"As my reduction of observations was kept quite close, I now began to think of printing. In regard to the form I determined to adopt a plan totally different from that of any other observations which I had seen. The results were to be the important things: I was desirous of suppressing the separate wires of transits. But upon consulting Herschel and other persons they would not agree to it, and I assented to keeping them. I applied to the Press Syndicate to print the work, and on Nov. 10th at the request of T. Musgrave (afterwards Archbishop of York) I sent a specimen of my MS.: on Nov. 11th they granted 250 copies, and the printing soon commenced."

1829

"During a winter holiday at Playford I wrote out some investigations about the orbits of comets, and on Jan. 23rd 1829 I returned to Cambridge. The Smith's Prize Examination soon followed, in which I set a Paper of questions as usual. On Feb. 18th I made notes on Liesganig's geodetic work at the British Museum.

"I was naturally anxious now about the settlement of my salary and of the Observatory establishment. I do not know when the Syndicate made their Report, but it must have been in the last term of 1828. It recommended that the salary should be annually made up (by Grace) to L500: that an Assistant should be appointed with the assent of the Vice-Chancellor and dismissable by the Plumian Professor: and that a Visiting Syndicate should be appointed, partly official and partly of persons to be named every year by Grace. The Grace for adopting this Report was to be offered to the Senate on Feb. 27th. The passing of the Grace was exposed to two considerable perils. First, I found out (just in time) that a Senior Fellow of Trinity (G.A. Browne) was determined to oppose the whole, on account of the insignificant clause regarding dismissal of Assistants, which he regarded as tyrannical. I at once undertook that that clause should be rejected. Secondly, by the absurd constitution of the 'Caput' at Cambridge, a single M.A. had the power of stopping any business whatever, and an M.A. actually came to the Senate House with the intention of throwing out all the Graces on various business that day presented to the Senate. Luckily he mistook the hour, and came at 11 instead of 10, and found that all were dispatched. The important parts of the Grace passed without any opposition: but I mustered some friends who negatived that part which had alarmed G.A. Browne, and it was corrected to his satisfaction by a new Grace on Mar. 18th. I was now almost set at rest on one of the great objects of my life: but not quite. I did not regard, and I determined not to regard, the addition to my salary as absolutely certain until a payment had been actually made to me: and I carefully abstained, for the present, from taking any steps based upon it. I found for Assistant at the Observatory an old Lieutenant of the Royal Navy, Mr Baldrey, who came on Mar. 16.

"On May 4th I began lectures: there were 32 names. The Lectures were improving, especially in the optical part. I do not find note of the day of termination.—I do not know the actual day of publication of my first small volume of Cambridge Observations, 1828, and of circulation. The date of the preface is Apr. 27th 1829. I have letters of approval of it from Davies Gilbert, Rigaud, and Lax. The system which I endeavoured to introduce into printed astronomical observations was partially introduced into this volume, and was steadily improved in subsequent volumes. I think that I am justified, by letters and other remarks, in believing that this introduction of an orderly system of exhibition, not merely of observations but of the steps for bringing them to a practical result—quite a novelty in astronomical publications—had a markedly good effect on European astronomy in general.—In Feb. and March I have letters from Young about the Nautical Almanac: he was unwilling to make any great change, but glad to receive any small assistance. South, who had been keeping up a series of attacks on Young, wrote to me to enquire how I stood in engagements of assistance to Young: I replied that I should assist Young whenever he asked me, and that I disapproved of South's course.—The date of the first visitation of the (Cambridge) Observatory must have been near May 11th: I invited South and Baily to my house; South and I were very near quarrelling about the treatment of Young.—In a few days after Dr Young died: I applied to Lord Melville for the superintendence of the Nautical Almanac: Mr Croker replied that it devolved legally upon the Astronomer Royal, and on May 30th Pond wrote to ask my assistance when I could give any. On June 6th I was invited to the Greenwich Visitation, to which I believe I went on the 10th.

"I had long desired to see Switzerland, and I wished now to see some of the Continental Observatories. I was therefore glad to arrange with Mr Lodge, of Magdalene College (perhaps 10 years senior to myself), to make a little tour. Capt. W.H. Smyth and others gave me introductions. I met Lodge in London, and we started for Calais on July 27th 1829. We visited a number of towns in Belgium (at Brussels I saw the beginning of the Observatory with Quetelet), and passed by Cologne, Frankfort, Fribourg, and Basle to Zurich. Thus far we had travelled by diligence or posting: we now procured a guide, and travelled generally on foot. From the 13th to the 31st August we travelled diligently through the well-known mountainous parts of Switzerland and arrived at Geneva on the 31st August. Here I saw M. Gautier, M. Gambard, and the beginning of the Observatory. Mr Lodge was now compelled to return to Cambridge, and I proceeded alone by Chambery to Turin, where I made the acquaintance of M. Plana and saw the Observatory. I then made a tour through north Italy, looking over the Observatories at Milan, Padua, Bologna, and Florence. At Leghorn I took a passage for Marseille in a xebeque, but after sailing for three days the weather proved very unfavourable, and I landed at Spezia and proceeded by Genoa and the Cornici Road to Marseille. At Marseille I saw M. Gambart and the Observatory, and passed by Avignon, Lyons, and Nevers to Orleans, where I visited my old host M. Legarde. Thence by Paris, Beauvais, and Calais to London and Cambridge, where I arrived on the 30th October. I had started with more than L140 and returned with 2s. 6d. The expedition was in many ways invaluable to me.

"On my return I found various letters from scientific men: some approving of my method for the mass of the Moon: some approving highly of my printed observations, especially D. Gilbert, who informed me that they had produced good effect (I believe at Greenwich), and Herschel.—On Nov. 13th I gave the Royal Astronomical Society a Paper about deducing the mass of the Moon from observations of Venus: on Nov. 16th a Paper to the Cambridge Philosophical Society on a correction to the length of a ball-pendulum: and on Dec. 14th a Paper on certain conditions under which perpetual motion is possible.—The engravings for my Figure of the Earth in the Encyclopaedia Metropolitana were dispatched at the end of the year. Some of the Paper (perhaps much) was written after my return from the Continent.—I began, but never finished, a Paper on the form of the Earth supposed to be projecting at middle latitudes. In this I refer to the printed Paper which Nicollet gave me at Paris. I believe that the investigations for my Paper in the Encyclopaedia Metropolitana led me to think the supposition unnecessary.—On Nov. 6th I was elected member of the Geological Society.

"On Nov. 16th 1829 notice was given of a Grace to authorize payment to me of L157. 9s. 1d., in conformity with the regulations adopted on Feb. 27th, and on Nov. 18th the Grace passed the Senate. On Nov. 19th the Vice-Chancellor wrote me a note enclosing the cheque. On Nov. 23rd (practically the first day on which I could go) I went to London and travelled to Edensor, where I arrived on the 26th. Here I found Richarda Smith, proposed to her, and was accepted. I stayed there a few days, and returned to Cambridge."

1830

"On Jan. 25th 1830 the Smith's Prize Paper was prepared. I was (with my Assistant, Mr Baldrey) vigorously working the Transit Instrument and its reductions, and gradually forming a course of proceeding which has had a good effect on European Astronomy. And I was preparing for my marriage.

"On Mar. 11th I started with my sister to London, and arrived at Edensor on the afternoon of the 14th. On the 17th I started alone for Manchester and Liverpool. Through Mr Mason, a cotton-spinner at Calver, near Edensor, I had become acquainted with Mr John Kennedy of Manchester, and I had since 1824 been acquainted with Dr Traill of Liverpool. Amongst other things, I saw the works of the Manchester and Liverpool Railway, then advancing and exciting great interest, and saw George Stephenson and his son. On Mar. 24th I was married to Richarda Smith by her father in Edensor. We stopped at Edensor till Apr. 1st, and then started in chaises by way of Newark and Kettering (where we were in danger of being stopped by the snow), and arrived at Cambridge on Apr. 3rd.

"I was now busy in preparing for lectures, especially the part of the optical lectures which related to the theory of interferences and polarization. I think it was now that my wife drew some of my lecture pictures, exhibiting interference phenomena. My lectures began on Apr. 26th and finished on May 24th. The number of names was 50. They were considered an excellent course of lectures.

"May 9th is the date of my Preface to the 1829 Observations: all was then printed. Apparently I did not go to the Visitation of the Greenwich Observatory this year.—I was at this time pressing Tulley, the optician, about an object-glass for the Mural Circle.—A new edition of my 'Tracts' was wanted, and I prepared to add a Tract on the Undulatory Theory of Light in its utmost extent. The Syndicate of the University Press intimated through Dr Turton that they could not assist me (regarding the book as a second edition). On July 10th I have some negociation about it with Deighton the bookseller.—On May 18th I have a note from Whewell about a number of crystals of plagiedral quartz, in which he was to observe the crystalline indication, and I the optical phenomena.—The Report of the Syndicate for visiting the Observatory is dated June 18th: it is highly laudatory.—The Proctor (Barnard of King's College) requested me to name the Moderator for the next B.A. Examination: I named Mr Challis.

