They Told The Story
A Neptune Chronology
Adams Dated Computations
The Forgotten Diary
Within One Degree
The Crown Jewels Document
Announcing The Discovery
Challis' Unseen Testimony
A Retrospective History
A Cantab. Clique
Adam's July Ephemeris
Mapless In Cambridge
Airy Tells the Truth
The Radius Vector: A Trivial Question?
Airy Blows His Top
Eggen Takes the Papers
Selected Correspondence
Primary Sources
Related Links.

 

SELECTED EXCERPTS OF CORRESPONDENCE,
CONCERNING THE DISCOVERY OF NEPTUNE

Selected Excerpts of correspondence,

McA the McAlister collection, kept in the JCA, -transcript of J.C.Adams material.
RGO Royal Greenwich Observatory’s Neptune file, at the UL, Cambridge
IoA Institute of Astronomy (Challis' collection) at the ULC.
T.C. – Trinity College Cambridge, Whewell manuscripts.
RAS Royal Astronomical Society library
R.S. The Royal Society library, Sedgwick letters
O.de P. Observatoire de Paris archive


Airy to Hussey 1834, Nov 23 3pp RGO

Observatory Cambridge

My dear Sir,

I have often thought of the irregularities of Uranus, and since the receipt of your letter have looked more carefully to it. It is a puzzling subject, but I give it as my opinion without hesitation that it is not yet in such a state as to give the smallest hope of making out the nature of any external action on the planet... But if it were certain that there were any extraneous action, I doubt much the probability of determining the place of a planet which produced it. I am sure it could not be done till the nature of the irregularity was well determined from several successive revolutions.

 


Airy to Bouvard R O Greenwich 1837 Oct 12 RGO 4pp

Sir,

I have received your letter of Oct 6, and am glad to find that you propose to yourself to labour on the publication of new tables of Uranus. At the same time I think that probably you would gain very much in the accuracy of the reduced observations by waiting a short time before you proceed with that part of your labour.... I have reduced the observations made at Greenwich in 1836, in the same manner: the volume containing these reductions will very soon by published. You will thus have a year's observations made with the best instruments in existence, far more completely reduced than any others which are published. You may also know that I am engaged upon a general reduction of the observation of planets made at Greenwich from the commencement of Bradley's observation to the present time. It may, perhaps, be years before I can furnish you with the places deduced from these observations: but I am sure that you would find it advantageous to wait for them... the errors of longitude are increasing with fearful rapidity... I cannot conjecture what is the cause of these errors, but I am inclined, in the present instance, to ascribe them to some error in the perturbations... The subject of the correction of the planetary tables is one which I have very much at heart.

 


Challis to Airy RGO

Cambridge Observatory Feb. 16. 1844

My dear Sir,

I am exceedingly obliged by your sending so complete a series of Tabular errors of Uranus. Mr Adams had not dared to ask for more than the errors of ten years. The list you have sent will give him the means of carrying on in the most effective manner the enquiry in which he is engaged.



Airy to Bouvard 2pp RGO

1844 June 27 Royal Obs, Greenwich

Sir,

I shall send to you by post tomorrow two sheets of the printed reductions of the Greenwich Planetary Observations which will probably contain all that you desire relating to Uranus...

 


Challis to Airy 2pp RGO

Cambridge Observatory Sep. 22. 1845

My dear Sir,

My friend, Mr Adams, (who will probably deliver this note to you) has completed his calculations respecting the perturbation of the orbit of Uranus by a supposed ulterior planet, & has arrived at results, which he would be glad to communicate to you personally if you could spare him a few moments of your valuable time. His calculations are formed on the observations you were so good as to furnish him with some time ago, & from his character as a mathematician & his practice in calculation, I should consider the deductions from his premises to be made in a most worthy manner. If he should not have the good fortune to see you at Greenwich he hopes to be allowed to write to you on this subject.

 


Airy to Challis Inst.ofAstron. V, + RGO copy

R.G.Obs 1845 September 29

My Dear Sir,

I was, I suppose, on my way from France when Mr Adams called here. At all events I had not reached home and therefore to my regret I have not seen him. Would you mention to Mr Adams that I am very much interested with the subject of his investigations and that I should be delighted to hear of them by letter from him.

 


Adams to his brother George Cambridge 1845 Feb 26

JCA McA 35:12 not RGONE

My dear George,

I am afraid that I shall come in for the greatest share of the blame due to the neglect of our correspondence as I believe it was my turn to write...

I have examined the instruments we have in our obsery. & find there are some very good ones, but I have not been able to make much use of them yet. The Comet has been easily visible with a common Telescope. I found it myself with O'Bailly's telescope about 3 weeks ago, but lately the weather has not been very favourable & the light of the moon has also contributed to render it less easily seen. It is now receding from the Earth so that there is no chance of its being visible to the naked eye. Thomas wrote a note a few days ago, for the first time this Term, so you see we are all pretty much alike in the epistolatory line. Write again very soon & tell me what you are doing in Euclid & Trigonometry & also in English Composition Etc - I think I must send you a few deductions fm. Euclid to be done & some applications of Trigonometry, to take away some of the dryness of which you complain. Hoping to hear again I remain your affectionate Brother



Adams to brother George St John's College, July 10 1845

McA 35:12

My dear George,

I am afraid you will all think me very negligent for not having written since my return to Cambridge - I found that the greater part of the business of the British Assocn. was already over, but I came in for the latter part of the feast, & had the pleasure of seeing for the first time some of our greatest scientific men, Herschel, Airy, Hamilton, Brewster Etc. wh. was my chief object in returning to Cambridge so soon. I have become a life Member of the Assocn. & hope, if spared, to form a more intimate acquaintance with these eminent men at future meetings of the body. There were many men of Science fm. the Continent who honoured us with their presence &, on the whole, I understand this has been a most satisfactory meeting. I am now working with my pupils as usual, but my labours are much lighter than in term time, having no lectures to give...

 


Eugene Bouvard, "New Tables of Uranus"

(in Comptes Rendus Session Sept 1, 1845, xxi, 524):

The discordances between the observations and the theory induce me to believe that there is much probability in the idea proposed by my uncle, (Alexis Bouvard, whose Tables of Uranus etc. were printed in 1821) as to the existence of another planet, disturbing Uranus.

 


Adams to parents

St John's College McA Box 35:2 23rd Oct 1845

My dear Parents,

I just drop a line to tell you of my safe arrival at Cambridge... Nothing worth mentioning occurred on my journey to London, where I arrived luggage & all very early on Tuesday morning. After waiting till about 2 a.m. [!] for Thomas, I left for Greenwich to call on Mr Airy, who was unfortunately not at home. I left a note for him, however, containing a short statement of the results at which I had arrived, & returned to London, where I found Thomas, who did not come before he had done his day's work.

 


Airy to Adams 1845 November 5 JCA 2:2 2pp RGo copy

Sir,

I am very much obliged by the paper of results which you left here a few days since, showing the perturbations on the place of Uranus produced by a planet with certain assumed elements. - The latter numbers are all extremely interesting: I am not enough acquainted with Flamsteed's observations about 1690 to say whether they have such an error, but I think it extremely probable.

But I should be very glad to know whether the assumed perturbations will explain the error of radius vector of Uranus. This error is now very considerable as you will be able to ascertain by comparing the normal equations, given in the Greenwich Observations each year, for the time before opposition with the times after opposition.

 


Herschel to Adams 1846 Jan 23 JCA 9:15 not RGONE

Dear Sir,

I take the liberty of sending by you a work which if all it contains be correct (and the author ... [about lunar theory and old eclipses] .. If Laplace has really been mistaken a whole year in the Chaldean eclipses - what becomes of the Lunar acceleration! ... you are quite welcome to retain the book.

 


AGM of RAS on 1846 Feb 13 (MNRAS VII pp.65-67)

The gold medal was awarded to Airy for 'his recent publication of the reductions of the Greenwich Planetary Observations from 1750 to 1830. .. it rarely happens that so valuable a present is made by te practical to the theoretical astronomer.

President Captain Smyth said, 'The contents of this precious work are comprised in a quarto volume of above 700 pages ... so may we, perhaps, date a new epoch in planetary astronomy from the appearance of this great work before you, since the desiderata in this department of the sciences are rendered visible, and the necessity for exact instants, a greater refinement of methods, and more delicate observations made apparent.'

 


Airy to William Whewell 1846 June 25 Trin Coll Lib.

The discordance is increasing ... People's notions have long been turned to the effects of an external planet, and upon this there are two remarkabled calculations. One is by Adams of St John's (which in manuscript reached me first). The other is by Le Verrier in the Comptes Rendus of 1 June 1846, which and a previous number I strongly recommend you to consult. both have arrived at the same result, viz. that the present longitude of the said disturber must be somewhere near 325°


Airy to LeVerrier 2pp RGO R O Greenwich 1846 June 26

Sir,

I have read with very great interest the account of your investigations on the probable place of a planet disturbing the motions of Uranus, which is contained in the comptes Rendus de l'Academie of June 1. And I now beg leave to trouble you with the following question: it appears from all the later observations of Uranus made at Greenwich which are not completely reduced in the "Greenwich Observations" of each year, so as to exhibit the effect of an error either in the Tabular Heliocentric longitude (or the Tabular Radius Vector) that the Tabular Radius Vector is consistently too small. And I wish to inquire of you whether this would be a consquence of the disturbance produced by an exterior planet now in the position which you have indicated?

I imagine that it would not be so, because...

 


Airy to Challis RGO

Deanery Ely 1846 July 9 3pp

My dear Sir,

You know that I attach importance to the examination of that part of the heavens in which there is a possible shadow of reason for suspecting the existence of a planet exterior to Uranus. I have thought about the way of making such examination, but I am convinced that (for various reasons of declination, latitude, feebleness of light & regularity of superintendance) there is no prospect whatever of its being made with any chance of success except with the Northumberland Telescope.

Now I should be glad to ask you in the first place whether you could make such an examination?

