Respecting the New Planet Neptune. 241 that date, yet the sole honour of their discovery has been universally assigned to Huygens. The great truth concealed in the anagram was then displayed in this remarkable sentence :— "Annulo cingitur, tenui, plano, nusquam cohærente ad eclipticum inclinato,"* He is surrounded with a ring, thin, plane, nowhere adhering, and inclined to the ecliptic, -a sentence which, though concealed in its unmeaning elements for more than three years, has preserved for Huygens the date and glory of his discovery, as effectually as if he had proclaimed it with a trumpet tongue, or published it in all the Gazettes of Europe. In the discussions relative to the discovery of the law of Refraction-doubtless one of the most important in optical science -the claim of Descartes, founded on priority of publication, has been universally disallowed. Willebrord Snellius, a young geometer of high merit, who filled the chair of mathematics at Leyden, had discovered the true law of refraction, previous to his death in 1626. He never even communicated his discovery, in so far as we know, to his friends, and still less to the public; and the very words in which it is recorded have never been published. The evidence of his prior claim rests on the testimony of Hortensius, Huygens, and others who had seen the MSS.; and though Descartes gave a trigonometrical form to the expression of the law, by substituting the ratio of the sines in place of what we regard as the more beautiful ratio given by Snellius, and had the advantage of being the first to publish to all the great discovery, yet the scientific world, which received the benefit of it, has unanimously, or rather with one exception, namely that of Biot, transferred the undivided honour of the discovery to the Dutch philosopher. The historians of science, Montucla, Bossut, Priestley, Playfair, and Whewell,-and the distinguished philosophers Huygens, David Gregory, Muschenbroek, Smith, Robi son, Hutton, and Dr. Young, have all concurred in placing the valued laurel on the brow of Snellius.-Here, then, we have a jury which time has impannelled from all nations and from every period of modern science-a jury distinguished by personal honour and exalted genius, promulgating to the world their unani mous decision, that priority of discovery, even when that discovery has neither been communicated to friends nor published to the world, supersedes the claims of priority of publication. Had Mr. Adams died in October 1845, and left to posterity only the legacy of his researches, or merely the scrap of paper which con VOL. VII. * HUGENII, Opera Varia. Syst. Saturn, pr. 526, 566. tained the place of the new Planet, and the elements of its orbit, the jury whom we have named, would have hailed him as the discoverer, and honoured him with the prize. The celebrated dispute between Newton and Leibnitz, respecting the invention of the method of Fluxions, or the Differential Calculus, furnishes us with new arguments against the heresy in scientific law, which we have been combating. That Newton was in possession of the method of fluxions so early as 1665, is now generally admitted, though the truth of the fact rests on the testimony of individual witnesses, to whom he intrusted it in confidence. He refused to publish his methods to the world, because he had not perfected them; but, in order to fix the date of his discovery, he communicated to Leibnitz, through Oldenburg, the fact, that he was in the possession of a generalmethod of drawing tangents, which is the method of fluxions; but he concealed the method in two anagrams. In two or three months after Leibnitz could have received this letter, namely on the 21st June 1677, Leibnitz sent to Newton the principles of his differential calculus, but he did not publish his method till the year 1684, when it appeared in the Leipsic Acts. Now, Newton's claim to priority of discovery rests, not on publication, but on communication to his friends, and to Leibnitz in his anagrams; and the date of Leibnitz's independent discovery, as we believe it to be, of the differential calculus, is universally acknowledged to be that of his letter to Newton in 1677, and not that of his paper in the Leipsic Acts for 1684. Hence it appears, that in those palmy days of mathematical discovery, the doctrine of fixing dates by publication to the world was absolutely unknown, and would have been universally rejected. The date of an anagram was sufficient; and had Leibnitz transmitted his differential calculus in an anagram to Newton previous to 1655, and had never published a word on the subject, his claim to priority of discovery would have been universally conceded to him. If, on the other hand, priority of publication to the world is held to supersede priority of invention, then must we draw the conclusion, which has never yet been drawn, that Leibnitz has the undivided honour of being the first discoverer of the new calculus. Had Mr. Adams, therefore, published his great discovery in an anagram in October 1845, without communicating it to a single friend, the date of that anagram would have been the date of his discovery, and would have excluded all future claimants. The disadvantages of the Anagram as a secret receptacle for scientific truth, must have been long ago perceived; and we believe, it has been seldom, if ever, used either in the last or the present century. Should the philosopher who uses it, die without Respecting the New Planet Neptune. 243 having committed his discovery to writing, no ingenuity could res cue it from its alphabetic tomb; and while he thus became a loser in fame, the public would become a loser in knowledge. But, independent of this objection, there are many discoveries and inventions which could neither be properly represented nor satisfactorily reproduced by the transposition of any considerable number of letters. The omission or the addition of a letter might alter or destroy the meaning of the whole, and by thus throwing discord among a mob of letters, might occasion that very breach of the peace which the anagram was intended to prevent. Men of science were, on grounds doubtless like these, led to adopt other methods of fixing the date of their discoveries, when their publication to the world would have been either inconvenient or premature. On some occasions they have communicated their results confidentially in letters to a friend-or exhibited and explained them to one or more credible witnesses or read them to a philosophical society-or had them signed by office-bearers of the same body-or taught them to pupils or promulgated them in lectures or recorded them in a manuscript journal.