"On June 14th my wife and I went, in company with Professor and Mrs Henslow, to London and Oxford; at Oxford we were received in Christchurch College by Dr and Mrs Buckland. My wife and I then went to Bedford to visit Capt. and Mrs Smyth, and returned to Cambridge on the 23rd. On July 5th we went on a visit to my mother and uncle at Playford. While there I took a drive with my uncle into some parts near the valley of the Gipping, in which I thought that the extent of the chalk was inadequately exhibited on Greenough's map, and communicated my remarks to Buckland.

"I find letters from Dr Robinson and Col. Colby about determining longitudes of certain observatories by fire signals: I proposed chronometers as preferable. Also from Herschel, approving of my second volume of observations: and from F. Baily, disclaiming the origination of the attack on the old Nautical Almanac (with which I suppose I had reproached him). On July 30th I received a summons from South to a committee for improving the Nautical Almanac; and subsequently a letter from Baily about Schumacher's taking offence at a passage of mine in the Cambridge Observations, on the comparative merits of Ephemerides, which I afterwards explained to his satisfaction.

"On Aug. 24th my wife and I started for Edensor, and after a short stay there proceeded by Manchester to Cumberland, where we made many excursions. We returned by Edensor, and reached Cambridge on Oct. 6th, bringing my wife's sister Susanna on a visit. My mother had determined, as soon as my intention of marriage was known to her, to quit the house, although always (even to her death) entertaining the most friendly feelings and fondness for my wife. It was also judged best by us all that my sister should not reside with us as a settled inhabitant of the house. They fixed themselves therefore at Playford in the farm-house of the Luck's Farm, then in the occupation of my uncle Arthur Biddell. On Oct. 21st I have a letter from my sister saying that they were comfortably settled there.

"In this month of October (principally, I believe) I made some capital Experiments on Quartz, which were treated mathematically in a Paper communicated in the next year to the Cambridge Philosophical Society. In some of these my wife assisted me, and also drew pictures.—On Nov. 15th the Grace for paying me L198. 13s. 8d. to make my income up to L500 passed the Senate.—I made three journeys to London to attend committees, one a committee on the Nautical Almanac, and one a Royal Society Committee about two southern observatories.—On Dec. 31st I have a letter from Maclear (medical practitioner and astronomer at Biggleswade) about occultations.—In this December I had a quartz object-glass by Cauchaix mounted by Dollond, and presented it to the Observatory.—In this December occurred the alarm from agrarian fires. There was a very large fire at Coton, about a mile from the Observatory. This created the most extraordinary panic that I ever saw. I do not think it is possible, without having witnessed it, to conceive the state of men's minds. The gownsmen were all armed with bludgeons, and put under a rude discipline for a few days."

1831

"On Jan. 4th I went with my wife, first to Miss Sheepshanks in London, at 30, Woburn Place, and next to the house of my wife's old friend, the Rev. John Courtney, at Sanderstead, near Croydon. I came to London on one day to attend a meeting of the new Board of Visitors of the Greenwich Observatory. Formerly the Board of Visitors consisted of the Council of the Royal Society with persons invited by them (in which capacity I had often attended). But a reforming party, of which South, Babbage, Baily and Beaufort were prominent members, had induced the Admiralty to constitute a new Board, of which the Plumian Professor was a member. Mr Pond, the Astronomer Royal, was in a rather feeble state, and South seemed determined to bear him down: Sheepshanks and I did our best to support him. (I have various letters from Sheepshanks to this purpose.)—On Jan. 22nd we returned to Cambridge, and I set an Examination Paper for Smith's Prizes as usual.—On Jan. 30th I have a letter from Herschel about improving the arrangement of Pond's Observations. I believe that much of this zeal arose from the example of the Cambridge Observations.

"On Feb. 21st my Paper 'On the nature of the light in the two rays of Quartz' was communicated to the Philosophical Society: a capital piece of deductive optics. On Mar. 2nd I went to London, I suppose to attend the Board of Visitors (which met frequently, for the proposed reform of Pond's Observations, &c.). As I returned on the outside of the coach there occurred to me a very remarkable deduction from my ideas about the rays of Quartz, which I soon tried with success, and it is printed as an Appendix to the Paper above mentioned. On Mar. 6th my son George Richard was born."

Miscellaneous matters in the first half of this year are as follows:

"Faraday sends me a piece of glass for Amici (he had sent me a piece before).—On Apr. 9th I dispatched the Preface of my 1830 Observations: this implies that all was printed.—On Apr. 18th I began my Lectures and finished on May 24th. There were 49 names. A very good series of lectures.—I think it was immediately after this, at the Visitation of the Cambridge Observatory, that F. Baily and Lieut. Stratford were present, and that Sheepshanks went to Tharfield on the Royston Downs to fire powder signals to be seen at Biggleswade (by Maclear) and at Bedford (by Capt. Smyth) as well as by us at Cambridge.—On May 14th I received L100 for my article on the Figure of the Earth from Baldwin the publisher of the Encyclopaedia Metropolitana.—I attended the Greenwich Visitation on June 3rd.—On June 30th the Observatory Syndicate made their report: satisfactory.

"On July 6th 1831 I started with my wife and infant son for Edensor, and went on alone to Liverpool. I left for Dublin on the day on which the loss of the 'Rothsay Castle' was telegraphed, and had a bad voyage, which made me ill during my whole absence. After a little stay in Dublin I went to Armagh to visit Dr Robinson, and thence to Coleraine and the Giant's Causeway, returning by Belfast and Dublin to Edensor. We returned to Cambridge on Sept. 9th.

"Up to this time the Observatory was furnished with only one large instrument, namely the 10-foot Transit. On Feb. 24th of this year I had received from Thomas Jones (62, Charing Cross) a sketch of the stone pier for mounting the Equatoreal which he was commissioned to make: and the pier was prepared in the spring or summer. On Sept. 20th part of the instrument was sent to the Observatory; other parts followed, and Jones himself came to mount it. On Sept. 16th I received Simms's assurance that he was hastening the Mural Circle.—In this autumn I seriously took up the recalculation of my Long Inequality of Venus and the Earth, and worked through it independently; thus correcting two errors. On Nov. 10th I went to Slough, to put my Paper in the hands of Mr Herschel for communication to the Royal Society. The Paper was read on Nov. 24th.—This was the year of the first Meeting of the British Association at York. The next year's meeting was to be at Oxford, and on Oct. 17th I received from the Rev. W. Vernon Harcourt an invitation to supply a Report on Astronomy, which I undertook: it employed me much of the winter, and the succeeding spring and summer.—The second edition of my Tracts was ready in October. It contained, besides what was in the first edition, the Planetary Theory, and the Undulatory Theory of Light. The Profit was L80.—On Nov. 14th I presented to the Cambridge Philosophical Society a Paper 'On a remarkable modification of Newton's Rings': a pretty good Paper.—In November the Copley Medal was awarded to me by the Royal Society for my advances in Optics.—Amongst miscellaneous matters I was engaged in correspondence with Col. Colby and Capt. Portlock about the Irish Triangulation and its calculation. Also with the Admiralty on the form of publication of the Greenwich and Cape Observations."

1832

"In January my Examination Paper for Smith's Prizes was prepared as usual.—Two matters (in addition to the daily routine of Observatory work) occupied me at the beginning of this year. One was the translation of Encke's Paper in successive numbers of the Astronomische Nachrichten concerning Encke's Comet; the University Press printed this gratuitously, and I distributed copies, partly by the aid of Capt. Beaufort.—The other was the Report on Astronomy for the British Association, which required much labour. My reading for it was principally in the University Library (possibly some in London), but I borrowed some books from F. Baily, and I wrote to Capt. Beaufort about the possible repetition of Lacaille's Meridian Arc at the Cape of Good Hope. The Report appears to have been finished on May 2nd.—At this time the Reform Bill was under discussion, and one letter written by me (probably at Sheepshanks's request) addressed I think to Mr Drummond, Lord Althorp's secretary, was read in the House of Commons.

"Optics were not neglected. I have some correspondence with Brewster and Faraday. On Mar. 5th I gave the Cambridge Philosophical Society a Paper 'On a new Analyzer,' and on Mar. 19th one 'On Newton's Rings between two substances of different refractive powers,' both Papers satisfactory to myself.—On the death of Mr F. Fallows, astronomer at the Cape of Good Hope Observatory, the Admiralty appointed Mr Henderson, an Edinburgh lawyer, who had done some little things in astronomical calculation. On Jan. 10th I discussed with him observations to be made, and drew up his Official Instructions which were sent on Jan. 10th.—On Feb. 16th Sir James South writes that Encke's Comet is seen: also that with his 12-inch achromatic, purchased at Paris, and which he was preparing to mount equatoreally, he had seen the disk of Aldebaran apparently bisected by the Moon's limb.—Capt. Beaufort and D. Gilbert write in March about instructions to Dunlop, the astronomer at Paramatta. I sent a draft to Capt. Beaufort on Apr. 27th.

"The Preface to my 1831 Observations is dated Mar. 20th. The distribution of the book would be a few weeks later.—On May 7th I began my Lectures: 51 names: I finished on May 29th.—The mounting of the Equatoreal was finished some time before the Syndicate Visitation at the end of May, but Jones's charge appeared to be exorbitant: I believe it was paid at last, but it was considered unfair.—On June 2nd I went to London: I presume to the Greenwich Visitation.—I went to Oxford to the meeting of the British Association (lodging I think with Prof. Rigaud at the Observatory) on June 16th, and read part of my Report on Astronomy in the Theatre.

