--_Translator"s Note_.

BAILLY A MEMBER OF THE ACADEMY OF SCIENCES.--HIS RESEARCHES ON JUPITER"S SATELLITES.

Bailly was named member of the Academy of Sciences the 29th January, 1763. From that moment his astronomical zeal no longer knew any bounds.

The laborious life of our fellow-academician might, on occasion, be set up against a line, more fanciful than true, by which an ill-natured poet stigmatized academical honours. Certainly no one would say of Bailly, that after his election,

"Il s"endormit et ne fit qu"un somme."

"He fell asleep and made but one nap (or sum)."

On the contrary, we cannot but be surprised at the mult.i.tude of literary and scientific labours that he accomplished in a few years.

Bailly"s earliest researches on Jupiter"s satellites began in 1763.

The subject was happily chosen. Studying it in all its generalities, he showed himself both an indefatigable computer, a clear-sighted geometer, and an industrious and able observer. Bailly"s researches on the satellites of Jupiter, will always be his first and chief claim to scientific glory. Before him, the Maraldis, the Bradleys, the Wargentins had discovered empirically some of the princ.i.p.al perturbations that those bodies undergo, in their revolving motions around the powerful planet that rules them; but they had not been traced up to the principles of universal attraction. The initiative honour in this respect belongs to Bailly. Nor is this honour decreased by the ulterior and considerable improvements that the science has since received; even the discoveries of Lagrange and of Laplace have left this honour intact.

The knowledge of the satellitic motions rests almost entirely on the observation of the precise moment when each of those bodies disappears, by entering into the conical shadow, which the immense opaque globe of Jupiter projects on the opposite side from the sun. In the course of discussing a mult.i.tude of these eclipses, Bailly was not long in perceiving that the computers of the Satellitic Tables worked on numerical data that were not at all comparable with each other. This seemed of little consequence previous to the birth of the theory; but, after the a.n.a.lytical discovery of the perturbations, it became desirable to estimate the possible errors of observation, and to suggest means for remedying them. This was the object of the very considerable work that Bailly presented to the Academy in 1771.

In this beautiful memoir, the ill.u.s.trious astronomer developes the series of experiments, by the aid of which each observation may give the instant of the real disappearance of a satellite, distinguished from the instant of the apparent disappearance, whatever be the power of the telescope used, whatever be the alt.i.tude of the eclipsed body above the horizon, and consequently, whatever be the transparency of the atmospheric strata through which the phenomenon is observed, also whatever be the distance from that body to the sun, or to the planet; finally, whatever be the sensibility of the observer"s sight, all which circ.u.mstances considerably influence the time of apparent disappearance.

The same series of ingenious and delicate observations led the author, very curiously, to the determination of the true diameters of the satellites, that is to say, of small luminous points, which, with the telescopes then in use, showed no perceptible diameter.

I will rest contented with these general considerations; only remarking, in addition, that the diaphragms used by Bailly were not intended only to diminish the quant.i.ty of light contributing to the formation of the images, but that they considerably increase the diameter, and in a variable way, at least in the instance of stars.

Under this new aspect, it will be requisite to submit the question to a new examination.

Any geometers and astronomers who wish to know all the extent of Bailly"s labours, must not content themselves with consulting the collections in the Academy of Sciences; for he published, at the beginning of 1766, a separate work under the modest t.i.tle of _Essay on the Theory of Jupiter"s Satellites_.

The author commences with the _Astronomical History of the Satellites_.

This history contains an almost complete a.n.a.lysis of the discoveries by Maraldi, by Bradley, by Wargentin. The labours of Galileo and his contemporaries are given with less detail and exactness. I have thought that I ought to fill up the lacunae, by availing myself of some very precious doc.u.ments published a few years since, and which were unknown to Bailly.

But this I will do in a separate notice, free from all preconceived ideas, and free from all party spirit; I will not forget that an honest man ought not to calumniate any one, not even the agents of the Inquisition.

BAILLY"S LITERARY WORKS.--HIS BIOGRAPHIES OF CHARLES V.--OF LEIBNITZ--OF PETER CORNEILLE--OF MOLIeRE.

