Of private history: There was the usual winter visit to Playford.—In
April he made a short trip to Cornwall with his daughter Annot.—In
June he was appointed a Companion of the Bath, and was presented at
Court on his appointment.—Mrs Airy was staying with her daughter, Mrs
Routh, at Hunstanton, during June, her state of health being somewhat
improved.—From August 1st to 28th he was chiefly in Cumberland, at
Barrow House, and at Grange, Borrowdale, where his son Osmund was
staying for a holiday.
1872
"From the Report to the Board of Visitors it appears that 'The Normal Siderial Clock for giving sidereal time by galvanic communication to the Astronomical Observatory was established in the Magnetic Basement in 1871, June; that locality being adapted for it on account of the uniformity of temperature, the daily changed of temperature rarely exceeding 1° Fahrenheit. Its escapement is one which I suggested many years ago in the Cambridge Transactions; a detached escapement, very closely analogous to the ordinary chronometer escapement, the pendulum receiving an impulse only at alternate vibrations…. The steadiness of rate is very far superior to any that we have previously attained.'—The aspect of railway enterprise is at present favourable to the Park and to the Observatory. The South-Eastern Railway Company has made an arrangement with the Metropolitan Board of Works for shifting the course of the great Southern Outfall Sewer. This enables the Company to trace a new line for the railway, passing on the north side of London Street, at such a distance from the Observatory as to remove all cause of alarm. I understand that the Bill, which was unopposed, has passed the Committee of the House of Commons. I trust that the contest, which has lasted thirty-seven years, is now terminated.—The observations of 7 Draconis with the Water-Telescope, made in the autumn of 1871, and the spring of 1872, are reduced, the latter only in their first steps…. Using the values of the level scales as determined by Mr Simms (which I have no reason to believe to be inaccurate) the spring and autumn observations of 1871 absolutely negative the idea of any effect being produced on the constant of aberration by the amount of refracting medium traversed by the light.—The great Aurora of 1872 Feb. 4 was well observed. On this occasion the term Borealis would have been a misnomer, for the phenomenon began in the South and was most conspicuous in the South. Three times in the evening it exhibited that umbrella-like appearance which has been called (perhaps inaccurately) a corona. I have very carefully compared its momentary phenomena with the corresponding movements of the magnetometers. In some of the most critical times, the comparison fails on account of the violent movements and consequent faint traces of the magnetometers. I have not been able to connect the phases of aurora and those of magnetic disturbance very distinctly.—The Report contains a detailed account of the heavy preparations for the observation of the Transit of Venus 1874, including the portable buildings for the instruments, the instruments themselves (being a transit-instrument, an altazimuth, and an equatoreal, for each station), and first class and second-class clocks, all sufficient for the equipment of 5 stations, and continues thus: I was made aware of the assent of the Government to the wish of the Board of Visitors, as expressed at their last meeting, that provision should be made for the application of photography to the observation of the Transit of Venus. It is unnecessary for me to remark that our hope of success is founded entirely on our confidence in Mr De La Rue. Under his direction, Mr Dallmeyer has advanced far in the preparation of five photoheliographs…. The subject is recognized by many astronomers as not wholly free from difficulties, but it is generally believed that these difficulties may be overcome, and Mr De La Rue is giving careful attention to the most important of them.—I take this opportunity of reporting to the Board that the Observatory was honoured by a visit of His Majesty the Emperor of Brazil, who minutely examined every part."—After referring to various subjects which in his opinion might be usefully pursued systematically at the Observatory, the Report proceeds thus: "'The character of the Observatory would be somewhat changed by this innovation, but not, as I imagine, in a direction to which any objection can be made. It would become, pro tanto, a physical observatory; and possibly in time its operations might be extended still further in a physical direction.'—The consideration of possible changes in the future of the Observatory leads me to the recollection of actual changes in the past. In my Annual Reports to the Visitors I have endeavoured to chronicle these; but still there will be many circumstances which at present are known only to myself, but which ought not to be beyond the reach of history. I have therefore lately employed some time in drawing up a series of skeleton annals of the Observatory (which unavoidably partakes in some measure of the form of biography), and have carried it through the critical period, 1836-1851. If I should command sufficient leisure to bring it down to 1861, I think that I might then very well stop." (The skeleton annals here referred to are undoubtedly the manuscript notes which form the basis of the present biography. Ed.)—"On Feb. 23rd in this year I first (privately) formed the notion of preparing a numerical Lunar Theory by substituting Delaunay's numbers in the proper Equations and seeing what would come of it."
Of private history: There was the usual visit to Playford—in this year later than usual—from Feb. 4th to Mar. 4th. The letters written during this visit are, as usual, full of freshness and delight at finding himself in his favourite country village.—On June 5th he went to Barrow House, near Keswick, to be present at the marriage of his second son Hubert to Miss S. C. Langton, daughter of Z. Langton Esq., of Barrow House.—After the wedding he made a trip through the Trossachs district of Scotland with his daughter Annot, and returned to Greenwich on June 17th.
On the 26th June 1872 Airy was appointed a Knight Commander of the Most Honourable Order of the Bath: he was knighted by the Queen at Osborne on the 30th of July. In the course of his official career he had three times been offered Knighthood, and had each time declined it: but it seemed now as if his scruples on the subject were removed, and it is probable that he felt gratified by the public recognition of his services. Of course the occasion produced many letters of congratulation from his friends: to one of these he replied as follows: "The real charm of these public compliments seems to be, that they excite the sympathies and elicit the kind expressions of private friends or of official superiors as well as subordinates. In every way I have derived pleasure from these." From the Assistants of the Royal Observatory he received a hearty letter of congratulation containing the following paragraph. "Our position has naturally given us peculiar opportunities for perceiving the high and broad purposes which have characterized your many and great undertakings, and of witnessing the untiring zeal and self-denial with which they have been pursued."
* * * * *
On the 18th of March 1872 Airy was nominated a Foreign Associate of the Institut de France, to fill the place vacant by the death of Sir John Herschel. The following letter of acknowledgment shews how much he was gratified by this high scientific honour:
ROYAL OBSERVATORY, GREENWICH, 1872, March 23.
À Messieurs Messieurs ELIE DE BEAUMONT, et J.B. DUMAS, Secrétaires perpetuels de l'Académie des Sciences, Institut de France.