"On June 26th I started with my wife for the Highlands of Scotland. After a short stay at Edensor, we went by Carlisle to Glasgow, and through the Lake District to Inverness. Thence by Auchnanault to Balmacarra, where we were received by Mr Lillingstone. After an expedition in Skye, we returned to Balmacarra, and passed on to Invermoriston, where we were received by Grant of Glenmoriston. We then went to Fort William and Oban, and crossed over to Mull, where we were received by Maclean of Loch Buy. We returned to Oban and on to Edinburgh, where we made a short stay. Then to Melrose, where we were received by Sir D. Brewster, and by Edensor to Cambridge, where we arrived on Sept. 17th.

"I received (at Edinburgh I believe) a letter from Arago, writing for the plans of our observing-room shutters.—Mr Vernon Harcourt wrote deprecating the tone of my Report on Astronomy as related to English Astronomers, but I refused to alter a word.—Sheepshanks wrote in September in great anxiety about the Cambridge Circle, for which he thought the pier ought to be raised: I would have no such thing, and arranged it much more conveniently by means of a pit. On Oct. 9th Simms says that he will come with the circle immediately, and Jones on Sept. 29th says that he will make some alteration in the equatoreal: thus there was at last a prospect of furnishing the Observatory properly.—On Oct. 9th, I have Encke's thanks for the translation of the Comet Paper.—One of the desiderata which I had pointed out in my Report on Astronomy was the determination of the mass of Jupiter by elongations of the 4th satellite: and as the Equatoreal of the Cambridge Observatory was on the point of coming into use, I determined to employ it for this purpose. It was necessary for the reduction of the observations that I should prepare Tables of the motion of Jupiter's 4th Satellite in a form applicable to computations of differences of right-ascension. The date of my Tables is Oct. 3rd, 1832.—In October the Observatory Syndicate made their Report: quite satisfactory.

"On Oct. 20th Sheepshanks wrote asking my assistance in the Penny Cyclopaedia: I did afterwards write 'Gravitation' and 'Greenwich.' —Capt. Beaufort wrote in November to ask my opinion on the Preface to an edition of Groombridge's Catalogue which had been prepared by H. Taylor: Sheepshanks also wrote; he had objected to it. This was the beginning of an affair which afterwards gave me great labour.—Vernon Harcourt writes, much offended at some terms which I had used in reference to an office in the British Association.

"The Equatoreal mounting which Troughton and Simms had been preparing for Sir James South's large telescope had not entirely succeeded. I have various letters at this time from Sheepshanks and Simms, relating to the disposition which Sir James South shewed to resist every claim till compelled by law to pay it.—A general election of Members of Parliament was now coming on: Mr Lubbock was candidate for the University. On Nov. 27th I had a letter from Sedgwick requesting me to write a letter in the newspapers in favour of Lubbock; which I did. On Dec. 7th I have notice of the County voting at Newmarket on Dec. 18th and 19th: I walked there to vote for Townley; he lost the election by two or three votes in several thousands.

"The Mural Circle was now nearly ready in all respects, and it was known that another Assistant would be required. Mr Richardson (one of the Assistants of Greenwich Observatory) and Mr Simms recommended to me Mr Glaisher, who was soon after appointed, and subsequently became an Assistant at Greenwich.—On Dec. 24th I have a letter from Bessel (the first I believe). I think that I had written to him about a general reduction of the Greenwich Planetary Observations, using his Tabulae Regiomontanae as basis, and that this was his reply approving of it."

1833

"On Jan. 4th 1833 my daughter Elizabeth was born.—I prepared an examination paper for Smith's Prizes as usual.—On Jan. 5th I received notice from Simms that he had received payment (L1050) for the Mural Circle from the Vice-Chancellor. About this time the Circle was completely made serviceable, and I (with Mr Glaisher as Assistant) immediately began its use. A puzzling apparent defect in the circle (exhibiting itself by the discordance of zenith points obtained by reflection observations on opposite sides of the zenith) shewed itself very early. On Feb. 4th I have letters about it from Sheepshanks and Simms.—On Jan. 17th I received notice from F. Baily that the Astronomical Society had awarded me their Medal for my long inequality of Venus and the Earth: on Feb. 7th I went to London, I suppose to receive the Medal.—I also inspected Sir J. South's telescope, then becoming a matter of litigation, and visited Mr Herschel at Slough: on Feb. 12th I wrote to Sir J. South about the support of the instrument, hoping to remove one of the difficulties in the litigation; but it produced no effect.—Herschel wrote to me, from Poisson, that Pontecoulant had verified my Long Inequality.

"Mar. 12th is the date of the Preface to my 1832 volume of Observations: it was of course distributed a few weeks later.—In my Report on Astronomy I had indicated the Mass of Jupiter as a subject requiring fresh investigation. During the last winter I had well employed the Equatoreal in observing elongations in R.A. of the 4th Satellite. To make these available it was necessary to work up the theory carefully, in which I discovered some remarkable errors of Laplace. Some of these, for verification, I submitted to Mr Lubbock, who entirely agreed with me. The date of my first calculations of the Mass of Jupiter is Mar. 1st: and shortly after that I gave an oral account of them to the Cambridge Philosophical Society. The date of my Paper for the Astronomical Society is April 12th. The result of my investigations (which was subsequently confirmed by Bessel) entirely removed the difficulty among Astronomers; and the mass which I obtained has ever since been received as the true one.

"On Apr. 9th my wife's two sisters, Elizabeth and Georgiana Smith, came to stay with me.—On Apr. 22nd I began lectures, and finished on May 21st: there were 54 names. During the course of the lectures I communicated a Paper to the Philosophical Society 'On the calculation of Newton's experiments on Diffraction.'—I went to London on the Visitation of the Greenwich Observatory: the dinner had been much restricted, but was now made more open.—It had been arranged that the meeting of the British Association was to be held this year at Cambridge. I invited Sir David Brewster and Mr Herschel to lodge at the Observatory. The meeting lasted from June 24th to 30th. We gave one dinner, but had a breakfast party every day. I did not enter much into the scientific business of the meeting, except that I brought before the Committee the expediency of reducing the Greenwich Planetary Observations from 1750. They agreed to represent it to the Government, and a deputation was appointed (I among them) who were received by Lord Althorp on July 25th. On Aug. 3rd Herschel announced to me that L500 was granted.

"On Aug. 7th I started with my wife for Edensor. At Leicester we met Sedgwick and Whewell: my wife went on to Edensor, and I joined Sedgwick and Whewell in a geological expedition to Mount Sorrel and various parts of Charnwood Forest. We were received by Mr Allsop of Woodlands, who proved an estimable acquaintance. This lasted four or five days, and we then went on to Edensor.—On Aug. 15th Herschel wrote to me, communicating an offer of the Duke of Northumberland to present to the Cambridge Observatory an object-glass of about 12 inches aperture by Cauchaix. I wrote therefore to the Duke, accepting generally. The Duke wrote to me from Buxton on Aug. 23rd (his letter, such was the wretched arrangement of postage, reaching Bakewell and Edensor on the 25th) and on the 26th I drove before breakfast to Buxton and had an interview with him. On Sept. 1st the Duke wrote, authorizing me to mount the telescope entirely, and he subsequently approved of Cauchaix's terms: there was much correspondence, but on Dec. 28th I instructed Cauchaix how to send the telescope.—On our return we paid a visit to Dr Davy, Master of Caius College, at Heacham, and reached Cambridge on Oct. 8th.

"Groombridge's Catalogue, of which the editing was formally entrusted to Mr Henry Taylor (son of Taylor the first-assistant of the Greenwich Observatory), had been in some measure referred to Sheepshanks: and he, in investigating the work, found reason for thinking the whole discreditable. About May he first wrote to me on his rising quarrel with H. Taylor, but on Sept. 7th he found things coming to a crisis, and denounced the whole. Capt. Beaufort the Hydrographer (in whose office this matter rested) begged me with Baily to decide upon it. We did not at first quite agree upon the terms of investigation &c., but after a time all was settled, and on Oct. 4th the Admiralty formally applied, and I formally accepted. Little or nothing had been done by Mr Baily and myself, when my work was interrupted by illness.

"Sheepshanks had thought that something might be done to advance the interests of myself or the Observatory by the favour of Lord Brougham (then Lord Chancellor), and had urged me to write an article in the Penny Cyclopaedia, in which Lord Brougham took great interest. I chose the subject 'Gravitation,' and as I think wrote a good deal of it in this Autumn: when it was interrupted by my illness.

"On Dec. 9th 1833, having at first intended to attend the meeting of the Philosophical Society and then having changed my mind, I was engaged in the evening on the formulae for effects of small errors on the computation of the Solar Eclipse of 1833. A dizziness in my head came on. I left off work, became worse, and went to bed, and in the night was in high fever with a fierce attack of scarlet fever. My wife was also attacked but very slightly. The first day of quitting my bedroom was Dec. 31st. Somewhere about the time of my illness my wife's sister, Susanna Smith, who was much reduced in the summer, died of consumption.