* In all these methods, except the last, the evidence may be so complete as to place the fact of priority beyond a doubt, and entitle the claimant to all the rights of original discovery. But the most efficacious of all methods, and the one actually adopted in modern times, is, to consign the discovery in a sealed packet, which is deposited at a registered date in the archives of a philosophical society. The first germ of an important discovery is thus preserved from those who lie in wait for ideas, and pursue the game started by another. The author follows at his leisure the train of research into which it may lead him, till he has completed his investigations, and is ready to publish them to the world. This mode of fixing the date of a discovery has been frequently adopted in this country. We cannot say how often, or in what precise form it has been done; but we have had occasion to know that sealed packets of this kind have been deposited in the archives of the Royal Society of London by Professor Faraday, Professor Wheatstone, and Sir David Brewster; and it is well known that similar packets, paquets cachetés, are deposited with the same object, and almost weekly, in the archives of the Academy of Sciences of Paris, both by members of the Institute and by other individuals who may transmit them in conformity with the rules of the Academy. This method is in such high estimation in France that it has been reduced to a regular system, and * This method of fixing a date is the least satisfactory of all, because it is always possible that a forgery may be committed. It was tried and rejected in the Watt and Cavendish Controversy. See this Journal, vol. vi. p. 493. so extensively is it adopted, that in the year 1845 no fewer than seventy, and in 1846 no fewer than ninety paquets cachetés were deposited with due formality in the archives of the Institute. The sealed packet, bearing the author's name, is forwarded or delivered to the secretary. It is laid before the Academy and accepted, and its acceptance is recorded in their minutes, and published in the Comptes Rendus, &c. When the author wishes it to be opened, its opening is authorized by the Academy, and it is opened and read in their be withdrawn presence; or it may when the author has published the invention and discovery which it contains. In order to illustrate the operation and effect of these sealed packets, let us suppose that M. Biot had deposited one on the 1st January 1846, containing the fine discovery of Professor Faraday on the action of a magnet in producing the structure which gives circular polarization, and that Professor Faraday had made the same discovery six months later, and published it on the 1st of June of the same year. Is there a philosopher in Europe, beyond the pale of French or English feeling, that would not have hailed M. Biot as the first discoverer, and pre-eminently entitled to all the honours of original genius? Is there a patriot in France, justly proud of the scientific renown of his country, that would not have denounced the rapacity of England, had she claimed the glory of the discovery? And is there a philosopher in Britain-we know there is none-who would have dared to challenge the immutable truth that it was to a foreign sage that nature surrendered her secret, and that none but he could wear the laurel which was won? If we now substitute the name of Adams for that of Biot, and the name of Le Verrier for that of Faraday, the same questions must receive the same answers, whether they be asked in France, in England, or throughout the civilized world. Such are the facts, and such the arguments upon which we rest our conclusion-that Mr. Adams was the first discoverer of the new planet;-that he is entitled to all the honour and advantages of an original discoverer;-that he actually published his results to such an extent as to give the public the full benefit of his labours, and that his merit would not have been lessened nor his rights affected had he concealed his discovery in an anagram, or swathed it the bandages of a sealed packet. As we have striven with some anxiety to state the facts of this important case with all the correctness which we could attain, and to judge of it without personal or national prepossessions, we feel assured that we have impressed our own opinions upon our readers, and we confidently trust that the astronomers and philosophers of other lands will concede to truth her rigorous demands -to Mr. Adams his inalienable rights-and to Cambridge the Respecting the New Planet Neptune. 245 well-merited glory of being the intellectual birth-place of her second Newton. These concessions have to a certain extent been already made. The authority to give a name to the planet, so prematurely transferred from M. Le Verrier to M. Arago;-the resolution of the latter to call it by no other name than that of Le Verrier-and the determination of both to facilitate the adoption of this name by changing the name of Uranus to Herschel, have produced an effect upon the minds of European astronomers, the very reverse of what was expected. A resolution, almost unanimous, has been taken to adopt the name of Neptune, first chosen by Le Verrier. Mr. Adams, Professor Challis, and the Astronomer-Royal, in England, the astronomers of Italy, and, as the celebrated Encke informs us, the first astronomical authorities in Germany and Russia, have pronounced in favour of the name; and in a letter addressed to Professor Challis by M. Struve, the distinguished astronomer of Poulkova, he has given the following noble and disinterested testimony to the priority and merit of Mr. Adams :-" The Poulkova astronomers have resolved to maintain the name of Neptune, in the opinion that the name of Le Verrier would be against the accepted analogy, and against historical truth, as it cannot be denied that Mr. Adams has been the first theoretical discoverer of that body, though not so happy (fortunate) as to effect a direct result of his indications." The nature and object of this article have necessarily led us to speak more of the labours of Mr. Adams than of those of M. Le Verrier, and the discussions which it contains may be viewed by a careless or a prejudiced reader as depreciatory of the merits of the French Geometer. If such a sentiment has found its way into the minds of any of our readers-we disavow it as ours, and deprecate it if it be theirs. Our esteem for M. Le Verrier, and our admiration of his genius, cannot be affected by the issue of a controversy in which neither his honour nor his talents are impugned. The originality and independence of his researches have never been questioned. In the records of fame, his name will stand beside that of Mr. Adams, and will never be dissociated from the planet which they intellectually discovered. We lament the collision of gigantic minds, even when personal interests and feelings are alone concerned. We lament it more when national passions gather round the contest, embittering its dialectics and procrastinating its settlement. But there is always this consolation in the intellectual warfare, that however furious be the onset, and violent the shock, the conflicting elements can neither be crushed nor destroyed. Truth springs purer from her ordeal however fiery, and, like the storm-lashed oak, stands firmer on a once tottering pedestal. |