Presuming that your answer would be in the negative, I would ask Secondly whether supposing that an Assistant were supplied to you for this purpose, you would superintend the examination?

You will readily perceive that all this is in a most unformed state at present, and that I am asking these questions almost at a venture in the hope of rescuing the matter from a state which is, without the assistance that you and your instruments can give, almost desperate.

Therefore I should be glad to have your answer, not only responding simply to my question, but also entering into any other considerations which you think likely to hear on the matter.

 


Airy to Challis 1846 July 13 RGO v. faded

My Dear Sir,

... I only add at present that in my opinion the importance of this inquiry exceeds that of any current work which is of such a nature as not to be totally lost by delay.

 


Challis to Airy, July 18 4pp RGO copy McA 33:1

Cambridge Observatory

(N.B., This letter reads as 1st time Challis had heard of the sky-search proposal - it does not allude to earlier RGO Visitor's meeting)

My dear Sir,

.... I have determined on sweeping for this hypothetical planet...

 


Airy to Challis RO Greenwich 2pp RGO 1846 July 21

My dear Sir,

I am very glad that you seriously think of looking for the possible planet... I believe the Berlin maps may be obtained though Nutt 158 Fleet Street or any German bookseller. There is only one which applies partially to this inquiry.

 


The Times THE NEW PLANET 1846 August 4 not RGONE

... M.Leverrier perceived that there was no chance of attaining a staisfactory solution except by resuming the theory of the new planet in all its elements... It was only after this labour, as repulsive from the length of the calculations as it was difficult from the invention of the methods, that M.Leverrier was able to tell the Academy, "The irregularities of Uranus are due to the action of a planet as yet unknown, which, in January 1, 1847, will pass by the 325th degree of heliocentric longitude."... Let us hope that the stars of which Clairaut speaks [concerning an earlier return of Halley's comet] will not all remain invisible, and that if chance discovered Uranus, we shall soon succeed in seeing the planet whose position has been ascertained by M.Leverrier.

 


Adams to Airy 2nd Sept. 6pp RGO St John's College

Sir,

In the investigation, the results of which I communicated to you last October, the mean distance of the supposed disturbing planet is assumed to be twice that of Uranus. Some assumption is necessary in the first instance, and Bode's law renders it probable that the above distance is not very remote from the truth: but the investigation could scarcely be considereed satisfactory while based on any thing arbitrary; and I therefore determined to repeat the calculation, making a different hypothesis as to the mean distance. The eccentricity also resulting from my former calculations was far to large to be probable; and I found that, although the agreement between theory and observation continued very satisfactory down to 1840, the difference in subsequent years was becoming very sensible, and I hoped that these errors, as well as the eccentricity, might be diminished by taking a different mean distance. Not to make too violent a change, I assumed this distance to be less than the former value by 1/20th part of the whole. The result is very satisfactory, and appears to shew that, by still further diminishing the distance, the agreement between the theory and the earlier observations may be rendered complete, and the eccentricity reduced at the same time to a very small quantity. The mass and the elements of the supposed planet, which result from the two hypotheses, are as follows: -

Hypothesis 1. Hypothesis II.

a/a' = 0.5 a/a' = 0.515

Mean longitude of Planet, 1st Oct. 1846 325° 8' 323° 2'

... By comparing these errors, it may be inferred that the agreement of theory and observation, would be rendered very close by assuming a/a'=0.57, and the corresponding mean longitude on the 1st October, 1846, would be about 315° 20', which I am inclined to think is not far from the truth... I have been thinking of drawing up a brief account of my investigation to present to the British Association..

 


Hind to Challis Sept 16 IoA

3, Allsop's Terrace, New Road, London

Sir,

I have received a letter this morning from M. Faye on the subject of Le Verrier's planet, which I think may be of some service in the search. I mentioned to him a few days since that I had heard you were employed in observing stars with the view to its discovery and that I was similarly occupied. I will give the extract from Mr Faye's letter in his own words: ... Jusqu'ici je ne me suis pas livie a cette recherche, nos instruments ne me paraissant pas assez puissante pour cela.


LeVerrier to Galle 1846 Sept 18 MNRAS, 1911, LXXI, pp278.

A Monsieur J.G.Galle

Vous verrez, Monsieur, que je demonstre qu'on ne peut satisfaire auz observations d'Uranus qu'en introdusiant l'action d'une nouvelle Planete, jusqu'ici inconnu; at ce qui est remarquable, il n'y a dans l'ecliptique qu'une seule position qui puisse etre attribuee a cete Planete perturbatrice. Voici les elements de l'orbite que j'assigne a cet astre.

(Elements, for Jan 1, 1847, True Helio long)

La position actuelle de cet astre montre que nous sommes actuellement, et que nous serons encore, pendant plusieurs mois, dans las conditions favourables pour le d_couvrir.

D'ailleurs, la grandeur de sa masse permet de conclure que la grandeur de son diametre apparent est de plus de 3" sexegesimales.

 


Galle to Leverrier Berlin, le 25. Sept 1846

Monsieur,

La planète dont vous avez signalé la position réelement existe. Le même jour ou j'ai recu votre lettre, je trouvai une etoile de 8me grandeur, qui n'etait pas inscrite dans l'excellente carte Hora XXI (dessine par M. le Dr. Bremmiker) de la Collection de cartes celestes publiee par l'Academie roy. de Berlin.

 

Schumacher to LeVerrier Altona Sept 28

... je ne peux pas resister au penchant de mon coeur, en vous transmettant sans retard mes felicitations les plus sinceres sur votre brilliante decouverte. C'est le plus noble triomphe de la theorie que je connaisse.

 


Hind to Adams Sept 30 JCA 9:23

Understanding from Prof. Challis that you are occupied about the planet of Le Verrier, I think you will be gratified to learn that it was discovered by Dr Galle at Berlin on Sept 23... What a grand discovery this is, and how glorious a triumph for analysis!


LeVerrier to Galle Paris, Octobre 1

...Le Bureau des Longitudes s'est prononcee ici pour Neptune. Le signe un trident.

James Glaisher Blackheath, Oct 1 not RGONE

to The Illustrated London News p.230 Oct 10, The Editor

The circumstance of the discovery of a new Planet at any time cannot fail to be highly interesting, and must necessarily attract much attention. The discovery of a Planet in the space assigned to it by theory must be highly gratifying indeed... Le Verrier was the first to perform these calculations; and on September 23rd, Dr Galle, at Berlin, received a letter from him, requesting a search to be made for the then hypothetical Planet; and, on the same evening, during a comparison of the heavens with Dr Bremicker's map, he saw a star of the eight magnitude not marked on the map, in the constellation of Aquarius, as marked in the annexed Chart.

 


Challis to Cambridge Chronicle Oct 1st

Sir, ... The discovery of this planet is, perhaps, the greatest triumph of astronical science that has ever been recorded. The merit is mainy due to Theoretical Astronomy. About four months ago, Mr Adams, of St. John's college, and M.Le Verrier, an eminent French mathematician, concluded independently from theoretical calculations, that anomalies which had long been known to exist in the motion of the planet Uranus, could be accounted for by supposing a perturbing planet to move in an orbit at twice the distance from the sun. These mathemasticians agreed in fixing on 325° of heliocentric longitude as the most probable positon of the suposed planet, which has proved to be very little different from the actual position. Le Verrier more recently inferred, from a most profound and elaborate investigation, that the mass of the disturbing planet was to that of Uranus in the proportion of 5 to 2, (a result which Mr.Adams also arrived at by continuing his researches), and that it might consequently present a disc discernable in powerful telescopes. He went to far as to recommend seeking to detect it by its physical appearance rather than by the laborious method of mapping stars, and marked out very narrow limits within which the search should be made....

Having been anticipated in the discovery of this planet, I need not detail the efforts I made to find it. I may, however, be permitted to state that for the last two months I have been engaged in mapping the stars in the neighbourhood of the probable place, a method which, though slow, must eventually have been successful. The last investigation of Leverrier came to my knowledge on Sept 29. On the evening of that day I observed strictly according to his suggestions, and out of a vast number of stars which passed through the field of view (power 160), I selected only one, against which I directed my assistant to write, "seems to have a disc." This was the planet. Before I had the opportunity of verifying my suspicion, the news of the discovery reached me.


 

Herschel to The Athenaeum 1846 Oct 1st

p.1019 No. 988 Oct 3rd

In my address to the British Association assembled at Southampton, on the occasion of my resigning the chair to Sir R. Murchison, I stated, among the remarkable astronomical events of the last twelvemonth, that it had added a new planet to our list, - adding, "it has done more, - it has given us the probable prospect of the discovery of another. We see it as Columbus saw America from the shores of Spain. Its movements have been felt, trembling along the far-reaching line of our analysis, with a certainty hardly inferior to occular demonstration." - These expressions are not reported in any of the papers which profess to give an account of the proceedings, but I appeal to all present whether they were not used.

The remarkable calculations of M.Leverrier - which have pointed out, as now appears, nearly the true situation of the new planet, by resolving the inverse problem of perturbations - if uncorroborated by repetition of the numerical calculations by another hand, or by independent investigation from another quarter, would hardly justify so strong an assurance as that conveyed by my exprtessions above alluded to. But it was known to me, at that time, (I will take the liberty to cite the Astronomer-Royal as my authority) that a similar investigation had been independently entered into, and a conclusion as to the situation of the new planet very nearly coincident with M.Le Verrier's arrived at (in entire ignorance of his conclusions), by a young Cambridge mathematician, Mr Adams;- who will, I hope, pardon this mention of his name (the matter being one of great historical moment), - and who will, doubtless, in his own good time and manner, place his calculations before the public.

 


Challis to Arago, Cambridge Oct 5

(this letter only exists in French translation, Comptes Rendus 12th October 1846 p.715)

Je n'avais pas encore pousse le travail jusqu'a la position actuelle de la planete, lorsque j'eus connaissance, le 29 septembre, par le no 662 du journal l'Institut, des resultats des dernieres recherches de M. Le Verrier. Je ,me conformai strictemet aux suggestions de cet astronome, at je me renfermai dans les limites qu'il avait indiquees.