"Miscellaneous notes in 1833 are as follows: Henderson (at the Cape) could not endure it much longer, and on Oct. 14th Stratford writes that Maclear had just sailed to take his place: Henderson is candidate for the Edinburgh Observatory.—Stratford writes on Dec. 2nd that the Madras observations have come to England, the first whose arrangement imitates mine.—On Nov. 3rd Herschel, just going to the Cape, entrusted to me the revisal of some proof sheets, if necessary: however it was never needed.—In November I sat for my portrait to a painter named Purdon (I think): he came to the house and made a good likeness. A pencil portrait was taken for a print-seller (Mason) in Cambridge: it was begun before my illness and finished after it.—I applied through Sheepshanks for a copy of Maskelyne's Observations, to be used in the Reduction of the Planetary Observations: and on Dec. 24th (from my bedroom) I applied through Prof. Rigaud to the Delegates of the Clarendon Press for a copy of Bradley's Observations for the same. The latter request was refused. In October I applied to the Syndics of the University Press for printed forms for these Reductions: the Syndics agreed to grant me 12,000 copies."

1834

"On Jan. 11th 1834 I went with my wife to London for the recruiting of my strength. We stayed at the house of our friend Miss Sheepshanks, and returned on Feb. 13th.—I drew up a Paper of Questions for Smith's Prizes, but left the whole trouble of examination and adjudication to Professor Miller, who at my request acted for me.—While I was in London I began to look at the papers relating to Groombridge's Catalogue: and I believe that it was while in London that I agreed with Mr Baily on a Report condemnatory of H. Taylor's edition, and sent the Report to the Admiralty. The Admiralty asked for further advice, and on Feb. 28th I replied, undertaking to put the Catalogue in order. On Mar. 17th Capt. Beaufort sent me all the papers. Some time however elapsed before I could proceed with it.

"There was in this spring a furious discussion about the admission of Dissenters into the University: I took the Liberal side. On Apr. 30th there was a letter of mine in the Cambridge newspaper.—On Apr. 14th I began lectures, and finished on May 20th: there were 87 names.—My 'Gravitation' was either finished or so nearly finished that on Jan. 24th I had some conversation with Knight the publisher about printing it. It was printed in the spring, and on Apr. 27th Sheepshanks sent a copy of it to Lord Brougham. I received from Knight L83. 17s. 1d. for this Paper.—On May 10th I went to London, I believe to attend one of the Soirees which the Duke of Sussex gave as President of the Royal Society. The Duke invited me to breakfast privately with him the next morning. He then spoke to me, on the part of the Government, about my taking the office of Astronomer Royal. On May 19th I wrote him a semi-official letter, to which reference was made in subsequent correspondence on that subject.

"On May 12th my son Arthur was born.—In June the Observatory Syndicate made a satisfied Report.—On June 7th I went to the Greenwich Visitation, and again on June 14th I went to London, I believe for the purpose of trying the mounting of South's telescope, as it had been strengthened by Mr Simms by Sheepshanks's suggestions. I was subsequently in correspondence with Sheepshanks on the subject of the Arbitration on South's telescope, and my giving evidence on it. On July 29th, as I was shortly going away, I wrote him a Report on the Telescope, to be used in case of my absence. The award, which was given in December, was entirely in favour of Simms.—On July 23rd I went out, I think to my brother's marriage at Ixworth in Suffolk.—On Aug. 1st I started for Edensor and Cumberland, with my wife, sister, and three children: Georgiana Smith joined us at Edensor. We went by Otley, Harrogate, Ripon, and Stanmoor to Keswick, from whence we made many excursions. On Aug. 11th I went with Whewell to the clouds on Skiddaw, to try hygrometers. Mr Baily called on his way to the British Association at Edinburgh. On Sept. 10th we transferred our quarters to Ambleside, and after various excursions we returned to Edensor by Skipton and Bolton. On Sept. 19th I went to Doncaster and Finningley Park to see Mr Beaumont's Observatory. On Sept. 25th we posted in one day from Edensor to Cambridge.

"On Aug. 25th Mr Spring Rice (Lord Monteagle) wrote to me to enquire whether I would accept the office of Astronomer Royal if it were vacant. I replied (from Keswick) on Aug. 30th, expressing my general willingness, stipulating for my freedom of vote, &c., and referring to my letter to the Duke of Sussex. On Oct. 8th Lord Auckland, First Lord of the Admiralty, wrote: and on Oct. 10th I provisionally accepted the office. On Oct. 30th I wrote to ask for leave to give a course of lectures at Cambridge in case that my successor at Cambridge should find difficulty in doing it in the first year: and to this Lord Auckland assented on Oct. 31st. All this arrangement was for a time upset by the change of Ministry which shortly followed.

"Amongst miscellaneous matters, in March I had some correspondence with the Duke of Northumberland about the Cauchaix Telescope. In August I had to announce to him that the flint-lens had been a little shattered in Cauchaix's shop and required regrinding: finally on Dec. 17th I announced its arrival at Cambridge.—In the Planetary Reductions, I find that I employed one computer (Glaisher) for 34 weeks.—In November the Lalande Medal was awarded to me by the French Institut, and Mr Pentland conveyed it to me in December.—On March 14th I gave the Cambridge Philosophical Society a Paper, 'Continuation of researches into the value of Jupiter's Mass.' On Apr. 14th, 'On the Latitude of Cambridge Observatory.' On June 13th, 'On the position of the Ecliptic,' and 'On the Solar Eclipse of 1833,' to the Royal Astronomical Society. On Nov. 24th, 'On Computing the Diffraction of an Object Glass,' to the Cambridge Society. And on Dec. 3rd, 'On the Calculation of Perturbations,' to the Nautical Almanac: this Paper was written at Keswick between Aug. 22nd and 29th.—I also furnished Mr Sheepshanks with investigations regarding the form of the pivots of the Cape Circle."

1835

"On Jan. 9th 1835 I was elected correspondent of the French Academy; and on Jan. 26th Mr Pentland sent me L12. 6s., the balance of the proceeds of the Lalande Medal Fund.—I prepared my Paper for Smith's Prizes, and joined in the Examination as usual.

"There had been a very sudden change of Administration, and Sir R. Peel was now Prime Minister as First Lord of the Treasury, and Lord Lyndhurst was Lord Chancellor. On Jan. 19th I wrote to Lord Lyndhurst, asking him for a Suffolk living for my brother William, which he declined to give, though he remembered my application some years later. Whether my application led to the favour which I shortly received from the Government, I do not know. But, in dining with the Duke of Sussex in the last year, I had been introduced to Sir R. Peel, and he had conversed with me a long time, and appeared to have heard favourably of me. On Feb. 17th he wrote to me an autograph letter offering a pension of L300 per annum, with no terms of any kind, and allowing it to be settled if I should think fit on my wife. I wrote on Feb. 18th accepting it for my wife. In a few days the matter went through the formal steps, and Mr Whewell and Mr Sheepshanks were nominated trustees for my wife. The subject came before Parliament, by the Whig Party vindicating their own propriety in having offered me the office of Astronomer Royal in the preceding year; and Spring Rice's letter then written to me was published in the Times, &c."

* * * * *

The correspondence relating to the pension above-mentioned is given below, and appears to be of interest, both as conveying in very felicitous terms the opinion of a very eminent statesman on the general subject of such pensions, and as a most convincing proof of the lofty position in Science which the subject of this Memoir had then attained.

WHITEHALL GARDENS, Feb. 17 1835.

SIR,

You probably are aware that in a Resolution voted by the House of Commons in the last Session of Parliament, an opinion was expressed, that Pensions on the Civil List, ought not thereafter to be granted by the Crown excepting for the satisfaction of certain public claims, among which those resting on Scientific or Literary Eminence were especially mentioned.

I trust that no such Resolution would have been necessary to induce me as Minister of the Crown fully to recognize the justice of such claims, but I refer to the Resolution, as removing every impediment to a Communication of the nature of that which I am about to make to you.

In acting upon the Principle of the Resolution in so far as the Claims of Science are concerned, my first address is made to you, and made directly, and without previous communication with any other person, because it is dictated exclusively by public considerations, and because there can be no advantage in or any motive for indirect communication.

I consider you to have the first claim on the Royal Favour which Eminence in those high Pursuits to which your life is devoted, can give, and I fear that the Emoluments attached to your appointment in the University of Cambridge are hardly sufficient to relieve you from anxiety as to the Future on account of those in whose welfare you are deeply interested.

The state of the Civil List would enable me to advise the King to grant a pension of three hundred pounds per annum, and if the offer be acceptable to you the Pension shall be granted either to Mrs Airy or yourself as you may prefer.

I beg you distinctly to understand that your acquiescence in this Proposal, will impose upon you no obligation personal or political in the slightest degree. I make it solely upon public grounds, and I ask you, by the acceptance of it, to permit the King to give some slight encouragement to Science, by proving to those who may be disposed to follow your bright Example, that Devotion to the highest Branches of Mathematical and Astronomical Knowledge shall not necessarily involve them in constant solicitude as to the future condition of those, for whom the application of the same Talents to more lucrative Pursuits would have ensured an ample Provision.

I have the honor to be, Sir, With true Respect and Esteem, Your faithful Servant, ROBERT PEEL.

Mr Professor Airy, &c., &c., Cambridge.

OBSERVATORY, CAMBRIDGE, 1835, Feb. 18.