When Bailly entered the Academy of Sciences, the perpetual secretary was Grandjean de Fouchy. The bad health of this estimable scholar occasioned an early vacancy to be foreseen. D"Alembert cast his views on Bailly, hinted to him the survivorship to Fouchy, and proposed to him, by way of preparing the way, to write some biographies. Bailly followed the advice of the ill.u.s.trious geometer, and chose as the subject of his studies, the eloges proposed by several academies, though princ.i.p.ally by the French Academy.

From the year 1671 to the year 1758, the prize subjects proposed by the French Academy related to questions of religion and morality. The eloquence of the candidates had therefore had to exercise itself successively on the knowledge of salvation; on the merit and dignity of martyrdom; on the purity of the soul and of the body; on the danger there is in certain paths that appear safe, &c. &c. It had even to paraphrase the _Ave Maria_. According to the literal intentions of the founder, (Balzac,) each discourse was ended by a short prayer. Duclos thought in 1758, that five or six volumes of similar sermons must have exhausted the matter, and on his proposal the Academy decided that, in future, it would give as the subject of the eloquence prize, the eulogiums of the great men of the nation. Marshal Saxe, Duguay Trouin, Sully, D"Aguesseau, Descartes, figured first on this list. Later, the Academy felt itself authorized to propose the eloge of kings themselves; it entered on this new branch at the beginning of 1767, by asking for the eloge of Charles V.

Bailly entered the lists, but his essay obtained only an honourable mention.

Nothing is more instructive than to search out at what epoch originated the principles and opinions of persons who have acted an important part on the political scene, and how those opinions developed themselves. By a fatality much to be regretted, the elements of these investigations are rarely numerous or faithful. We shall not have to express these regrets relative to Bailly. Each composition shows us the serene, candid, and virtuous mind of the ill.u.s.trious writer, in a new and true point of view. The eloge of Charles V. was the starting point, followed by a long series of works, and it ought to arrest our attention for a while.

The writings, crowned with the approbation of the French Academy, did not reach the public eye till they had been submitted to the severe censure of four Doctors in Theology. A special and digested approbation by the high dignitaries of the Church, whom the ill.u.s.trious a.s.sembly always possessed among her members, was not a sufficient subst.i.tute for the humbling formality. If we are sure that we possess the eloge of Charles V. such as it flowed from the author"s pen; if we have not reason to fear that the thoughts have undergone some mutilation, we owe it to the little favour that the discourse of Bailly enjoyed in the sitting of the Academy in 1767. Those thoughts, however, would have defied the most squeamish mind, the most shadowy susceptibility. The panegyrist unrolls with emotion the frightful misfortunes that a.s.sailed France during the reign of King John. The temerity, the improvidence of that monarch; the disgraceful pa.s.sions of the King of Navarre; his treacheries; the barbarous avidity of the n.o.bility; the seditious disposition of the people; the sanguinary depredations of the great companies; the ever recurring insolence of England; all this is expressed without disguise, yet with extreme moderation. No trait reveals, no fact even foreshadows in the author, the future President of a reforming National a.s.sembly, still less the Mayor of Paris, during a revolutionary effervescence. The author may make Charles V. say that he will discard favour, and will call in renown to select his representatives; it will appear to him that taxes ought to be laid on riches and spared on poverty; he may even exclaim that oppression awakens ideas of equality. His temerity will not overleap this boundary.

Bossuet, Ma.s.sillon, Bourdaloue, made the Chair resound with bold words of another description.

I am far from blaming this scrupulous reserve; when moderation is united to firmness, it becomes power. In a word, however, Bailly"s patriotism might, I was about to say ought to, have shown itself more susceptible, more ardent, prouder. When in the elegant prosopopoeia which closes the eloge, the King of England has recalled with arrogance the fatal day of Poitiers, ought he not instantly to have restrained that pride within just limits? ought he not to have cast a hasty glance on the components of the Black Prince"s army? to examine whether a body of troops, starting from Bordeaux, recruiting in Guienne, did not contain more Gascons than English? whether France, now bounded by its natural limits, in its magnificent unity, would not have a right, every thing being examined, to consider that battle almost as an event of civil war? ought he not, in short, to have pointed out, in order to corroborate his remarks, that the knight to whom King John surrendered himself, Denys de Morbecque, was a French officer banished from Artois?