 


John Stevelly to Herschel Belfast

8th October 1846

I have read with much interest your letter to The Athenaeum, and feel I think as warmly as I should on the announcement of the discovery of the new Planet which succeeded it. In my opinion your simple averment that you had used at Southampton the very remarkable words which you quote would have been quite sufficient to satisfy any person interested in these matters that you had used them; but as you have deemed it proper to appeal to those present on the occasion, I have no hesitation in saying that I remember the words most distinctly. I am much surprised that they were not reported for they fastened themselves more upon my imagination, and afforded me more matter for mental speculation then almost any other sentence you had uttered: but I was totally ignorant of the history which has now come out. I supposed that analysis was leading to the conviction that another asteroid of the Astraea class must exist and might soon be discovered.

 


Challis to Airy

Cambridge Observatory Oct. 12. 1846

My dear Sir,

.. I commenced observing on July 29, attacking first of all, as it was prudent to do, the position which Mr Adams' calculations assigned as the most probable place of the planet. .. In this way I took all the stars to the 11th magnitude in a zone 9' in breadth... The space gone over on August 12 exceeded in length that of July 30, but included the whole of it. on comparing the observations of these two days, I found that the zone of July 30 contained every star in the corresponding position of the zone of Aug.12, except one star of the 8th magnitude. This, according to the principle of search, which in the want of a good star-map I had adopted, must have been a Planet. It had wandered into the latter zone in the interval between July 30 & Aug. 12. By this statement you will see that after four days of observing the Planet was in my grasp if only I had examined or mapped the observations. I delayed doing this partly because I thought the probability of discovery was very small till a much larger portion of the heavens were scrutinised...

 


Airy to Herschel McA 33:2 RGO 7/247 f16-17

Royal Observatory, Greenwich 1846 Oct 13

My dear Sir,

...Before leaving Germany, I had pretty well determined to write an account of the English transactions relating to this planet (always supposing that Mr Adams and Professor Challis do not object to my publishing their letters) and to present it to the R. Astronomical Society. First, it ought to be done, because it will be an interesting history and well illustrative of the present state of science. Secondly, I can do it better than anybody else, because my position enabled me to know generally some points of the progress in both the theoretical and the observing directions, while I myself did nothing at all in either.

 


Airy to Adams 1846 Oct 14 JCA 2:2

Dear Sir

In reference to this, it appears to me proper that I should write a commentary to the R.Astronomical Society an account of what I know of the English transaction thereto relating. My reasons as I have already explained to Professor Challis, are - 1st. That it is illustrative of the history of science, 2nd. That it would do justice to England. - 3rd that it would do justice to individuals - 4th. I could do it because I know nearly all the history and yet have taken no part in the theory or the observation.

 


Airy to LeVerrier McA 33:3

Royal Observatory, Greenwich, 1846. Oct 14.

May you enjoy the honours which await you! and may you undertake other works with the same skill and the same success, and receive from all, the enjoyment which you merit!

I do not know whether you are aware that collateral researches had been going on in England, and that they had led to precisely the same result as yours. I think it probable that I shall be called upon to give an account of these. If in this I shall give praise to others I beg that you will not consider it as at all interfering with my acknowledgement of your claims. You are to be recognised, beyond doubt, as the real predictor of the planet's place. I may add that the english investigations, as I believe, were not quite so extensive as yours. They were known to me earlier than yours.

There is one thing which somewhat disturbs my mythological ideas, namely the name Neptune, which (it is understood) you propose to fix upon the planet. There seems to be an interruption of order which is unpleasant. If you would consent to adopt the name Oceanus instead, it would, I think, be better received, as more similar in its character to that of its predecessor, Uranus, and more closely related to the mythological ideas of the Greeks.

 


The Guardian (London) Oct 14 LE VERRIER'S PLANET No.25, p.389

The last month has witnessed one of the most remarkable triumphs of modern science ... The credit of this brilliant discovery belongs to a French Astronomer, M. LE VERRIER, and we earnestly hope that no attempt will be made to diminish his well-won honour ... it was reserved for M. LE VERRIER to venture to make an unknown planet the subject of a rigorous mathematical problem, and on mathematical grounds alone, and with mathematical exactness, to anticipate and guide the observer. Calculations of the same nature may have been engaging the simultaneous attention of other mathematicians,* but M.LE VERRIER's claim to the honour of this achievement must always be paramount, because he first had such confidence in his theory, as to announce it publicly, without qualification, and in the minutest expression, and to stake his credit on its verification.

..................................

* Sir J.Herschel's Letter to the Athenaeum, given in the Guardian of last week.

 


Adams to Airy McA 33:3

Cambridge Oct 15th 1846

...Professor Challis has, I believe, communicated to you the remarkable fact that he observed the planet so long ago as August 4th, and again on August 12th, the first date being only a few days after he commenced the search for it. I have been founding some calculations on the comparison of these with the recent observations & although the interval is far too small for the determination of elliptic elements, I have ascertained that the distance of the planet from the Sun at present is not far from 30.05 which is considerably less than the value given by M. le Verrier. In my letter of Septr. 2nd I inferred that the mean distance used in my first hypothesis must be greatly diminished, but I rather hastily concluded that the change in the mean Long. deduced would be nearly proportional to the change in the assumed mean distance.

 


Challis to Athenaeum Cambridge Oct 15th

No 990 p.1069, Oct 17

The allusion made by Sir John Herschel in his letter contained in the Athenaeum of October 3rd, to the theoretical researches of Mr Adams, respecting the newly-discovered planet, has induced me to request that you would make the following communication public. ... In September, 1845, Mr Adams communicated to me values which he had obtained for the heliocentric longitude, excentricity of orbit, longitude of perihelion, and mass, of an assumed exterior planet, - deduced entirely from unaccounted-for perturbations of Uranus. The same results, somewhat corrected, he communicated, in October, to the Astronomer-Royal. M.Le Verrier, in an investigation which was published in June of 1846, assigned very nearly the same heliocentric longitude for the probable position of the planet as Mr Adams had arrived at, but gave no results respecting its mass and the form of its orbit... I undertook to make the search,- and commenced observing on July 29. The observations were directed, in the first instance, to the part of the heavens which theory had pointed out as the most probable place opf the planet; in selecting which I was guided by a paper drawn up for me by Mr. Adams. Not having hour XXI of the Berlin star-maps - of the publication of which I weas not aware - I had to proceed on the principle of comparison of observations made at intervals. On July 30, I went over a zone 9' broad, in such a manner as to include all stars of the eleventh magnitude. On August 4, I took a broader zone,- and recorded a place of the planet. My next observations were on August 12; when I met with a star of the eighth magnitude in the zone which I had gone over on July 30,- and which did not then contain this star. Of course, this was the planet;- the place of which was, thus, recorded a second time in four days of observing. A comparison of the observations of July 30 and August 12 would, according to the principle of search which I employed, have shown me the planet. I did not make the comparison till after the detection of it at Berlin - partly because I had an impression that a much more extensive search was required to give any probability of discovery- and partly from the press of other occupation. The planet, however, was secured, and two positions of it recorded six weeks earlier here than in any other observatory, - and in a systematic search expressly undertaken for the purpose. I give now the positions of the planet on august 4 and August 12.

(R.A., N.P.D. positions)

From these places compared with recent observations Mr Adams has obtained the following results:-

Distance of the planet from the sun... 30.05

Inclination of the orbit ........ 1° 45'

Longitude of the descending node .....309° 43'

Geocentric longitude, Aug 4. ..... 326° 39'

The present distance from the sun is, therefore, thirty times the earth's mean distance;- which is somewhat less than the theory had indicated. The other elements of the orbit cannot be approximated to till the observations shall have been continued for a longer period.

The part taken by Mr. Adams in the theoretical search after this planet will, perhaps, be considered to justify the suggesting of a name. With his consent, I mention Oceanus as one which may possibly receive the votes of astronomers.- I have authority to state that Mr Adams's investigations will, in a short time, be published in detail.

McA 33:4


Leverrier to Airy 4pp RGO Paris, le 16 Octobre 1846

Monsieur et illustre Confrere,

Pourquoi Mr Adams aurait-il garde le silence depuis quatre mois? Pourquoi n'aurait-il pas parle des les mois de Juin, s'il eut eu de bones raisons a donner? Poirquoi attend-on que l'astre ait ete vu dans les lunettes?

Translation: Why would Mr Adams have kept silent for four months? Why would he not have spoken from the month of June (onwards) if he had had good reasons to give? Why wait until the object has been seen in the telescope?... Is it enough to have undertaken researches on a subject in order to claim to share the result? In that case Mr Adams and I will find many competitors in France who will take precedence by much in date.

 


Challis to Cambridge Chronicle Oct 16

Sir - As the discovery of a new planet is justly regarded as a matter of great scientific interest, I am desirous of correcting an inaccurate statement contained in my letter on the subject in the chronicle of October 3. Writing in haste, without consulting memoranda, and not having an oportunity of communicating with Mr Adams, I said incorrectly that Mr Adams and M.Le Verrier, about four months ago, determined theoretically the probable heliocentric longitude of the planet. The fact is, that in September last year Mr Adams communicated to me, and in the following month to the Astronomer Royal, values which he had obtained not only of the heliocentric longitude, but also of the mass, longiude of perihelion, and eccentricity of the orbit of the supposed planet.

 


Airy to LeVerrier 4pp. McA 33:5

Royal Observatory, Greenwich 1846 October 19

Dear Sir,

A considerable time ago, probably in the year 1844 or in the beginning of 1845 {I have not had leisure since my return to refer to my papers} I supplied Mr Adams with several places of Uranus, expressly for an investigation into the cause of its disturbance. In October or November 1845 I received from Mr Adams a notification that the disturbances could be explained by supposing another planet to exist, of which he gave me the elements.