SIR,

I have the honor to acknowledge your letter of the 17th acquainting me with your intention of advising the King to grant a pension of L300 per annum from the Civil List to me or Mrs Airy.

I trust you will believe that I am sensible of the flattering terms in which this offer is made, and deeply grateful for the considerate manner in which the principal arrangement is left to my choice, as well as for the freedom from engagement in which your offer leaves me. I beg to state that I most willingly accept the offer. I should prefer that the pension be settled on Mrs Airy (by which I understand that in case of her surviving me the pension would be continued to her during her life, or in the contrary event would cease with her life).

I wish that I may have the good fortune to prove to the world that I do not accept this offer without an implied engagement on my part. I beg leave again to thank you for your attention, and to assure you that the form in which it is conveyed makes it doubly acceptable.

With sincere respect I have the honor to be, Sir, Your very faithful Servant, G.B. AIRY.

The Right Hon. Sir Robert Peel, Bart., First Lord of the Treasury, &c., &c.

WHITEHALL, Feb. 19th 1835.

SIR,

I will give immediate directions for the preparation of the Warrant settling the Pension on Mrs Airy—the effect of which will be, as you suppose, to grant the Pension to her for her life. I assure you I never gave an official order, which was accompanied with more satisfaction to myself than this.

I have the honor to be, Sir. Your faithful Servant, ROBERT PEEL.

Mr Professor Airy, &c., &c., Cambridge.

* * * * *

"On March 18th 1835 I started (meeting Sheepshanks at Kingstown) for Ireland. We visited Dublin Observatory, and then went direct to Markree near Sligo, to see Mr Cooper's telescope (our principal object). We passed on our return by Enniskillen and Ballyjamesduff, where my former pupil P. Morton was living, and returned on Apr. 3rd.—On Apr. 20th I was elected to the Royal Society, Edinburgh.—Apr. 22nd my wife wrote me from Edensor that her sister Florence was very ill: she died shortly after.—On May 4th I began lectures and finished on May 29th: there were 58 names.—My former pupil Guest asks my interest for the Recordership of Birmingham.—In June was circulated the Syndicate Report on the Observatory.—The date of the Preface to the 1834 Observations is June 16th.

"The Ministry had been again changed in the spring, and the Whigs were again in power. On June 11th Lord Auckland, who was again First Lord of the Admiralty (as last year), again wrote to me to offer me the office of Astronomer Royal, or to request my suggestions on the filling up of the office. On June 15th I wrote my first reply, and on June 17th wrote to accept it. On June 18th Lord Auckland acknowledges, and on June 22nd the King approved. Lord Auckland appointed to see me on Friday, June 23rd, but I was unwell. I had various correspondence with Lord Auckland, principally about buildings, and had an appointment with him for August 13th. As Lord Auckland was just quitting office, to go to India, I was introduced to Mr Charles Wood, the Secretary of the Admiralty, with whom principally the subsequent business was transacted. At this meeting Lord Auckland and Mr Wood expressed their feeling, that the Observatory had fallen into such a state of disrepute that the whole establishment ought to be cleared out. I represented that I could make it efficient with a good First Assistant; and the other Assistants were kept. But the establishment was in a queer state. The Royal Warrant under the Sign Manual was sent on August 11th. It was understood that my occupation of office would commence on October 1st, but repairs and alterations of buildings would make it impossible for me to reside at Greenwich before the end of the year. On Oct. 1st I went to the Observatory, and entered formally upon the office (though not residing for some time). Oct 7th is the date of my Official Instructions.

"I had made it a condition of accepting the office that the then First Assistant should be removed, and accordingly I had the charge of seeking another. I determined to have a man who had taken a respectable Cambridge degree. I made enquiry first of Mr Bowstead (brother to the bishop) and Mr Steventon: at length, consulting Mr Hopkins (a well-known private tutor at Cambridge), he recommended to me Mr Robert Main, of Queens' College, with whom I corresponded in the month (principally) of August, and whom on August 30th I nominated to the Admiralty. On Oct. 21st F.W. Simms, one of the Assistants (who apparently had hoped for the office of First Assistant, for which he was quite incompetent) resigned; and on Dec. 4th I appointed in his place Mr James Glaisher, who had been at Cambridge from the beginning of 1833, and on Dec. 10th the Admiralty approved.

"During this quarter of a year I was residing at Cambridge Observatory, visiting Greenwich once a week (at least for some time), the immediate superintendence of the Observatory being placed with Mr Main. I was however engaged in reforming the system of the Greenwich Observatory, and prepared and printed 30 skeleton forms for reductions of observations and other business. On Dec. 14th I resigned my Professorship to the Vice-Chancellor. But I continued the reduction of the observations, so that not a single figure was left to my successor: the last observations were those of Halley's Comet. The Preface to my 1835 Cambridge Observations is dated Aug. 22nd, 1836.

"In regard to the Northumberland Telescope, I had for some time been speculating on plans of mounting and enclosing the instrument, and had corresponded with Simms, A. Biddell, Cubitt, and others on the subject. On Apr. 24th Tulley the younger was endeavouring to adjust the object-glass. On May 31st I plainly asked the Duke of Northumberland whether he would defray the expense of the mounting and building. On June 4th he assented, and money was placed at a banker's to my order. I then proceeded in earnest: in the autumn the building was erected, and the dome was covered before the depth of winter. I continued in 1836 to superintend the mounting of the instrument.

"In regard to the Planetary Reductions: to July 11th J. Glaisher had been employed 27 weeks, and from July 11th to Jan. 16th, 1836, 25 weeks. Mr Spring Rice, when Chancellor of the Exchequer, had promised money, but no official minute had been made, and no money had been granted. On Aug. 21st I applied to Mr Baring (Secretary of the Treasury). After another letter he answered on Oct. 15th that he found no official minute. After writing to Vernon Harcourt and to Spring Rice, the matter was arranged: my outlay was refunded, and another sum granted.—In regard to Groombridge's Observations, I find that on Dec. 16th certain trial reductions had been made under my direction by J. Glaisher.—I had attempted some optical experiments in the summer, especially on the polarization of sky-light; but had been too busy with the Observatory to continue them.

"In August my wife was in a critical state of health.—In December I received information regarding merchant ships' chronometers, for which I had applied to Mr Charles Parker of Liverpool.—On Dec. 8th Mr Spring Rice and Lord John Russell offered me knighthood, but I declined it.—On July 23rd I went into Suffolk with my wife's sisters Elizabeth and Georgiana, and returned on August 3rd: this was all the holiday that I got in this year.—On the 14th of August I saw Mr Taylor, the Admiralty Civil Architect in London, and the extension of buildings at Greenwich Observatory was arranged.—I made various journeys to Greenwich, and on Dec. 17th, having sent off our furniture, we all quitted the Cambridge Observatory, and stayed for some days at the house of Miss Sheepshanks.

"Thus ended a busy and anxious year."

* * * * *

With reference to the offer of knighthood above-mentioned, Airy's reply is characteristic, and the short correspondence relating to it is therefore inserted.—The offer itself is an additional proof of the high estimation in which he stood at this time.

DOWNING STREET, Dec. 8th 1835.

MY DEAR SIR,

I have been in communication with my colleague Lord John Russell which has made me feel rather anxious to have the pleasure of seeing you, but on second thoughts it has occurred to me that the subject of my communication would render it more satisfactory to you to receive a letter than to pay a visit.

In testimony of the respect which is felt for your character and acquirements, there would be every disposition to recommend you to His Majesty to receive the distinction of Knighthood. I am quite aware that to you individually this may be a matter of small concern, but to the scientific world in general it will not be indifferent, and to foreign countries it will mark the consideration felt for you personally as well as for the position which you occupy among your learned contemporaries.

From a knowledge of the respect and esteem which I feel for you Lord John Russell has wished that the communication should be made through me rather than through any person who had not the pleasure of your acquaintance.

Pray let me hear from you and believe me my dear Sir, with compliments to Mrs Airy,

Very truly yours, T. SPRING RICE.

P.S.—It may be right to add that when a title of honor is conferred on grounds like those which apply to your case, no fees or charges of any kind would be payable.

OBSERVATORY, CAMBRIDGE, 1835, Dec. 10th.

MY DEAR SIR,

I beg to acknowledge your letter of the 8th, which I have received at this place, conveying to me an intimation of the wish of His Majesty's Ministers to recommend me to the King for the honor of Knighthood.

I beg to assure you that I am most sensible to the liberality which I have experienced from the Government in other as well as in pecuniary matters, and that I am very highly gratified by the consideration (undeserved by me, I fear) which they have displayed in the present instance. And if I now request permission to decline the honor offered to me, I trust I may make it fully understood that it is not because I value it lightly or because I am not anxious to receive honors from such a source.

The unalterable custom of this country has attached a certain degree of light consideration to titles of honor which are not supported by considerable fortune; or at least, it calls for the display of such an establishment as may not be conveniently supported by even a comfortable income. The provision attached to my official situation, and the liberality of the King towards one of the members of my family, have placed me in a position of great comfort. These circumstances however have bound me to consider myself as the devoted servant of the country, and to debar myself from efforts to increase my fortune which might otherwise have been open to me. I do not look forward therefore to any material increase of income, and that which I enjoy at present is hardly sufficient, in my opinion, to support respectably the honor which you and Lord John Russell have proposed to confer upon me. For this reason only I beg leave most respectfully to decline the honor of Knighthood at the present time.