Self-reliance on the field of battle is the first requisite for obtaining success; now, would not our self-reliance be shaken, if the men most likely to know the facts, and to appreciate them wisely, appeared to think that the Frank race were nationally inferior to other races who had peopled this or that region, either neighbouring or distant? This, let it be well remarked, is not a puerile susceptibility.

Great events may, on a given day, depend on the opinion that the nation has formed of itself. Our neighbours on the other side of the Channel, afford examples on this subject that it would be well to imitate.

In 1767, the Academy of Berlin proposed a prize for an eloge of Leibnitz. The public was somewhat surprised at it. It was generally supposed that Leibnitz had been admirably praised by Fontenelle, and that the subject was exhausted. But from the moment that Bailly"s essay, crowned in Prussia, was published, former impressions were quite changed. Every one was anxiously a.s.serting that Bailly"s appreciation of his subject might be read with pleasure and benefit, even after Fontenelle"s. The eloge composed by the historian of Astronomy will not, certainly, make us forget that written by the first Secretary of the Academy of Sciences. The style is, perhaps, too stiff; perhaps it is also rather declamatory; but the biography, and the a.n.a.lysis of his works, are more complete, especially if we consider the notes; the _universal_ Leibnitz is exhibited under more varied points of view.

In 1768, Bailly obtained the award of the prize of eloquence proposed by the Academy of Rouen. The subject was the eloge of Peter Corneille.

In reading this work of our fellow-academician, we may be somewhat surprised at the immense distance that the modest, the timid, the sensitive Bailly puts between the great Corneille, his special favourite, and Racine.

When the French Academy, in 1768, proposed an eloge of Moliere for compet.i.tion, our candidate was vanquished only by Chamfort. And yet, if people had not since that time treated of the author of "Tartufe" to satiety, perhaps I would venture to maintain, notwithstanding some inferiority of style, that Bailly"s discourse offered a neater, truer, and more philosophic appreciation of the princ.i.p.al pieces of that immortal poet.

DEBATES RELATIVE TO THE POST OF PERPETUAL SECRETARY OF THE ACADEMY OF SCIENCES.

We have seen D"Alembert, ever since the year 1763, encouraging Bailly to exercise himself in a style of literary composition then much liked, the style of eloge, and holding out to him in prospect the situation of Perpetual Secretary of the Academy of Sciences. Six years after, the ill.u.s.trious geometer gave the same advice, and perhaps held out the same hopes, to the young Marquis de Condorcet. This candidate, docile to the voice of his protector, rapidly composed and published the eloges of the early founders of the Academy, of Huyghens, of Mariotte, of Roemer, &c.

At the beginning of 1773, the Perpetual Secretary, Grandjean de Fouchy, requested that Condorcet should be nominated his successor, provided he survived him. D"Alembert strongly supported this candidateship. Buffon supported Bailly with equal energy; the Academy presented for some weeks the aspect of two hostile camps. There was at last a strongly disputed electoral battle; the result was the nomination of Condorcet.

I should regret if we had to judge of the sentiments of Bailly, after this defeat, by those of his adherents. Their anger found vent in terms of unpardonable asperity. They said that D"Alembert had "basely betrayed friendship, honour, and the first principles of probity."

They here alluded to a promise of protection, support, cooperation, dating ten years back. But was his promise absolute? Engaging himself personally to Bailly for a situation that might not become vacant for ten or fifteen years, had D"Alembert, contrary to his duty as an academician, declared beforehand, that any other candidate, whatever might be his talents, would be to him as not existing?

This is what ought to have been ascertained, before giving themselves up to such violent and odious imputations.