Shortly after this I addressed to him the same inquiry which I afterwards addressed to you, namely whether the error of radius vector was explained by the same disturbing planet. I know not whether any accident prevented Mr Adams from receiving my letter: at any rate, he gave me no answer. Had he answered me, I should have urged him immediately to publish his investigations.

In June 1846 the numero of the Comptes Rendus containing your investigations was received by me: I was astonished and delighted to find that the elements were nearly the same and the present apparent place of the disturbing planet nearly the same as those given by Mr Adams' investigations.

On June 29th a meeting of the Board of Visitors of the Royal Observatory was held at which Sir J.Herschel and Professor Challis were present. At this meeting there was question about the expediency of distributing subjects of observations among the different observatories, and I strongly urged the importance of such distribution in some cases, and I specially stated the probability of now finding the disturbing planet if one observatory could be devoted to the search for it. I gave as my reason the very strong evidence afforded by the agreement of the result of your researches and Mr Adams' researches. It was my strong statement upon this that induced Sir John Herschel so to express himself at the meeting of the British Association and to write such a letter to the Athenaeum. It was my statement also which (followed by some correspondence) induced Professor Challis to search for the planet. Professor Challis commenced his search on July 29th, and saw the planet first on August 4, and subsequently on August 12. All the rest of the history is known to you. I am confident that you will now see that sir John Herschel was justified in every expression which he has used.

But, my dear Sir, you express yourself surprised that any one should suppose that the results of mathematical investigations required confirmation. If any person had reason to complain of this, it would be Mr Adams: for we waited until Mr Adams' results were confirmed by yours, and not until yours were confirmed by Mr Adams.

 


LeVerrier to Airy, 2pp RGO McA 33:5

Paris, le 19 Octobre 1846

Monsieur et illustre confere,

Vous aurez sans-doute ete surpris de m'entendre declarer que j'avais entre les mains une lettre de Mr Challis, etablissant que cet astronome avait cherche la planete d'apres mon travail. Comment le concilier avec la lettre qu'il a publiee dans l'Athenaeum?

... Il m'etait impossible de deviner que pendant que Mr Challis disait blanc en France, il disait noir en angleterre.

 


Royal Observatory, Greenwich 1846 October 21

Airy to LeVerrier McA 33:6

Of one thing, however, I am sure you may make yourself quite certain, - that no person in England will dispute the completeness of your investigations, the sagacity of your remarks on the points it was important to observe, and the firmness of your moral convictions as to the accuracy and certainty of the results. With these things, the product not only of a mathematical but also of a philosophical mind, we have nothing which we can put in competition. My acknowledgement of this will never be wanting; nor, I am confident, will that of any other Englishman who really knows the history of the matter.

 

LE NATIONAL of 21 October

ACADEMIE DES SCIENCES

Seance du 19 octobre

LE VOL A LA PLANETE

...Le fait est que les trois premiers astronomes de la Grand-Bretagne ont organise a loisir un miserable com-plot pour voler la decouverte do M. LeVerrier. Ce sont M.John Herschel (le fils de celui dont M. Arago a fait connaitre la gloire a toute l'Europe), M. Airy, directeur de l'observatoire de greenwich, at M.Challis, directeur de l'Observatoire de Cambridge qui ... ont fait le coup! (It cites 3 dates, June 1st & Aug 31 of Lev's papers, then Sept 23rd the discovery, then continues:)

A cette epoque, que faisait les astronomes anglais? Aucune publication officielle, aucune confidence aux journaux, aucun de ces bruits qui accompagnent les recherches scientifiques n'avaient permis de soupconner qu'on s'occupait du meme sujet en Angleterre. Bien mieux, M.Airy, de Greenwich, et M.Challis, de Cambridge (deux de nos trois culpables) annoncaient positivement dans les lettres suivantes qu'ils n'auraient jamais rien a revendiquer dans la decouverte de notre compatriote.

Voici ce qu'ecriverait M.Airy a M.Leverrier, le 26 Juin (reproduces Airy's letter to LeVerrier of June 26)

Ainsi, le 26 Juin 1846, non-seulement M.Airy ne possedait pas des calculs anglais semblables de M.Leverrier, mais il relevait dans les calculs de notre compatriote des circonstances incompatibles avec la position assignee a sa planete encore hypothetique: "Le desordre observe dans la marche d'Uranus, dit-il expressement, est-il produit par une planete situee a la place ou vous la-mettez? JE NE CROIS PAS QU'IL EN SOIT AINSI" Et il montre pourquoi....

[NB, this isn't an entirely fair comment upon Airy's letter, which was inquiring upon the radius vector, N.K.]

Arago to Airy Oct 23 McA 33:6

Conseil General Municipal, Dept de la Siene, Ville de Paris

Mon cher et illustre confere,

L'academie s'est occupee, lundi dernier, de la reclamation de priorite que vous, Mr Herschel et Mr Challis avez cru devoir soulever en faveur de Mr Adams.

J'ai porte la parole dans ce debat. En combattant des idees que je ne crois point justes, je n'ai pas oublie qu'elles etaient presentees et apuyees par des hommes d'un grand talent et du plus noble charactere. Un journaliste a rendu compte de notre seance, en des termes qui ont excite ma plu vive indignation. Ce sentiment a ete partage par touts les amis eclaires des sciences. J'avais besoin de vous en donner l'assurance.

 


Airy to Arago McA 33:7

Royal Observatory, Greenwich 1846 October, 26

My Dear Sir,

With very great pleasure I yesterday received your letter of the 23rd, disclaiming the articles relating to the New Planet in The National of Oct 21. It was impossible for any one, who is personally acquainted with yourself or with other men of science in France, to suppose that the discreditable article, to which I allude, could have your sanction: but I am very glad that you have put it in my power formally to announce this to the British public. I, and every other Englishman, recognise fully the right of French savans to urge or to support the claims of French discoverors, and we are quite certain that these claims will be asserted, within the French academy, in a dignified and courteous tone. In like manner we claim for ourselves the right of explaining what our countrymen and friends have done, conceiving it also to be our duty to express ourselves in courteous language. I am proud to say that no paper published in England, which I have yet seen, has transgressed this rule. I write to M Le Verrier to-day, and (as I gather from M. Le Verrier's letters that you are entirely in his confidence) I will state to you two points which I have urged on him.

The first is - that I have not published a word of any kind or in any manner relating to the New Planet; and that I have not written a word to any person in France excep to M.Le Verrier himself: and that my letters to him were intended to be most friendly. Under these circumstances, it is a matter of great surprise to me that these letters should be produced in public in such a way that I should become the subject of public abuse in France. It appears that copies of my letters have been supplied in some manner to the National newspaper. This transaction is entirely opposed to our English ideas of propriety: I cannot conceive it to be quite right. There is one thing which M. Le Verrier, as a man of honour, is now bound to do. In my letters of October 19 and October 21 I have given, I believe, the whole history of the English part of this affair: and, I think, in such a manner as to remove much of the misunderstanding which has prevailed. I think that M.Le Verrier is bound to place these letters in your hands.

The second is that M.Le Verrier is under some total misapprehension as to the conduct of Professor Challis. There is not in the whole world a man more scrupulously just than Professor Challis. You will learn from my letters (to which I have alluded) what was his course of observation. At my instigation, which was founded upon the confirmation of Mr Adams' results (long before known to us) by M.Le Verrier's results. Professor Challis began observations in July, referring generally to Mr Adams for the planet's place, but sweeping a very large zone.

On Sept. 29 he received M. Le Verrier's second paper, and was so much struck with the sagacity of the considerations and the force with which they were presented that he immediately restricted his observations to a much smaller zone. In this there is none of the inconsistence (sic) which M.Le Verrier in his letters, and the National in its scurrilous article ascribe to Professor Challis. And there is no inconsistence in his two statements of them.

 

<hr>Airy to The Athenaeum R O Greenwich Oct 26

p.118, No. 992, Oct 31

In the National French newspaper of the 21st instant there is a most virulent article on the subject of the New Planet; containing a report of the meeting of the French Academy on the 19th (in which the priority of predictions of the planet was discussed), and loading Sir John Herschel, Professor Challis, and myself with grossest abuse...

 


Herschel to The Guardian (London) Collingwood Oct 28 1846

No. 27, p.421

Sir, - I deeply regret that Mr Le Verrier should have found cause of complaint or offence in my communication to the Athenaeum. nothing was ever further from my intention than to detract from the glory of his noble discovery, or tear one leaf from the wreath which he has so honourably won. The prize is his by all the rules of fair adjudication, and there is not a man in England who will grudge him its possession.

I do not wish here to repeat the offence of which M LeVerrier conceives I have been guilty, but I must say a few words in explanation of my motives. The history of this grand discovery is that of thought in one of its highest manifestations, of science in one of its most refined applications. So viewed, it offers a deeper interest than any personal question. In proportion to the importance of this step, it is surely interesting to know that more than one mathematician has been found capable of taking it. The fact, thus stated, becomes, so to speak, a measure of the maturity of our science; nor can I conceive anything better calculated to impress the general mind with a respect for the mass of accumulated facts, laws, and methods, as they exist at present, and the reality and efficiency of the forms into which they have been moulded, than such a circumstance. We need some reminder of this kind in England, where a want of faith in the higher theories is still to a certain degree our besetting weakness.

 


Schumacher to Airy (trans, copied excerpt?) Date?

I scarcely know what I shall say about Mr Challis. He sees the great probability that the predicted planet must exist by the near coincidence of its place, which two, totally indepencent Calculators assign. You request sweeps with the Northumberland Equatorial from him. He makes such sweeps July 30, Aug. 4, and Aug 12, but lays them aside, without looking at them. Now such observations are only made in order to compare them one with the other, and to see if a star has changed its relative place to the others. First when he hears that the new planet has been observed Sep 23 at Berlin, he examines his observations made nearly two months before...