I have only to add that my services will always be at the command of the Government in any scientific subject in which I can be of the smallest use.

I am, my dear Sir, Your very faithful Servant, G.B. AIRY.

The Right Honorable T. Spring Rice.

* * * * *

"In brief revision of the years from 1827 to 1835 I may confine myself to the two principal subjects—my Professorial Lectures, and my Conduct of the Cambridge Observatory.

"The Lectures as begun in 1827 included ordinary Mechanics, ordinary Hydrostatics and Pneumatics (I think that I did not touch, or touched very lightly, on the subjects connected with the Hydraulic Ram), and ordinary Optics (with a very few words on Polarization and Depolarization). In 1828 the two first were generally improved, and for the third (Optics) I introduced a few words on Circular Polarization. I believe that it was in 1829 that I made an addition to the Syllabus with a small engraving, shewing the interference of light in the best practical experiment (that of the flat prism); and I went thoroughly into the main points of the Undulatory Theory, interference, diffraction, &c. In 1830 I believe I went (in addition to what is mentioned above) into Polarization and Depolarization of all kinds. My best lecture diagrams were drawn and painted by my wife. The Lectures were universally pronounced to be valuable. The subjects underwent no material change in 1831, 2, 3, 4, 5; and I believe it was a matter of sincere regret to many persons that my removal to Greenwich terminated the series. Each lecture nominally occupied an hour. But I always encouraged students to stop and talk with me; and this supplement was usually considered a valuable part of the lecture. Practically the lecture, on most days, occupied two hours. I enjoyed the Lectures much: yet I felt that the labour (in addition to other work) made an impression on my strength, and I became at length desirous of terminating them.

"The Observatory, when I took charge of it, had only one instrument—the Transit-Instrument The principles however which I laid down for my own direction were adapted to the expected complete equipment, Planets (totally neglected at Greenwich) were to be observed. Observations were to be reduced completely, and the reductions were to be exhibited in an orderly way: this was a novelty in Astronomy. I considered it so important that I actually proposed to omit in my publication the original observations, but was dissuaded by Herschel and others. I sometimes suspended, observations for a short time, in order to obtain leisure for; the reductions. I had at first no intention of correcting the places of the fundamental stars as settled at Greenwich. But I found myself compelled to do so, because they were not sufficiently accurate; and then I took the course of observing and reducing as an independent observer, without reference to any other observatory. I introduced the principle of not correcting instrumental errors, but measuring them and applying numerical corrections. I determined my longitude by chronometers, and my latitude by a repeating circle borrowed from Mr Sheepshanks, which I used so well that the result; was only half a second in error. The form of my reductions in the published volume for 1828 is rather irregular, but the matter is good: it soon attracted attention. In 1829 the process was much the same: I had an assistant, Mr Baldrey. In 1830 still the same, with the additions:—that I formally gave the corrections of relative right-ascension of fundamental stars (without alteration of equinox, which I had not the means of obtaining) to be used in the year 1831; and that I reduced completely the observed occultations (with a small error, subsequently corrected). In 1831 the system of correction of broken transits was improved: the errors of assumed R.A. of Fundamental Stars were exhibited: Mean Solar Time was obtained from Sidereal Time by time of Transit of [Symbol: Aries] (computed by myself): the method of computing occultations was improved. In 1832 the small Equatoreal was erected, and was soon employed in observations of the elongation of the 4th Satellite of Jupiter for determining the mass of Jupiter. The Mural Circle was erected at the end of the year, but not used. The calculation of R.A. of Fundamental Stars was made homogeneously with the others: separate results of all were included in ledgers: a star-catalogue was formed: all as to the present time (1871). With the Equatoreal the difference of N.P.D. of Mars and stars was observed.

"With the beginning of 1833 the Mural Circle was established at work, a second assistant (Mr Glaisher) was appointed, and the Observatory might be considered complete. I made experiments on the graduations of the Circle. I detected and was annoyed by the R—D. I determined the latitude. I exhibited the separate results for N.P.D. of stars in ledger, and their means in Catalogue. I investigated from my observations the place of equinox and the obliquity of the ecliptic. I made another series of observations of Jupiter's 4th Satellite, for the mass of Jupiter. I observed the solar eclipse with the Equatoreal, by a method then first introduced, which I have since used several times at Cambridge and Greenwich with excellent effect. The Moon and the Planets were usually observed till near two in the morning. Correction for defective illumination applied when necessary. The volume is very complete, the only deficiency being in the observation of Moon and Planets through the severe morning hours. In 1834 the only novelties are—examination of the graduations of the declination circle of the Equatoreal (excessively bad): observations of a spot on Jupiter for rotation, and of Mars and stars. In 1835 (including January 1836) there is a more complete examination of the Equatoreal graduations: parallax and refraction for Equatoreal observations: a spot on Jupiter: a series of observations on Jupiter's 4th Satellite for the mass of Jupiter: Mars and stars: Halley's Comet (the best series of observations which could be made in the season): and a short series of meteorological observations, on a plan suggested by Sir John Herschel then at the Cape of Good Hope.

"I cannot tell precisely in which year I introduced the following useful custom. Towards the end of each year I procured a pocket-book for the following year with a space for every day, and carefully examining all the sources of elements of observations, and determining the observations to be made every day, I inserted them in the pocket-book. This system gave wonderful steadiness to the plan of observations for the next year. The system has been maintained in great perfection at the Observatory of Greenwich. (The first of these pocket-books which Prof. Adams has found is that for 1833.) Printed skeleton forms were introduced for all calculations from 1828. In the Greenwich Observatory Library there is a collection, I believe complete, of printed papers commencing with my manifesto, and containing all Syndicate Reports except for 1833 (when perhaps there was none). It seems from these that my first written Report on Observations, &c., was on May 30th, 1834. The first Syndicate Report is on May 25th, 1829."

* * * * *

A few remarks on Airy's private life and friends during his residence at Cambridge Observatory may be here appropriately inserted.

Amid the laborious occupations recorded in the foregoing pages, his social life and surroundings appear to have been most pleasant and congenial. At that period there were in residence in Cambridge, and particularly at Trinity, a large number of very brilliant men. Airy was essentially a Cambridge man. He had come up poor and friendless: he had gained friends and fame at the University, and his whole work had been done there. From the frequent references in after times both by him and his wife to their life at Cambridge, it is clear that they had a very pleasant recollection of it, and that the social gatherings there were remarkably attractive. He has himself recorded that with Whewell and Sedgwick, and his accomplished sisters-in-law, who were frequently on long visits at the Observatory, they formed pretty nearly one family.

His friendship with Whewell was very close. Although Whewell was at times hasty, and rough-mannered, and even extremely rude, yet he was generous and large-minded, and thoroughly upright. [Footnote: The following passage occurs in a letter from Airy to his wife, dated 1845, Sept. 17th: "I am sorry that —— speaks in such terms of the 'Grand Master,' as she used to be so proud of him: it is only those who have well gone through the ordeal of quarrels with him and almost insults from him, like Sheepshanks and me, that thoroughly appreciate the good that is in him: I am sure he will never want a good word from me."] In power of mind, in pursuits, and interests, Airy had more in common with Whewell than with any other of his friends. It was with Whewell that he undertook the experiments at Dolcoath: it was to Whewell that he first communicated the result of his remarkable investigation of the Long Inequality of Venus and the Earth; and some of his Optical researches were conducted jointly with Whewell. Whewell took his degree in 1816, seven years before Airy, and his reputation, both for mathematical and all-round knowledge, was extremely and deservedly great, but he was always most generous in his recognition of Airy's powers. Thus in a letter of Mar. 16th, 1823 (Life of William Whewell by Mrs Stair Douglas), he says, "Airy is certainly a most extraordinary man, and deserves everything that can be said of him"; and again in the autumn of 1826 he writes to his aunt, "You mentioned a difficulty which had occurred to you in one of your late letters; how Airy should be made Professor while I was here, who, being your nephew, must of course, on that account, deserve it better than he could. Now it is a thing which you will think odd, but it is nevertheless true, that Airy is a better mathematician than your nephew, and has moreover been much more employed of late in such studies.... Seriously speaking, Airy is by very much the best person they could have chosen for the situation, and few things have given me so much pleasure as his election." How much Whewell depended upon his friends at the Observatory may be gathered from a letter which he wrote to his sister on Dec. 21st, 1833. "We have lately been in alarm here on the subject of illness. Two very near friends of mine, Prof. and Mrs Airy, have had the scarlet fever at the same time; she more slightly, he very severely. They are now, I am thankful to say, doing well and recovering rapidly. You will recollect that I was staying with them at her father's in Derbyshire in the summer. They are, I think, two of the most admirable and delightful persons that the world contains." And again on Dec. 20th, 1835, he wrote to his sister Ann, "My friends—I may almost say my dearest friends —Professor Airy and his family have left Cambridge, he being appointed Astronomer Royal at Greenwich—to me an irreparable loss; but I shall probably go and see how they look in their new abode." Their close intercourse was naturally interrupted by Airy's removal to Greenwich, but their friendly feelings and mutual respect continued without material break till Whewell's death. There was frequent correspondence between them, especially on matters connected with the conduct and teaching of the University, in which they both took a keen interest, and a warm welcome at Trinity Lodge always awaited Mr and Mrs Airy when they visited Cambridge. In a letter written to Mrs Stair Douglas on Feb. 11th, 1882, enclosing some of Whewell's letters, there occurs the following passage: "After the decease of Mrs Whewell, Whewell wrote to my wife a mournful letter, telling her of his melancholy state, and asking her to visit him at the Lodge for a few days. And she did go, and did the honours of the house for several days. You will gather from this the relation in which the families stood." Whewell died on Mar. 6th, 1866, from the effects of a fall from his horse, and the following extract is from a letter written by Airy to Whewell's niece, Mrs Sumner Gibson, on hearing of the death of his old friend:

"The Master was, I believe, my oldest surviving friend (beyond my own family), and, after an acquaintance of 46 years, I must have been one of his oldest friends. We have during that time been connected privately and officially: we travelled together and experimented together: and as opportunity served (but I need not say in very different degrees) we both laboured for our College and University. A terrible blank is left on my mind."

