce remember a tenth at present.'

Flamsteed received his education at the free school at Derby, where he continued until the Whitsuntide of 1662, when he was nearly sixteen years of age. Two years earlier than this, however, a great misfortune fell upon him.

'At fourteen years of age,' he writes, 'when I was nearly arrived to be the head of the free-school, [I was] visited with a fit of sickness, that was followed with a consumption and other distempers, which yet did not so much hinder me in my learning, but that I still kept my station till the form broke up, and some of my fellows went to the Universities; for which, though I was designed, my father thought it not advisable to send me, by reason of my distemper.'

This was a keen disappointment to him, but seems to have really been the means of determining his career. The sickly, suffering boy could not be idle, though 'a day's short reading caused so violent a headache;' and a month or two after he had left school, he had a book lent to him—Sacrobosco's De Sphæra, in Latin—which was the beginning of his mathematical studies. A partial eclipse of the sun in September of the same year seems to have first drawn his attention to astronomical observation, and during the winter his father, who had himself a strong passion for arithmetic, instructed him in that science.

It was astonishing how quickly his appetite for his new subjects grew. The Art of Dialling, the calculation of tables of the sun's altitudes for all hours of the day, and for different latitudes, and the construction of a quadrant—'of which I was not meanly joyful'—were the occupations of this winter of illness.

In 1664 he made the acquaintanceship of two friends, Mr. George Linacre and Mr. William Litchford; the former of whom taught him to recognize many of the fixed stars, whilst the latter was the means of his introduction to a knowledge of the motions of the planets.

'I had now completed eighteen years, when the winter came on, and thrust me again into the chimney; whence the heat and dryness of the preceding summer had happily once before withdrawn me.'

The following year, 1665, was memorable to him 'for the appearance of the comet,' and for a journey which he made to Ireland to be 'stroked' for his rheumatic disorder by Valentine Greatrackes, a kind of mesmerist, who had the repute of effecting wonderful cures. The journey, of which he gives a full and vivid account, occupied a month; but though he was a little better, the following winter brought him no permanent benefit.

But, ill or well, he pressed on his astronomical studies. A large partial eclipse of the sun was due the following June; he computed the particulars of it for Derby, and observed the eclipse itself to the best of his ability. He argued out for himself 'the equation of time'; the difference, that is, between time as given by the actual sun, or 'apparent time,' and that given by a perfect clock, or 'mean time.' He drew up a catalogue of seventy stars, computing their right ascensions, declinations, longitudes, and latitudes for the year 1701; he attempted to determine the inclination of the ecliptic, the mean length of the tropical year, and the actual distance of the earth from the sun. And these were the recreations of a sickly, suffering young man, not yet twenty-one years of age, and who had only begun the study of arithmetic, such as fractions and the rule of three, four years previously!

His next attempt was almanac-making, in the which he improved considerably upon those current at the time. His almanac for 1670 was rejected, however, and returned to him, and, not to lose his whole labour, he sent his calculations of an eclipse of the sun, and of five occultations of stars by the moon, which he had undertaken for the almanac, to the Royal Society. He sent the paper anonymously, or, rather, signed it with an anagram, 'In mathesi a sole fundes,' for 'Johannes Flamsteedius.' His covering letter ends thus:—

'Excuse, I pray you, this juvenile heat for the concerns of science and want of better language, from one who, from the sixteenth year of his age to this instant, hath only served one bare apprenticeship in these arts, under the discouragement of friends, the want of health, and all other instructors except his better genius.'

This letter was dated November 4, 1669, and on January 14, Mr. Oldenburg, the secretary of the Society, replied to him in a letter which the young man cannot but have felt encouraging and flattering to the highest degree.

'Though you did what you could to hide your name from us,' he writes, 'yet your ingenious and useful labours for the advancement of Astronomy addressed to the noble President of the Royal Society, and some others of that illustrious body, did soon discover you to us, upon our solicitous inquiries after their worthy author.'

And after congratulating him upon his skill, and encouraging him to furnish further similar papers, he signs himself, 'Your very affectionate friend and real servant'—no unmeaning phrase, for the friendship then commenced ceased only with Oldenburg's life.

The following June, his father, pleased with the notice that some of the leading scientific men of the day were taking of his son, sent him up to London, that he might be personally acquainted with them; and he then was introduced to Sir Jonas Moore, the Surveyor of the Ordnance, who made him a present of Townley's micrometer, and promised to furnish him with object-glasses for telescopes at moderate rates.

On his return journey he called at Cambridge, where he visited Dr. Barrow and Newton, and entered his name in Jesus College.

It was not until the following year, 1671, that he was enabled to complete his own observatory, as he had had to wait long for the lenses which Sir Jonas Moore and Collins had promised to procure for him. He still laboured under several difficulties, in that he had no good means for measuring time, pendulum clocks not then being common. He, therefore, with a practical good sense which was characteristic, refrained from attempting anything which lay out of his power to do well, and he devoted himself to such observations as did not require any very accurate knowledge of the time. At the same time, he was careful to ascertain the time of his observations as closely as possible, by taking the altitudes of the stars.