 


Augustus de Morgan Editorial in The Athenaeum not RGONE

1846 Oct 31 p.1117, No 992

THE NEW PLANET AND THE FRENCH ASTRONOMERS

Our neighbours, the French - or at least some of the journalists and some of the members of the Institute - are in a great state of excitement about what they consider as the attempt to deprive their countryman, Leverrier, of the honour of his new planet. They may rest easy;- no power on earth can deprive him of an immortal name amongst astronomers...

The facts at this moment are simple;- and out of their simplicity arises what may be, or may not, be a difficult issue to try. M.Leverrier has calculated - has predicted- and has had his prediction verified. He has also been the first to make a perfect public announcement, complete in itself. But Mr Adams also calculated; and furnished Mr Challis with the means of actually securing two observations of the planet previous to any such announcement by M. Leverrier...

Mr Adams' claim, whatever it might be, should not be lost by an early statement of the facts upon proof of which it is to rest.

 


Challis to Airy McA 33:8

Nov 3 1846

Cambridge Observatory

Nov 3 1846

Wartmann's star, which they have been talking about in the French Academy, Adams considered long since, and ascertained that if the observations are at all approximate, it must be much nearer the Sun than the new Planet.

I am sorry to say I can give no hopes of Adams's being able to undertake the Astronomical Report. He is moderator this year, and this, with his college duties, takes his time. I am in difficulty about this Report, & should be glad to see some means of getting out of it.

 


From Herschel to W.Whewell Nov 6 1846 RS HS 22:256

I mourn over the loss to England and to Cambridge of a discovery which ought to have been theirs every inch of it, but I have said enough about it to get heartily abused in France, and I don't want to get hated in England for saying more.

 


J.R.Hind to Rev. R. Sheepshanks RAS McA 34:15 1846 Nov 12

Dear Sir,

I am quite willing to allow Mr Adams all the merit he deserves for the investigations made by him, but I cannot admit that he is entitled to any share whatever in the discovery itself. Nor do I see how Mr Challis can lay claim to any credit in the discovery as it is very evident he did not place much dependence on his obsns. or he should have found the planet in August last. It is very well for the Cambridge people to do the best for their own men. I am sure you must have noticed the inexcusable secrecy observed by all those acquainted with Mr Adams results: it is this secrecy which I hold to deprive Mr A. of all share in the discovery and I am very glad to find, that I am not the only one who thinks so. Moreover it appears to me very intrusive in the Cambridge people to urge a name for the planet on Astronomers, and one too which is no more likely to succeed with the French (who have the only right to name it) than if it had been dubbed "Wellington"

 


Adams to Airy, McA 33:8 St John's Coll.

18th Nov. 1846

…. For several years past, the observed place of Uranus has been falling rapidly more and more behind its Tabular place. In other words, the real angular motion of Uranus is considerably slower than that given by the Tables. This appeared to me to show clearly that the Tabular Radius Vector would be considerably increased by any theory which represented the motion in Longitude, for the variation in the second member of the eqn.

r2.dΘ/dt = Ö (μα(1-e2) is very small.

Accordingly, I found that if I simply corrected the elliptic elements, so as to satisfy the modern observations as nearly as possible, without taking into account any additional perturbations, the corresponding increase in the Radius Vector would not be very different from that given by my actual Theory. Hence it was that I was led to defer writing to you till I could find time to draw up an account of the method employed to obtain the results which I had communicated to you.

P.S. - I drew up a paper for the meeting of the British Association at Southampton, but did not arrive there in sufficient time to present it, as section A closed its sittings one day earlier than I expected.


Sheepshanks to Challis Nov 20 Reading IoA not RGONE

I have been struck with the sort of fatality, which has burned us to the very heart [pursued us the very heart ??]. The most prudent precautions & best schemed places of observation have failed from causes which no-one could forsee and which few will now allow for.

 


Adams to Whewell JCA 38:20 not RGONE

St John's College 24th nov. 1846

Dear Sir,

It is quite true that I conceived the idea of trying to account for the anomalies in the motion of Uranus by the action of another planet in 1841. My attention was directed to the subject by reading Mr Airy's valuable Report on the Recent progress of Astronomy, in which the fact of the existence of these anomalies is put prominently forward. On considering the subject, it appeared to me that by far the most probable hypothesis that could be formed to account for these irregularities was that of the existence of an exterior undiscovered planet. None of the other hypotheses that had been thrown out, appeared to possess the slightest claims of attention, being very improbable in themselves & incapable of being tested to any great calculation.

The first mentioned hypothesis on the contrary, appeared to be thoroughly in accordance with the present state of our knowledge & promised to lead to an approximate determination of the position of the disturbing body. The following is a copy of a memorandum on this subject preserved among my papers, which may be interesting to you.

"1841 July 3. formed a design in the beginning of this work of investigating as soon as possible after taking my degree, the irregularities in the motion of Uranus which are yet unaccounted for, in order to find whether they may be attributed to the action of an undiscovered planet beyond it; & if possible, thence to determine approximately the elements of its orbit Etc. which would probably lead to its discovery."

Accordingly in 1843 I commenced my calculations & in the course of that year, I arrived at a first solution of that problem, which, though incomplete in itself, fully convinced me that the hypothesis which I had formed was quite adequate to account for the observed irregularities, & that the place of the disturbing body might be very approximately determined by a more extended investigation.

 


RS:HS14.364 Translation Arago to Herschel

Paris 22nd November 1846

My dear colleague and friend

I was eager to show the letter you sent me, which was so loyal and so agreeable, to Mr LeVerrier. He was charmed by it. Your feelings towards him gave birth to a thought which I hope you will welcome with kindness: my young friend will beg you to represent him on the day when the Royal Society awards him the Copley Medal. The misunderstanding of a few weeks ago could not be resolved more happily.

I can see the time when I reprint my analysis of the works of your illustrious father, rapidly approaching. Have the goodness to point out the errors that I may have committed so that I can correct them. I would also like to know if there is a portrait of your father in existence, in which the resemblance is incontestable. I would have it reduced by one of our best artists and I would place it at the head of my account, to the great satisfaction of the French Public.

PS I hope that you will find nothing amiss with the way in which I spoke of you in the last but one report of the Academy of Sciences.

 


RS:HS11.195 Translation

Leverrier to Herschel Paris 22nd March 1846

Sir and Eminent colleague

Mr Arago has shown me the letter which you wrote to him recently and in which you announced that the Royal Society had awarded me the Copley Medal.

I am particularly happy that this decision was taken at your request and to bear witness to the value that I attach to such an honourable step for me, I ask your leave to make a fitting response to your compliment by begging you to be my representative and to express my gratitude at the meeting which will be so glorious for me, on the 30th November.

Please accept Sir and eminent colleague, my deep and respectful homage.

U J Leverrier

 

 


To Mr Herschel

 

Sedgwick to Airy McA 33:9

Cambridge Dec 3 1846

My dear Airy,

I write in a great hurry (almost on my way to my lecture room) in consequence of a conversation at Pembroke lodge reported to me in our Combination Room yesterday evening. I was too stupid & sleepy to write last night. You were accused not only of unreasonable incredulity & apathy towards Adams of St John, but also of having (as was said) "snubbed him from the first," & so acting on a timid person, prevented him from reaping the honours of a great discovery. This kind of charge I heard before, repeated in public by two M.A's of St Johns about three weeks since, when you & Challis were both blamed, but you more than Challis. The most specific charge in proof of what was called "snubbing" was this, viz., that Adams communicated certain important results when you were away - so far of course no blame in the case - but after your return, that Adams called again, when you were at home; & that you refused to give him an audience. This is to me quite incredible, & I hope you will enable me to meet it by a point blank contradiction. Pray do so by return of post if you can, I have no doubt some fact is here either invented or distorted. -

As to apathy & incredulity misapplied I think the facts speak so loudly that my dull ears cannot help hearing them. Your own statement is clearly & honestly written & certainly is not written in the spirit of self-praise. Had the results communicated to you & Challis been sent to Berlin, I am told, they came so near the mark, that to a certainty the new planet would have been made out in a very few weeks, perhaps a very few days, & the whole business settled in 1845 - Adams the sole, unadvised, unassisted, discoveror. Is this so? Do Adams' results come so near the mark as to justify such language? If so, I must myself chime in with the pack of grumblers. To say the very least of it, a grand occasion has been thrown away. The timidity of Adams was truly astonishing.

I think I know you too well, & I value your friendship too much to think you will be angry with me for writing as I am doing. - But stop a moment! There is one point more I had forgotten - When about June last Le Verrier published one of the results Adams had obtained before (Septr. 1845) Why, in the name of wonder, was not all Europe made to ring with the fact thast a B.A. of Cambridge had done all this (& more than this) ten months previously? Now was, surely, the time to secure priority.


Airy to Sedgwick McA 34:17

R O Greenwich 1846 Dec 4

Dear Sedgwick,

I will answer your letter as explicitly as I can in the short time I have to spare.

Charge 1. - Of "(some word that I cannot read)" and "apathy" towards Adams, & of having "snubbed" him.

As touching apathy, look at my letter of Nov 5, 1845, and see whether it looks like apathy.

as touching snubbing, I never had any opportunity of doing so. My whole epistolatory communication with Adams is printed in the "Account"; & I never saw him but twice, once somewhere with Challis (I totally forget where), and once when Hansen and I came for half a day to Cambridge & we were walking over St. John's bridge. The interview on each occasion might last 2 minutes. No other opportunity of seeing him.

...Charge 2. "That Adams called when I was at home, and that I refused to give him an audience".

Untrue.

Charge 4. "Adams is a very young man - & he had no backer to urge him on, & he says I did my best in sending my results to two national observatories".

I am quite certain that no person can read my letter of November 5 1845 without seeing that I took very great interest in what Adams was about, & that I entered so far into it as to ask for fuller & more critical information. Adams, by not answering my letter, not only left the matter in an unsatisfactory state, and thereby "did not do his best in about sending results", but also entirely stopped me from writing again.