Sedgwick was probably 15 years older than Airy: he took his degree in 1808. But the astonishing buoyancy of spirits and bonhomie of Sedgwick fitted him for all ages alike. He was undoubtedly the most popular man in Cambridge in modern times. His ability, his brightness and wit, his fearless honesty and uprightness, his plain-speaking and good humour, rendered him a universal favourite. His close alliance with Airy was much more social than scientific. It is true that they made some geological excursions together, but, at any rate with Airy, it was far more by way of recreation than of serious study, and Sedgwick's science was entirely geological. Their friendship continued till Sedgwick's death, though it was once or twice imperilled by Sedgwick's impulsive and hasty nature.

Peacock took his degree in 1813 (Herschel's year), and was therefore probably 10 years older than Airy. He was the earliest and staunchest friend of Airy in his undergraduate years, encouraged him in every possible way, lent him books, assisted him in his studies, helped him with wise advice on many occasions, and took the greatest interest in his success. He was a good and advanced mathematician, and with a great deal of shrewdness and common-sense he united a singular kindness and gentleness of manner. It is therefore not to be wondered at that he was regarded by Airy with the greatest esteem and affection, and though they were afterwards separated, by Peacock becoming Dean of Ely and Airy Astronomer Royal, yet their warm friendship was never broken. The following letter, written by Airy to Mrs Peacock on receiving the news of the death of the Dean, well expresses his feelings towards his old friend:

TRINITY LODGE, CAMBRIDGE, 1858, Dec. 4.

MY DEAR MADAM,

I have desired for some time to express to you my sympathies on occasion of the sad bereavement which has come upon me perhaps as strongly as upon any one not connected by family ties with my late friend. But I can scarcely give you an idea how every disposable moment of my time has been occupied. I am now called to Cambridge on business, and I seize the first free time to write to you.

My late friend was the first person whom I knew in College (I had an introduction to him when I went up as freshman). From the first, he desired me to consider the introduction not as entitling me to a mere formal recognition from him, but as authorizing me at all times to call on him for any assistance which I might require. And this was fully carried out: I referred to him in every difficulty: I had the entire command of his rooms and library (a very important aid in following the new course of mathematics which he had been so instrumental in introducing into the University) in his occasional absences: and in all respects I looked to him as to a parent. All my debts to other friends in the University added together are not comparable to what I owe to the late Dean.

Latterly I need not say that I owed much to him and that I owe much to you for your kind notice of my two sons, even since the sad event which has put it out of his power to do more.

In the past summer, looking to my custom of making a visit to Cambridge in some part of the October Term, I had determined that a visit to Ely this year should not depend on the chance of being free to leave Cambridge, but that, if it should be found convenient to yourself and the Dean, the first journey should be made to Ely. I wish that I had formed the same resolution one or two years ago.

With many thanks for your kindness, and with deep sympathy on this occasion,

I am, My dear Madam, Yours very faithfully, G.B. AIRY.

Sheepshanks was a Fellow of Trinity, in orders: he was probably seven years older than Airy (he took his degree in 1816). He was not one of Airy's earliest friends, but he had a great taste and liking for astronomy, and the friendship between them when once established became very close. He was a very staunch and fearless friend, an able and incisive writer, and remarkably energetic and diligent in astronomical investigations. He, or his sister, Miss Sheepshanks, had a house in London, and Sheepshanks was very much in London, and busied himself extremely with the work of the Royal Observatory, that of the Board of Longitude, and miscellaneous astronomical matters. He was most hospitable to his friends, and while Airy resided at Cambridge his house was always open to receive him on his frequent visits to town. In the various polemical discussions on scientific matters in which Airy was engaged, Sheepshanks was an invaluable ally, and after Airy's removal to Greenwich had more or less separated him from his Cambridge friends, Sheepshanks was still associated with him and took a keen interest in his Greenwich work. And this continued till Sheepshanks's death. The warmest friendship always subsisted between the family at the Observatory and Mr and Miss Sheepshanks.

There were many other friends, able and talented men, but these four were the chief, and it is curious to note that they were all much older than Airy. It would seem as if Airy's knowledge had matured in so remarkable a manner, and the original work that he produced was so brilliant and copious, that by common consent he ranked with men who were much his seniors: and the natural gravity and decorum of his manners when quite a young man well supported the idea of an age considerably greater than was actually the case.



CHAPTER V.

AT GREENWICH OBSERVATORY—1836 TO 1846.

1836

"Through the last quarter of 1835 I had kept everything going on at the Greenwich Observatory in the same manner in which Mr Pond had carried it on. With the beginning of 1836 my new system began. I had already prepared 30 printed skeleton forms (a system totally unknown to Mr Pond) which were now brought into use. And, having seen the utility of the Copying Press in merchants' offices, I procured one. From this time my correspondence, public and private, is exceedingly perfect.

"At this time the dwelling house was still unconnected with the Observatory. It had no staircase to the Octagon Room. Four new rooms had been built for me on the western side of the dwelling house, but they were not yet habitable. The North-east Dome ground floor was still a passage room. The North Terrace was the official passage to the North-west Dome, where there was a miserable Equatoreal, and to the 25-foot Zenith Tube (in a square tower like a steeple, which connected the N.W. Dome with Flamsteed's house). The southern boundary of the garden ran down a hollow which divides the peninsula from the site of the present Magnetic Observatory, in such a manner that the principal part of the garden was fully exposed to the public. The Computing Room was a most pitiful little room. There was so little room for me that I transported the principal table to a room in my house, where I conducted much of my own official business. A large useless reflecting telescope (Ramage's), on the plan and nearly of the size of Sir W. Herschel's principal telescope, encumbered the centre of the Front Court.

"On Jan. 11th I addressed Mr Buck, agent of the Princess Sophia of Gloucester, Ranger of Greenwich Park, for leave to enclose a portion of the ground overlooking my garden. This was soon granted, and I was partially delivered from the inconvenience of the public gaze. The liberation was not complete till the Magnetic ground was enclosed in 1837.

"In the inferior departments of the Admiralty, especially in the Hydrographic Office (then represented by Captain Beaufort) with which I was principally connected, the Observatory was considered rather as a place for managing Government chronometers than as a place of science. The preceding First Assistant (Taylor) had kept a book of letter references, and I found that out of 840 letters, 820 related to Government chronometers only. On Jan. 17th I mentally sketched my regulations for my own share in chronometer business. I had some correspondence with Captain Beaufort, but we could not agree, and the matter was referred to the Admiralty. Finally arrangements were made which put the chronometer business in proper subordination to the scientific charge of the Observatory.

"In my first negociations with the Admiralty referring to acceptance of the office of Astronomer Royal, in 1834, Lord Auckland being then First Lord of the Admiralty, I had stipulated that, as my successor at Cambridge would be unprepared to carry on my Lectures, I should have permission to give a final course of Lectures there. At the end of 1835 Lord Auckland was succeeded by Lord Minto: I claimed the permission from him and he refused it. When this was known in Cambridge a petition was presented by many Cambridge residents, and Lord Minto yielded. On April 18th I went to Cambridge with my wife, residing at the Bull Inn, and began Lectures on April 21st: they continued (apparently) to May 27th. My lecture-room was crowded (the number of names was 110) and the lectures gave great satisfaction. I offered to the Admiralty to put all the profits in their hands, and transmitted a cheque to the Accountant General of the Navy: but the Admiralty declined to receive them.

"On June 4th the Annual Visitation of the Observatory was held, Mr F. Baily in the Chair. I presented a written Report on the Observatory (a custom which I had introduced at Cambridge) in which I did not suppress the expression of my feelings about chronometer business. The Hydrographer, Captain Beaufort, who was one of the Official Visitors, was irritated: and by his influence the Report was not printed. I kept it and succeeding Reports safe for three years, and then the Board of Visitors agreed to print them; and four Reports were printed together, and bound with the Greenwich Observations of 1838.

"In the course of this year I completed the volume of Observations made at Cambridge Observatory in 1835 and on Nov. 10th the printed copies were distributed. About the end of 1835 the Dome for the Northumberland Telescope was erected: but apparently the polar frame was not erected."