Was it not quite natural that the geometer D"Alembert, having to p.r.o.nounce his opinion between two honourable learned men, gave the preference to the candidate who seemed to him most imbued with the higher mathematics? The eloges of Condorcet were, besides, by their style, much more in harmony with those that the Academy had approved during three quarters of a century. Before the declaration of the vacancy on the 27th of February, 1773, D"Alembert said to Voltaire, relative to the recueil by Condorcet, "Some one asked me the other day what I thought of that work. I answered by writing on the frontispiece, "Justice, propriety, learning, clearness, precision, taste, elegance, and n.o.bleness."" And Voltaire wrote, on the 1st of March, "I have read, while dying, the little book by M. de Condorcet; it is as good in its departments as the eloges by Fontenelle. There is a more n.o.ble and more modest philosophy in it, though bold."

And excitement in words and action could not be legitimately reproached in a man who had felt himself supported by a conviction of such distinct and powerful influence.

Among the eloges by Bailly, there is one, that of the Abbe de Lacaille, which not having been written for a literary academy, shows no longer any trace of inflation or declamation, and might, it seems to me, compete with some of the best eloges by Condorcet. Yet, it is curious, that this excellent biography contributed, perhaps as much as D"Alembert"s opposition, to make Bailly"s claims fail. Vainly did the celebrated astronomer flatter himself in his exordium, "that M. de Fouchy, who, as Secretary of the Academy, had already paid his tribute to Lacaille, would not be displeased at his having followed him in the same career ... that he would not be blamed for repeating the praises due to an ill.u.s.trious man."

Bailly, in fact, was not blamed aloud; but when the hour for retreat had sounded in M. de Fouchy"s ear, without any fuss, without showing himself offended in his self-love, remaining apparently modest, this learned man, in asking for an a.s.sistant, selected one who had not undertaken to repeat his eloges; who had not found his biographies insufficient. This preference ought not to be, and was not, uninfluential in the result of the compet.i.tion.

Bailly, if Perpetual Secretary of the Academy, would have been obliged to reside constantly at Paris. But Bailly, as member of the Astronomical Section, might retire to the country, and thus escape those thieves of time, as Byron called them, who especially abound in the metropolis.

Bailly settled at Chaillot. It was at Chaillot that our fellow-academician composed his best works, those that will sail down the stream of time.

Nature had endowed Bailly with the most happy memory. He did not write his discourses till he had completed them in his head. His first copy was always a clean copy. Every morning Bailly started early from his humble residence at Chaillot; he went to the Bois de Boulogne, and there, walking for many hours at a time, his powerful mind elaborated, coordinated, and robed in all the pomps of language, those high conceptions destined to charm successive generations. Biographers inform us that Crebillon composed in a similar way. And this was, according to several critics, the cause of the incorrectness, of the asperity of style, which disfigure several pieces by that tragic poet. The works of Bailly, and especially the discourses that complete the _History of Astronomy_, invalidate this explanation. I could also appeal to the elegant and pure productions of that poet whom France has just lost and weeps for. No one indeed can be ignorant of his works; Casimir Delavigne, like Bailly, never committed his verses to paper until he had worked them up in his mind to that harmonious perfection which procured for them the unanimous suffrages of all people of taste. Gentlemen, pardon this reminiscence. The heart loves to connect such names as those of Bailly and of Delavigne; those rare and glorious symbols, in whom we find united talent, virtue, and an invariable patriotism.

HISTORY OF ASTRONOMY.--LETTERS ON THE ATLANTIS OF PLATO AND ON THE ANCIENT HISTORY OF ASIA.

In 1775, Bailly published a quarto volume, ent.i.tled _History of Ancient Astronomy, from its Origin up to the Establishment of the Alexandrian School_. An a.n.a.logous work for the lapse of time, comprised between the Alexandrian School and 1730, appeared in 1779, in two volumes. An additional volume appeared three years later, ent.i.tled the _History of Modern Astronomy up to the Epoch of 1782_. The fifth part of this immense composition, the _History of Indian Astronomy_, was published in 1787.

When Bailly undertook this general history of Astronomy, the science possessed nothing of the sort. Erudition had seized upon some special questions, some detailed points, but no commanding view had presided over these investigations.