Charge 5. "When about June last Le Verrier published one of the results Adams had obtained before (Sept. 1845), why, in the name of wonder, was not all Europe made to ring with the fact that a B.A. of Cambridge had done this ten months previously?"

In the name of wonder what had I to do with this publication? No understood rule of society would have justified me in doing so. The first person to publish was Adams. The second was Challis. The third was I. But there was a very serious difficulty in the way of my doing so, because Adams had declined to answer my letter. Moreover, in consequence of my question not having been resolved, I had not till I received Le verrier's explanatory letter the security for the truth of the theory which I desired.

I shall wipe my bloody nose quietly at home.

Yours most truly,

G.B.Airy

 


Capt W.W. Smyth to G.B.Airy 5 December 1846

I don't quite like this proposed change in the nomenclature of the Planets, for mythology is neutral ground. Herschel is a good name enough. Le Verrier somehow or other suggests the idea of a Fabriquant & is therefore not so good. But just think how awkward it would be if the next planet should be discovered by a German: by a Bugge, a Funk, or your hirsuite friend Boguslawski!

 


Augustus de Morgan Editorial, The Athenaeum 1846 Dec 5th

p.1245-6,6

…It was a mere question of luck at the last; and if the Cambridge library had possessed the twenty-first hour of the Berlin star-maps, Adams and LeVerrier would have changed places....

We have just seen the Comptes Rendus of the 5th and 19th of October. In the first, M. Arago pledges himself, whatever may happen, not to call the new body by and name except the planet Leverrier. In the second, without waiting for Mr Airy's explanation, he decides that Mr Adams is not entitled to the slightest allusion in the history of the discovery... [Arago's] distorting mirror of national bias .. his mania...

 


Sedgwick to Mrs Airy McA 33:10

Sunday Evening, Dec 6. 1846

My dear Mrs Airy,

Many thanks for your kind letter...Adams, tho' a great philosopher in his way, has shown no worldly wisdom - indeed has acted like a bashful boy rather than like a man who has made a great discovery -

The main facts (as stated by Adams) are as follows (1) He called at the Observatory soon after his calculations were finished - the Astronomer Royal away - Bad luck but no blame anywhere - this was sept 1835 [sic] - (2) called again (Octr. the same Autumn) & the Astronomer out - Left his card - heard that Airy would return soon, & therefore left word that he would call again - (3) Did call again (I think in a little more than an hour) & was told that the Astronomer was at dinner; had no message; & therefore went away. But he added that he did not call by appointment - He only took his chance on his way back from Devonshire to Cambridge, etc. etc. - I collected that he had been mortified (I am not using his own words) at receiving no message on the second call in October.

"I thought," (said he) "that though he had been at dinner he would have sent me a message, or perhaps spoken a word or two to me: but I am now convinced that in fact he never knew of my second call" - that the servant had not delivered my message with my card." - ... But he added "I did think that the Astronomer Royal would have communicated my results among his correspondents - I took all that for granted, & I thought it a publication" etc. etc


Airy’s Dec 8th letter to Sedgwick: see section, ‘Airy blows his top’

W.Airy to Airy

Keysoe. 9 Dec. 1846

Dear George,

When I was at Cambridge last week I heard so much about the new planet that I actually went to bed and dreamed about it. You are aware, I know, that the Johnians have taken up the cudgels against you for 'snubbing' Adams, but I think whern Sedgwick wrote to you (unless he has written a second time) he had not heard the specific charge viz, "that you had appointed to see Adams some day before 2 o'clock; and when he called at 1/2 past one you were denied to him."

 


Segdwick to Airy McA 33:10

Cambridge Wednesday Dec 9. 1846

In regard to the latter & ludicrous statement of your letter. I must allow that Adams has shown little worldly wisdom, and acted like a very simpleton - I never spoke to him till lately, after this discussion was on the table [sic], & I ran some risk of offending him by more than one thing I said to him.... Don't blame Adams, & and above all don't blame me, for rash & foolish words spoken by others. I love you & your family so much, & so highly respect & honour you, that I should think it the greatest misfortune of my life were you to entertain a single unkind thought respecting me -


Airy to Sedgwick McA 34:17

Flamsteed House - Greenwich 1846 Dec 10

Dear Sedgwick,

I shall disobey the first command of your letter, because I am fully as anxious to stand right with you as you with me. Now first "I doubt not the facts of Adams' call were as you & Adams have made out". You will observe that I made out I do not mean concocted, but I do mean ascertained by investigation, with the assistance of rational conjecture to fill up gaps.... I blame and blame severely those who have driven you into such a corner. They have by their low conduct produced such a train of circumstances that you have been compelled to ask questions which no gentleman if free would ask and which no gentleman could be expected to answer. Receive my assurances that I am and was perfectly satisfied with what you have done - and that quite independently of the result to which it has led: But never let me see the low fellows who have caused it.


 

The Liverpool and Lancashire General Advertiser (weekly)

Friday Dec 11 1846

Astronomy, the New Planet by John Taylor

...M.Le Verrier is the man who has done the work, and to him the honour is due.

LE VERRIER first his learned eye upraised,

And on the problem with fixed purpose gazed:

No inward fears subdued his generous soul;

No dread of censure could his mind control;

The fame of others his bold spirit fired,

And with the hope to emulate inspired.

He passed the barriers of those distant bounds,

Once thought to mark the planet's lonely rounds,

Tracing each wanderer in its varying course,

To each assigning its attractive force;

Planting the flag of Science wide unfurled

Upon the flaming ramparts of the world;

And traversing the Spheres by mental toil,

returns victorious with his well-earned toil.

The laborious calculations made by LeVerrier on the secular inequalities of the elements of the orbits, of the seven principal planets before known, had prepared him for the task of ascertaining whether there really were an unknown planet revolving in the orbit laid down for it, in suppostion, by Bode and De Lambre: in fact, it was only an extension of his preceding work, a corollary easy to be deduced from it. The attempt by Mr Adams was merely a rude sketch, which he was prevented from perfecting by the attempt to determine the latitude as well as the longitude of the body sought for. In trying to find out the inclination of the plane of the planet's orbit; he wandered from the object directly before him; and the calculations probably got entangled in nodes which Mr Adams could not untie. M. Le Verrier, from the remoteness of the planet, concluded that the plane of its orbit would so nearly coincide with that of Uranus as to allow of its being assumed to be the same. He thus, like another Alexander, cut rhe Gordian knot: this saved time and gave him the victory. In the elements for the new planet, given by Le Verrier, there is no notice of the inclination of its orbit, nor of the line of its nodes...

(NB, this is the finest British evaluation of the achievement, N.K.)


 

Airy to Sheepshanks RAS, McA 33:11

Royal Observatory, Greenwich, 1846 Dec 17.

Dear Sheepshanks,

Concerning the radius vector of Uranus -

The error was certain as to sign. It was determined with reasonable accuracy as to magnitude (perhaps the probable error might be 1/6 or 1/8 of the whole).

Now, suppose that Adams' elements which gave longitude-corrections had given a wrong sign for the correction of the radius vector, What would his theory have been worth?

_____________

The alternation of signs of errors + - in longitude does not exclude any other hypothesis than that of an exterior planet. If the law of force differed slightly from that of inverse square of the distance (of which two years ago there was great probability) and if tables were calculated strictly on the law of inverse square of distance (as was done in existing tables) then the discordances in longitude would have the alternate signs + -.


Adams to Sheepshanks 1846 Dec 17 RAS

... it is pointed out in my second letter to Mr Airy that my 1st solution did give the correction of Radius Vector very nearly agreeing with Obsn. & with respect to the 2nd I am surprised that any one should imagine that after having obtained the elements of the orbit of the disturbing planet from the perturbations in longitude, I was unable to perform so simple & direct an operation as the calculation from these elements of the corresponding correction of the radius vector. - In fact, in the more usual way of calculating the perturbations those of the Radius Vector are computed first & those of longitude derived from them, and this was the method which I actually followed in my first solution. The formulae for this purpose are well known & are given in Pontécoulant...


Challis to The Athenaeum Cambridge Dec 17

p.1300 No. 999, Dec 19

... M.Leverrier made another attempt to form tables [of Uranus] and again proved the impossibility. The single important result of the communication to the Paris Academy, on Nov. 10, 1845, was the obtaining of correct values of the tabular errors...

Again, as to the error of radius vector: - it is quite impossible that the longitude could be corrected during a period of at least 130 years independently of correction of the radius vector. If this might be done on the Ptolemaic system it cannot be done on that of Newton. The investigation of one necessarily involves that of the other. Mr Adams actually employed a method of calculation which required him to compute the co-efficients of the expression for error of radius vector, before computing the co-efficients of the expression for errors of longitude... M.Leverrier's communication to the Paris Academy on August 31st- which really gave good grounds for instituting a search - did not reach this country by the ordinary channels of information till after the planet was actually discovered...


Challis to Airy McA 33:12

Cambridge Observatory Dec 19. 1846

Why did not Adams answer your question? I know that he is extremely tardy about writing, & that he pleaded guilty to this fault. He experiences also a difficulty, which all young writers feel more or less, in putting into shape and order, what he has done, and well done, so as to convey an adequate idea of it to others by writing. After receiving your questions it occurred to him that it would be well for him to send you a full account of his methods of calculation, & that he might send the answer at the same time. I believe that nothing but procrastination in fulfilling this intention, was the reason of his not sending an answer at all. I have always found him more ready to communicate orally than by writing. It will hardly be believed that before I began my observations I had seen nothing of this in writing respecting the New Planet, except the elements which he gave me in September written on a small piece of paper without date.

I first got an idea of the nature & value of his Researches by an abstract which he drew up to produce at trhe meeting of the British Association at Southampton. The public would hardly take such a reason as that I have mentioned to be the true reason for his not answering your question, and I fear, therefore, a hiatus must remain in the History.