The following account of an accident which occurred during the construction of the dome is extracted from a letter by Airy to his wife dated 1836 Jan. 31st. "The workmen's account of the dome blowing off is very curious: it must have been a strange gust. It started suddenly when the men were all inside and Beaumont was looking up at it: the cannon balls were thrown in with great violence (one of them going between the spokes of Ransomes' large casting), and instantly after the dome had started, the boards of the outside scaffolding which had been tossed up by the same gust dropped down into the gap which the dome had left. It is a wonder that none of the men were hurt and that the iron was not broken. The dome is quite covered and I think does not look so well as when the hooping was visible."

"Previous to 1836 I had begun to contemplate the attachment of Magnetic Observations to the Observatory, and had corresponded with Prof. Christie, Prof. Lloyd, Prof. J. D. Forbes, and Mr Gauss on the subject. On Jan. 12th 1836 I addressed a formal letter to the Admiralty, and on Jan. 18th received their answer that they had referred it to the Board of Visitors. On March 25th I received authority for the expenditure of L30, and I believe that I then ordered Merz's 2-foot magnet. The Visitors met on Feb. 26th and after some discussion the site was chosen and the extent of ground generally defined, and on Dec. 22nd Mr Spring Rice (Lord Monteagle) as Chancellor of the Exchequer virtually effected the transfer of the ground. But no further steps were taken in 1836. A letter on a systematic course of magnetic observations in various parts of the world was addressed by Baron Alexander Humboldt to the Duke of Sussex, President of the Royal Society; and was referred to Prof. Christie and me. We reported on it on June 9th 1836, strongly recommending the adoption of the scheme.

"A plan had been proposed by the Promoters of the London and Gravesend Railway (Col. Landman, Engineer) for carrying a railway at high level across the bottom of the Park. On Jan. 9th I received orders from the Admiralty to examine into its possible effect in producing vibrations in the Observatory. After much correspondence, examination of ground, &c., I fixed upon a part of the Greenwich Railway (not yet opened for traffic) near the place where the Croydon trunk line now joins it, as the place for trains to run upon, while I made observations with a telescope viewing a collimator by reflection in mercury at the distance of 500 feet. The experiments were made on Jan. 25th, and I reported on Feb. 4th. It was shewn that there would be some danger to the Observatory. On Nov. 2nd Mr James Walker, Engineer, brought a model of a railway to pass by tunnel under the lower part of the Park: apparently this scheme was not pressed.

"In addition to the routine work of the Observatory, a special set of observations were made to determine the mass of Jupiter.—Also the Solar Eclipse of May 15th was observed at Greenwich in the manner which I had introduced at Cambridge.—The Ordnance Zenith Sector, and the instruments for the St Helena Observatory were brought for examination.—Much attention was given to chronometers, and various steps were taken for their improvement.—I had some important correspondence with Mr (Sir John) Lubbock, upon the Lunar Theory generally and his proposed empirical lunar tables. This was the first germ of the great reduction of Lunar Observations which I subsequently carried out.—In October I was nominated on the Council of the Royal Society, having been admitted a Fellow on Feb. 18th 1836. I was President of the Astronomical Society during this and the preceding year (1836 and 1835).

"My connection with Groombridge's Catalogue of Stars began in 1832, and the examination, in concert with Mr Baily, of the edition printed by Mr Henry Taylor, resulted in its condemnation. In 1834 I volunteered to the Admiralty to prepare a new edition, and received their thanks and their authority for proceeding. It required a great deal of examination of details, and much time was spent on it in 1836: but it was not brought to the state of readiness for press.

"My predecessor, Mr Pond, died on Sept. 7th 1836, and was interred in Halley's tomb in Lee churchyard."

* * * * *

The following letter was written by Airy in support of the application for a pension to Mrs Pond, who had been left in great distress:

To HENRY WARBURTON, ESQ.

"The points upon which in my opinion Mr Pond's claims to the gratitude of Astronomers are founded, are principally the following. First and chief, the accuracy which he introduced into all the principal observations. This is a thing which from its nature it is extremely difficult to estimate now, so long after the change has been made, and I can only say that so far as I can ascertain from books the change is one of very great extent: for certainty and accuracy, Astronomy is quite a different thing from what it was, and this is mainly due to Mr Pond. The most striking exemplification of this is in his laborious working out of every conceivable cause or indication of error in the Circle and the two Circles: but very great praise is also due for the new system which he introduced in working the Transit. In comparing Mr Pond's systems of observation with Dr Maskelyne's, no one can avoid being impressed with the inferiority of Dr Maskelyne's. It is very important to notice that the continental observatories which have since attracted so much attention did not at that time exist or did not exist in vigour. Secondly, the attention bestowed by Mr Pond on those points (chiefly of sidereal astronomy) which he regarded as fundamental: to which such masses of observations were directed as entirely to remove the doubts from probable error of individual observations or chance circumstances which have injured many other determinations. Thirdly, the regularity of observation. The effect of all these has been that, since the commencement of Mr Pond's residence at Greenwich, Astronomy considered as an accurate representation of the state of the heavens in the most material points has acquired a certainty and an extent which it never had before. There is no period in the history of the science so clean. On some matters (in regard to the choice of observations) I might say that my own judgment would have differed in some degree from Mr Pond's, but one thing could have been gained only by giving up another, and upon the general accuracy no improvement could have been made. Mr Pond understood nothing of physical astronomy; but neither did anybody else, in England.

"The supposed decrease of general efficiency in the last few years is to be ascribed to the following causes:

1. Mr Pond's ill health.

2. The inefficiency of his first assistant.

3. The oppression of business connected with chronometers.

"The last of these, as I have reason to think, operated very far. Business of this nature which (necessarily) is daily and peremptory will always prevail over that which is general and confidential. I will not trouble you with an account of the various ways in which the chronometer business teazed the Astronomer Royal (several alterations having been made at my representation), but shall merely remark that much of the business had no connection whatever with astronomy.

"I beg to submit these remarks to your perusal, requesting you to point out to me what part of them should be laid before any of the King's Ministers, at what time, in what shape, and to whom addressed. I am quite sure that Mrs Pond's claims require nothing to ensure favourable consideration but the impression of such a feeling of Mr Pond's astronomical merits as must be entertained by any reasonable astronomer; and I am most anxious to assist in conveying this impression.

"Of private history: I went to Suffolk for a week on Mar. 25th. On Sept. 19th my son Wilfrid (my fourth child) was born. In October I made an excursion for a week round the coast of Kent. In November I went to my brother's house at Keysoe in Bedfordshire: I was much exposed to cold on the return-journey, which probably aggravated the illness that soon followed. From Nov. 27th I was ill; made the last journal entry of the year on Dec. 6th; the next was on Jan. 14th, 1837. I find that in this year I had introduced Arthur Biddell to the Tithe Commutation Office, where he was soon favourably received, and from which connection he obtained very profitable employment as a valuer."

1837

"My connection with Cambridge Observatory was not yet finished. I had determined that I would not leave a figure to be computed by my successor. In October I had (at my private expense) set Mr Glaisher to work on reducing the observations of Sun, Moon, and Planets made in 1833, 1834, 1835; and subsequently had the calculations examined by Mr Hartnup. This employed me at times through 1837. I state here, once for all, that every calculation or other work in reference to the Cambridge Observatory, in this and subsequent years, was done at my private expense. The work of the Northumberland Telescope was going on through the year: from Nov. 24th to 29th I was at Cambridge on these works.

"An object-glass of 6-3/4 inches aperture (a most unusual size at this time, when it was difficult to find a 4-inch or 5-inch glass) had been presented to the Greenwich Observatory by my friend Mr Sheepshanks, and on Mar. 29th I received from the Admiralty authority for mounting it equatoreally in the empty South Dome, which had been intended for a copy of the Palermo Circle.—In the month of July the Admiralty wished for my political assistance in a Greenwich election, but I refused to give any.—On Jan. 3rd I gave notice to the Admiralty that I had finished the computations of Groombridge's Catalogue, and was ready to print. The printing was authorized and proceeded (the introduction was finished on Nov. 22nd), but the book was not quite ready till the beginning of 1838.—In connection with the Cavendish experiment: on June 10th I wrote to Spring Rice (Chancellor of the Exchequer) for L500, which was soon granted: and from this time there is a great deal of correspondence (mainly with Mr Baily) upon the details of the experiment and the theory of the calculation.—On July 24th I saw the descent of the parachute by which Mr Cocking was killed. I attended the coroner's inquest and gave evidence a few days later.

"The Planetary Reductions from 1750 to 1830 had been going on: the computers (Glaisher, Hartnup, and Thomas) worked in the Octagon Room, and considerable advance was made.—In consequence of the agitation of the proposal by Mr Lubbock to form empirical tables of the Moon, for which I proposed to substitute complete reduction of the observations of the Moon from 1750, the British Association at York (Oct. 23rd, 1837) appointed a deputation (including myself) to place the matter before the Government. I wrote on the matter to Mr Wood (Lord Halifax) stating that it would be proper to raise the First Assistant's salary, and to give me more indefinite power about employing computers. In all these things I received cordial assistance from Mr Wood. The Chancellor of the Exchequer (Mr Spring Rice) received us on Dec. 20th: statements were furnished by me, and the business was sanctioned immediately.—During this year I was very much engaged in correspondence with Lubbock and others on improvements of the Lunar Theory.