The next four years seem to have passed exceedingly pleasantly to him. The notes of ill-health are few. He was making rapid progress in his acquaintanceship with the work of other astronomers, particularly with those of the three marvellously gifted young men—Horrox, Crabtree, and Gascoigne—who had passed away shortly before his own birth. He was making new friends in scientific circles, and, in particular, Sir Jonas Moore was evidently esteeming him more and more highly. In 1674 he became more intimate with Newton, the occasion which led to this acquaintanceship being the amusing one, that his assistance was asked by Newton, who had found himself unable to adjust a microscope, having forgotten its object-glass—not the only instance of the great mathematician's absent-mindedness.

The same year he took his degree of A.M. at Cambridge, designing to enter the Church; but Sir Jonas Moore was extremely anxious to give him official charge of an observatory, and was urging the Royal Society to build an astronomical observatory at Chelsea College, which then belonged to that body. He therefore came up to London, and resided some months with Sir Jonas Moore at the Tower. But shortly after his coming up to London, 'an accident happened,' to use his own expression, that hastened, if it did not occasion, the building of Greenwich Observatory.

'A Frenchman that called himself Le Sieur de St. Pierre, having some small skill in astronomy, and made an interest with a French lady, then in favour at Court, proposed no less than the discovery of the Longitude, and had procured a kind of Commission from the King to the Lord Brouncker, Dr. Ward (Bishop of Salisbury), Sir Christopher Wren, Sir Charles Scarborough, Sir Jonas Moore, Colonel Titus, Dr. Pell, Sir Robert Murray, Mr. Hook, and some other ingenious gentlemen about the town and Court, to receive his proposals, with power to elect, and to receive into their number, any other skilful persons; and having heard them, to give the King an account of them, with their opinion whether or no they were practicable, and would show what he pretended. Sir Jonas Moore carried me with him to one of their meetings, where I was chosen into their number; and, after, the Frenchman's proposals were read, which were:

'(1) To have the year and day of the observations.

'(2) The height of two stars, and on which side of the meridian they appeared.

'(3) The height of the moon's two limbs.

'(4) The height of the pole—all to degrees and minutes.

'It was easy to perceive, from these demands, that the sieur understood not that the best lunar tables differed from the heavens; and that, therefore, his demands were not sufficient for determining the longitude of the place where such observations were, or should be, made, from that to which the lunar tables were fitted, which I represented immediately to the company. But they, considering the interests of his patroness at Court, desired to have him furnished according to his demands. I undertook it; and having gained the moon's true place by observations made at Derby, February 23, 1672, and November 12, 1673, gave him observations such as he demanded. The half-skilled man did not think they could have been given him, and cunningly answered "They were feigned." I delivered them to Dr. Pell, February 19, 1674–5, who, returning me his answer some time after, I wrote a letter in English to the commissioners, and another in Latin to the sieur, to assure him they were not feigned, and to show them that, if they had been, yet if we had astronomical tables that would give us the two places of the fixed stars and the moon's true places, both in longitude and latitude, nearer than to half a minute, we might hope to find the longitude of places by lunar observations, but not by such as he demanded. But that we were so far from having the places of the fixed stars true, that the Tychonic Catalogues often erred ten minutes or more; that they were uncertain to three or four minutes, by reason that Tycho assumed a faulty obliquity of the ecliptic, and had employed only plain sights in his observations: and that the best lunar tables differ one-quarter, if not one-third, of a degree from the heavens; and lastly, that he might have learnt better methods than he proposed, from his countryman Morin, whom he had best consult before he made any more demands of this nature.'

This was in effect to tell St. Pierre that his proposal was neither original nor practicable. If St. Pierre had but consulted Morin's writings (Morin himself had died more than eighteen years before), he would have known that practically the same proposal had been laid before Cardinal Richelieu in 1634, and had been rejected, as quite impracticable in the then state of astronomical knowledge. Possibly Flamsteed meant further to intimate that St. Pierre had simply stolen his method from Morin, hoping to trade it off upon the government of another country; in which case he would no doubt regard Flamsteed's letter as a warning that he had been found out.

Flamsteed continues:—

'I heard no more of the Frenchman after this; but was told that, my letters being shown King Charles, he startled at the assertion of the fixed stars' places being false in the catalogue; said, with some vehemence, "He must have them anew observed, examined, and corrected, for the use of his seamen;" and further (when it was urged to him how necessary it was to have a good stock of observations taken for correcting the motions of the moon and planets), with the same earnestness, "he must have it done." And when he was asked Who could, or who should do it? "The person (says he) that informs you of them." Whereupon I was appointed to it, with the incompetent allowance aforementioned; but with assurances, at the same time, of such further additions as thereafter should be found requisite for carrying on the work.'