J.Herschel to R.Jones RS HS 22:295

1846 December [no date]

Adams's Memoir is very admirable. He has taken over a perfectly legitimate straightforward way of getting at his equations of condition (at first I was not quite satisfied about this - but I see all is quite as it should be) and his combinations are exceedingly skilful and masterly. On the other hand so are LeVerrier's and he takes a wider sweep in the whole conduct of his work. He goes into the question by clearing the ground ab initio by a preliminary total reconstruction of the theory of Uranus - a total reformation of the tables - a total reduction of all the observations - a total recalculation of all the places (300 in all [?]) and a comparison of them with (not Bouvard's old tables but) his newer theory. Hence he concludes positively and on sure grounds that the anomalous perturbations of Uranus are no illusion no mistakes of calculation but a reality. So much for Uranus.

... It is a shame to make rivals and competitors of two men who ought to be sworn brothers. Adams has the acknowledged priority in point of time that nothing can shake but till the Planet was found it was only a physical hypothesis upon trial, and no one can truly deny also that LeVerrier shot fair, and brought down the bird. Now my view of the matter is that there is quite enough for both and if Adams is not to be praised because he is an Englishman! Why is Leverrier to be blackguarded because he is a Frenchman? * - Barring Newton's law of gravity (who never meddled with the planetary perturbations) What Englishman ever furnished the smallest tottle of a tool towards rigging out a man for such a struggle? It is all French du fond en comble [?] Clairaut, D'Alembert, Laplace, Lagrange, and more recently Poisson and Pontecoulant for the analysis and Bouvard for the tables, which though not quite correct were yet correct enough to raise the hue and cry. - The New Planet is as much Laplace's as it is either Leverrier's or Adams's.

Mercy on us. What an outpouring!

Ever yours truly,

J.J.W.Herschel

* [omission] Who made one and all of the formulae by which both have grappled the planet but Frenchmen?


Airy to Challis McA 33:13

R O Greenwich 1846. December 21

...But with regard to one part of your own published letter in the last Athenaeum, I must make one remark. There were two things to be explained, which might have existed each independently of the other, and of which one could be ascertained independently of the other: viz., error of longitude and error of radius vector. And there is no _ priori reason for thinking that a hypothsis which will explain the error of longitude will also explain the error of radius vector. If, after Adams had satisfactorily explained the error of longitude, he had (with the numerical values of the elements of the two planets so found) converted his formula for perturbation of radius vector into numbers, and if these numbers had been discordant with the observed numbers of discordance of radius vector, then the theory would have been false, not from any error of Adams', but from a failure in the law of gravitation.

On this question therefore turned the continuance or fall of the law of gravitation. This, it appears to me, has been totally overlooked in your letter. It was a question of vast importance.

... What could be the reason of Adams' silence, I could not guess. It was so far unfortunate that it interposed an effectual barrier to all further communication. It was clearly impossible for me to write to him again.


Sheepshanks to Herschel Dec 26 1846 RS: HS 16:55

15pp

My dear Sir John,

... Be that as it may, the whole evidence as to Leverrier was out, understood and believed, before anything was known of Adams,...

 


SUR LA DENOMINATION DE LA PLANETE NOUVELLEMENT DECOUVERTE

by W.Struve Poulkova, ce 17 (29) Dec. 1846, 4 pages, 1-4

La partie de calendrier que publie, chacque annee, l'Academie des sciences de St.-Petersbourg, est redigree a l'Observatoire central de Poulkova. Dans le calendrier de l'annee 1847, la planete transuranienne a du etre mentionee. Elle s'y trouve aux pages 3, 48 at 49, sous la nomme de "Neptune" avec la signe du trident .

Une lettre de M.Le Verrier a M.O.Struve, datee du premier Octobre, nous a determinee a adopter ce nom. M. Le Verrier ecrit: "Le Bureau des longitudes s'est prononcee pour Neptune, le signe un trident. Je repousse le denomination de Janus; il n'y a aucune raison de croire que cette planete est la derniere du systeme solaire... [they were too late to adjust their calendar after Arago altered the name to 'LeVerrier', and don't like it anyway, N.K.]

Mis l'histoire impartiale, dans l'avenir, citera honourablement et a cote de M.Le Verrier, aussi le nom de M.Adams, et reconnaitra deux individus qui ont decouvert, l'un independament de l'autre, la planete au-dela d'Uranus. C'est ainsi qu'elle attribue la decouverte du calcul infinitesimal a Leibniz et a Newton...

En consequence, nous conserverons le nom de Neptune et nous ne l'abandonnerons que lorsque, dans la suite, la voix generale se sera decidee en favour d'un autre nom.

 


Herschel to Whewell Dec 29 1946 RS HS 22:294, 18:209

My dear Whewell,

... On the other hand Galle looked for it and found it on the sole ground of Leverrier's place, while Challis cannot shew that he looked for it (when at last he did so) purely and simply by Adams's. When he began to look he had already a knowledge of Leverrier's results, and he did not find it till after Galle had done so - for I do not call finding an individual object merely including it in a crowd of others (without knowing that it is there, and rather suspecting it not to be) with an intention of examining them at leisure to ascertain if it be among them or not - Nobody but Sheepshanks will ever say that Challis found it before Galle.

Until the planet was actually seen and shewn to be a planet - there was no discovery - except in so far as a successful physical hypothesis is one.- Certain motions have to be accounted for. A and B unknown to each other frame an hypothesis to account for it - A does - earlier than B - B does subsequently to A but more thoroughly - goes more into detail - finds it satisfy all minutiae. Assuredly A has gone a certain way to establish the hypothesis - many may have been induced by him to believe it true - many more by B's enquiries. - But before it can be received as an established hypothesis and called a discovery there is yet a step - it has to be tried whether other rival hypotheses will not do as well or better - till this has been done - till men's minds are made up to call the "Theory" - a "fact" there is no discovery - The sight of the actual thing of course forces them to do so at once.

On the back of what is presumably JH's copy of this letter, he has written in pencil:

God forgive me for writing in this way - The truth lies on the other side & Adams is the 1st theoretical discoveror of Neptune. The whole thing was marred and ** by Airy's indefensible reticence. On him be the responsibility of the (temporary) transferring of one of the brightest stars of [?] Britain's scientific ** to France.


Dec 30 Airy to A. De Morgan R O Greenwich 1846 Dec 30

My dear Sir,

Perhaps you have read the Mechanics Magasine, if not, I hope you will see the No. for December 26: there is the most singular piece of insanity in the history of the New Planet that I could have conceived. Yours very truly,


Herschel to Airy McA 33:14

1847 Jan 7

... I have within these 2 days got Le Verrier's Book - and I must say my impression is one of unbounded admiration. There is no part of the subject shied or slurred over - a tabula rasa - and a total reconstruction with a view from the beginning to the crowning pinnacle of the whole edifice. It is an Epic Poem complete in beginning middle & end with a catastrophe [sic] such as could not possibly be heightened by any additional circumstances. I am sorry for Adams & for England, but it would really have been a pity that so superb a struggle should not have been crowned with victory as a spectacle for Gods & men.


Sheepshanks to Schumacher Jan 11 1847 McA 34:16

My dear Sir,

....We had a long and rather warm discussion at our Society on the 8th _ propos of the medal. It ended, oddly enough in our not being able to give one because our rules don't allow us to give two. I suppose this will be alluded to at our annual meeting in February; but it is difficult to say what will be the result, nor, (now the main fact are known) does it much matter..... M. Arago has carried his power of nomenclature too far in raising a modern to be a companion with the heathen deities. The usage only gives a choice among the inhabitants of Olympus. We all call Uranus, Uranus. The "Georgian" was retained in the Nautical Alamanc by a weak deference to the wish of Herschel's doating son. Sir John worships his father & we almost adore Sir John. But the "Georgian" will go the way of all flesh & disappear from the N.A. before long.

 


Airy to LeVerrier McA Box 33:15

R O Greenwich 1847 Jan 12

.. I intended my paper as a history of all that I know bearing upon this wonderful discovery: and I wish that you or some person well acquainted with what has been done in France would write your portion of the history.

I very much wish that you would pay a visit to England. It would gratify me very much to have the pleasure of receiving you in my house. I am sure you would find that in England, not only among men of accurate science but also among the people generally, there is no national feeling adverse to the respect due to you: which is not incompatible with the assertion of some claims in favour of Mr Adams. Since your book arrived, I have conversed on it with only two competent judges of its merit, Sir John Herschel and Sir J.W.Lubbock: and they regard it with the most unbounded admiration.

Will you now permit me to mention a subject of the utmost delicacy, which I mention now in the most private way only because I am confident that, if it is not now mentioned privately, it will soon be mentioned publicly: I mean the name of the Planet. - From my conversation with lovers of astronomy in England and from my correspondence with astronomers in Germany, I find that the name assigned by M. Arago is not well received. They think, in the first place, that the character of the name is at variance with that of the names of all the other planets. They think in the next place that M.Arago as your delegate, could do only what you could do, and that you would not have given the name which Mr Arago has given. They are all desirous of receiving a mythological name selected by you.

In these feelings I do myself share. It was believed at first that you approved of the name Neptune, and on that supposition we have used the name Neptune when it was necessary to give a name. Now if it was understood that you still approved of the name Neptune (or Oceanus as some of my English mythologists suggested - or any other of the same class), I am sure that all England and Germany would adopt it at once. I am not sure that they will adopt the name which M.Arago has given.


Airy to C.Wentworth Dilke R O Greenwich 1847 Jan 13

Dear Sir,

I am much obliged by your giving me the opportunity of perusing the letters of your Paris Correspondent relating to the New Planet; I now return them. You may depend on my caution with regard to the writer's name.

I received yesterday the National of Oct 8, 14 & 21. I had before seen the section of that of the 21, which Mr Arago officially disclaimed in a letter to me - which letter I communicated to the Athenaum of the following week. I am told that Mr Arago moved the expulsion of the National editor from the meeting soon after the article, but that his motion was rejected. The whole series is very interesting.

Now, most astronomers dislike the name Le Verrier, as indelicate on the part of Le Verrier's deputy, and as alien in its derivation from all other planetary names. And we only want a fair degree of authenticity for Le Verrier's public approval of the name Neptune to adopt it at once.

 


Herschel to Adams 1847 Jan 18 JCA 9:15 not RGONE

Dear sir,

In this point of view (and setting aside all question of rivalry and competition between two men whose names will go down indisputably linked together to the latest posterity and between whom, if even, there ought to be a brotherhood of mutual admiration and regard) I can not help considering it as fortunate for science that this should have happened. All idea of a lucky guess - a mutual destruction of conflicting errors - of a right result got at by wrong means is precluded - and the most reluctant to accord any merit to theories must be bound to admit that in this matter at least theories are facts. "In the mouth of two witnesses shall a thing be established." - and the thing to be established seems to me to be less that such a body exists (though there is a fine part) but the maturity of a science which, beyond all power of gainsaying or cavil could lend two different enquiries independent of and unknown to each other to so coincident & exact a prediction of it in numero pondere et mensura.

 


Struve to Challis Pulkova Observatory 23 Jan/4 Feb 1847

IoA, V

... the name of Le Verrier would be against the accepted analogy and against historical truth, as it can not be denied that Mr Adams has been the first theoretical discoverer of that body, though not so happy to effect a direct ** of his indications.


Airy to Adams Jan 25 JCA 2:3 McA 33:16

Dear Sir,

In your paper on the New Planet, you express a wish that the manuscripts of Flamsteed's observations would be examined with refrence to the 1690 observations. I have carefully compared the MSS and the printed volume for all the days in 1690 and 1715 on which observations of Uranus were made, and I find that (with the exception of some trifling matter in the description of the stars) the printed volume is an exact and accurate copy of the MSS. The Index Error is not included in the MSS.

There is not the smallest appearance of any thing suspicious about the 1690 observations.

(NB, There was a problem in explaining the 1690 perturbation, NK)

 


LaVerrier to Airy Paris Jan 29 1847 RGO McA 33:17

Monsieur et cher Confrere,

J'ai lu avec attention la notice historique que vous avez presentee a la Societe Astronomique. Je vous remercie des termes dans lesquels vous avez parle de mon travail et de ce que votre derniere lettre renferme d'obligeant a ce sujet. Vous etes, Monsieur, du petit nombre des astronomes a qui la mechanique celste est familiere....Apres que j'eus donne mes memoires, et l'orsque je fus convaincu qu'on trouverait la planete ou j'avais dit, je crus naivement qu'on l'appelerait, Planete de Le Verrier, comme dit Comete de Halley, Comete d'Encke, Etc. Voila tout.

quand la planee fut trouvee, il fut proposee par le Bureau des Longitudes de l'appeler Neptune. Je ne faisais point partie du Bureau a cette epoque, et je ne l'avais pas charge de cela. En ecrivant a divers astronomes, je leur dis ce que le Bureau avait fait; mais sans ajouter ni blame ni approbation.

(NB, There is doubt whether the Board of Longitude had any part in choosing the name., NK)

 


Whewell to Airy Feb 8 1847

Have you astronomers decided yet the name of the new planet?

Airy writes at base: No name is yet well received for the Planet.

 

Airy to Athenaeum Name of the New Planet

R O Greenwich Feb 18

I do think with Mr Struve that the decision of a deputy is far less binding than that of the original discoveror: and I think it particularly necessary in the present instance to distinguish between these powers, because an attempt (which I must characterise as indelicate) has been made by the deputy to perform an act which was beyond the power of his principal, viz. to attach to the planet a name which no one in the position of a principal would have dared to attach.

 


Airy to Lev. McA Box 34:1

Royal Observatory, Greenwich, 1847 Feb 28

My dear Sir,

.. In my last letter I stated to you the difficulty in which I found myself, and in which nearly all the astronomers of Europe found themselves, with regard to the name of the new planet. I hoped that perhaps you might give me some sanction for the adoption of a mythological name. Your reply, which was conceived in terms of the utmost frankness, clearly showed to me that you were unable to make the change which appeared desirable. I determined therefore to take no positive step in adopting a name for the the planet until circumstances should compel me to do so. These circumstances, I think, have arrived: the reports of the principal astronomers of the North of Europe reached me about 12 days ago; and the determination, to which they had come, agreed, as I hear, with the wish of my English friends in general. I therefore definitely adopted the name Neptune, and I published this adoption in the number of the Athenaeum of which I enclose parts.

 


Babbage to RAS Council RAS 12th March

As I take a warm interest in the success and character of the Astron. Society I am anxious to be permitted very shortly to state the course I should have advocated.

1st. That the modern law relating to discoveries is, that they take their date from the time of their first publication to the world

In this case I think there can be no doubt as to priority of publication.

... 2nd. I concur entirely with the majority of the late council that the last medal ought to have been awarded to M. Le Verrier. And I much regret that the small minority of that council should have availed themselves of a privilege conferred upon them by the Society to prevent the awarding of medals to any discovery not eminently fit for them, into a means of preventing any such award in the strongest case which has yet occurred during the existence of the Astronomical Society.


Proc. Amer. Acad. Arts & Sciences, March 16, 1847

ON THE NEW PLANET NEPTUNE

Professor Peirce communicated to the Academy the following notice of the computations of Mr Sears C.Walker

'The inequality of (2μ-μ'), if the mean distance is nearly 30, is the most remarkable yet discovered in the primary solar system'

From differences in orbit, the conclusion 'the planet Neptune is not the planet to which geometrical analysis had directed the telescope... Its discovery by Galle must be regarded as a happy accident'

... It is not, however, a necessary conclusion that Neptune will not account for the perturbations of Uranus, for its probable mean distance of about 30 is so much less than the limits of previous researchers, that no inference from them can safely extend to it. An important change, indeed, in the character of the perturbations takes placed near the distance 35.3; so that the continuous law by which such inferences are justified is abruptly broken at this point, and it was hence an oversight in M. Le Verrier to extend his inner limit to the distance 35. A planet at the distance 35.3 would revolve around the sun in 210 years, which is exactly two and a a half times the period of the revolution of Uranus. Now, if the times of the revolution of the two planets were exactly as 2 to 5, the effects of their mutual influence would be peculiar and complicated, and even a near approach to this ratio gives rise to those remarakable irregularities of motion which are exhibited in Jupiter and Saturn, and which greatly perplexed geometers until they were traced to their origin by Laplace.

The observed distance 30, which is probably not very far from the mean distance, belongs to a region which is even more interesting in reference to Uranus than that of 35.3. The time of revolution which corresponds to the mean distance 30.4 is 168 years, being exactly double the year of Uranus, and the influence of a mass revolving in this time would give rise to very singular and marked irregularities in the motions of its orbit. The effect of a near approach to this ratio in the mean motions is partially developed by Laplace, in his theory of the motions of the three inner satellites of Jupiter. The whole perturbation arising from this source may be divided into two portions or inequalities, one of which, having the same period with the time of revolution of the inner planet, is masked to a great extent behind the ordinary elliptic motions, while the other has a very long period, and is exhibited for a great length of time under the form of a uniform increase or diminution of the mean motion of the disturbed planet. But it is highly probable that the case of Neptune and Uranus is not merely that of a near approach to the ratio of 2 to 1 in their times of revolution, but that this ratio is exactly preserved by those planets...


 

Washington Daily National Intelligencer 1847 March 26

LE VERRIER'S PLANET

We have been favoured with the following extracts from a letter from Professor BENJAMIN PIERCE, of Harvard University...

From the most careful examination of the observations which have been made upon (Neptune?) I am firmly convinced that it is not the planet predicted by analysis, so that its discovery must be regarded as a happy accident... I may safely go further, and state that the investigation of the effect of this planet upon Uranus is not included in the researches of either LeVerrier or Adams, and this interesting field of inquiry is yet to be explored... With such a mean motion [one half that of Uranus] some of the irregularities of motion will become extraordinarily large....

I would not have you suppose that I am disposed to contest in the least the greatness of Le Verrier's genius. I have studied his writings with infinite delight, and am ready to unite with the whole world in doing him homage, as the founder of a wholly new department of invisible astronomy.


Adams to Airy McA 34:2

St John's Coll. 28th April, 1847

I have lately calculated a new set of elements, supposing the star which, as noticed by Messr's Walker & Petersen, was observed by Lalande on May 10. 1795 but is now missing, to be the planet Neptune. The elements founded on a combination of this with the modern observations confirm my previous results & give an approximate value of the eccy. & long. of perihelion, which were left doubtful by my former solution... I am going to write to Mr Stratford to suggest that this would be a very proper occasion for altering the name "Georgian" in the Nautical Almanac into "Uranus" in order to conform to the general usage among Astronomers all the world over.


 

Airy to Adams 1847 April 29 JCA 2:4 not RGONE

... I shall be anxious to see your calculation of perturbations with the new elements, and to see the whole of your discussion of the mathematical causes of the very near agreement of the predicted place with the observed place.


Roderick Muchinson to Airy Paris 21 May 1847 McA 34:3

... It appears to me to be clear, that Arago had nothing whatever to do with the suggestion of the name "Planète Leverrier". He had, on the contrary, agreed with M.Leverrier, that it should be called Neptune, & the memoir calling it was actually printed & taken to the press by M.L.. The latter called soon after and began lamenting about the name & saying "on m'a dit que ..." ... On this Arago got into a rage with his protege & wheeled him off. The next day L. came back & throwing himself on Arago's mercy & goodness of heart, implored him to adopt the name Leverrier in order to serve him as a friend & a fellow countryman. Thus appealed to "en misericorde", Arago assented, but on the condition that Uranus should always be called (as he A. had previously termed it) Planete Herschel.

[L. then fails to accord with this, and prints a memoir about 'Uranus'] ... a quarrel takes place... a variety of intrigues ... as the board of Longitude and all the Astronomical section are hostile to Leverrier...