Autobiography of Sir George Biddell Airy Part 12

ST PeTERSBOURG,

_ce_ 24 _Aout_, 1847 ---------- 5 _Septbr._ _a Mr G. B. Airy, Esq., Astronome Royal de S. M. Britannique a Greenwich_.

Airy provisionally accepted the Order, but wrote at once to Lord John Russell the following letter of enquiry:

ROYAL OBSERVATORY, GREENWICH, _1847, Oct. 15_.

MY LORD,

In respect of the office of Astronomer Royal, I refer to the first Lord of the Treasury as Official Patron. In virtue of this relation I have the honour to lay before your Lordship the following statement, and to solicit your instructions thereon.

For conducting with efficiency and with credit to the nation the inst.i.tution which is entrusted to me, I have judged it proper to cultivate intimate relations with the princ.i.p.al Observatories of Europe, and in particular with the great Observatory founded by the Emperor of Russia at Pulkowa near St Petersburg. I have several times received Mr Struve, the Director of that Observatory, at Greenwich: and in the past summer I made a journey to St Petersburg for the purpose of seeing the Observatory of Pulkowa.

Since my return from Russia, I have received a communication from Count Ouvaroff, Minister of Public Instruction in the Russian Empire, informing me that the Emperor of Russia desires to confer on me the decoration of Knight Commander in the second rank of the Order of St Stanislas.

And I have the honour now to enquire of your Lordship whether it is permitted to me to accept from the Emperor of Russia this decoration.

I have the honour to be, My Lord, Your Lordship's very obedient servant, G.B. AIRY.

_The Rt Honble Lord John Russell, &c. &c. &c.

First Lord of the Treasury_.

The answer was as follows:

DOWNING STREET, _October 19, 1847_.

SIR,

I am desired by Lord John Russell to acknowledge the receipt of your letter, of the 14th inst. and to transmit to you the enclosed paper respecting Foreign Orders by which you will perceive that it would be contrary to the regulations to grant you the permission you desire.

I am, Sir, Your obedient servant, C.A. GREY.

_G. B. Airy, Esq_.

The pa.s.sage in the Regulations referred to above is quoted in the following letter to Count Ouvaroff:

ROYAL OBSERVATORY, GREENWICH, _1847, Oct. 22_.

SIR,

Referring to your Excellency's letter of the 24 August/5 September, and to my answer of the 25th September, in which I expressed my sense of the high honor conferred on me by His Majesty the Emperor of Russia in offering me, through your Excellency, the Order of St Stanislas, and my pride in accepting it:--I beg leave further to acquaint you that I have thought it necessary to make enquiry of Lord John Russell, First Lord of Her Majesty's Treasury, as to my competency to accept this decoration from His Majesty the Emperor of Russia: and that his Lordship in reply has referred me to the following Regulation of the British Court;

"5th. That no Subject of Her Majesty could be allowed to accept the Insignia of a Foreign Order from any Sovereign of a Foreign State, except they shall be so conferred in consequence of active and distinguished services before the Enemy, either at Sea, or in the Field; or unless he shall have been actually employed in the Service of the Foreign Sovereign."

In consequence of the stringency of this Regulation, it is my duty now to state to your Excellency that I am unable to accept the decoration which His Majesty the Emperor of Russia was pleased, through your Excellency, to offer to me.

I beg leave to repeat the expression of my profound reverence to His Majesty and of my deep sense of the honor which he has done me.

I have the honor to be, Sir, Your Excellency's very faithful and obedient servant, G.B. AIRY.

_To His Excellency Count Ouvaroff, &c. &c._

In the course of the following year a very handsome gold medal, specially struck, was transmitted by Count Ouvaroff on the part of the Emperor of Russia, to Mr Airy.

1848

"In April I received authority to purchase of Simms an 8-inch object-gla.s.s for the new Transit Circle for _300_. The gla.s.s was tested and found satisfactory. While at Playford in January I drew the first plans of the Transit Circle: and C. May sketched some parts. Definite plans were soon sent to Ransomes and May, and to Simms in March. The instrument and the building were proceeded with during the year. The New Transit Circle was to be erected in the Circle Room, and considerable arrangement was necessary for continuing the Circle Observations with the existing instruments, whilst the new instrument was under erection. When the new Transit is completely mounted, the old Transit Instrument may be removed, and the Transit Room will be free for any other purpose. I propose to take it as Private Room for the Astronomer Royal.--On May 12th I made my first proposal of the Reflex Zenith Tube. The principle of it is as follows: Let the micrometer be placed close to the object-gla.s.s, the frame of the micrometer being firmly connected with the object-gla.s.s cell, and a reflecting eye-piece being used with no material tube pa.s.sing over the object-gla.s.s: and let a basin of quicksilver be placed below the object-gla.s.s, but in no mechanical connection with it, at a distance equal to half the focal length of the object-gla.s.s. Such an instrument would at least be free from all uncertainties of twist of plumb-line, viscosity of water, attachment of upper plumb-line microscope, attachment of lower plumb-line microscope, and the observations connected with them: and might be expected, as a result of this extreme simplicity, to give accurate results.--A considerable error was discovered in the graduation of Troughton's Circle, amounting in one part to six seconds, which is referred to as follows: 'This instance has strongly confirmed me in an opinion which I have long held--that no independent division is comparable in general accuracy to engine-division,--where the fundamental divisions of the engine have been made by Troughton's method, and where in any case the determination by the astronomer of errors of a few divisions will suffice, in consequence of the uniformity of law of error, to give the errors of the intermediate divisions.'--The method of observing with the Altazimuth is carefully described, and the effect of it, in increasing the number of observations of the Moon, is thus given for the thirteen lunations between 1847, May 15, and 1848, May 30. 'Number of days of complete observations with the Meridional Instruments, 111; number of days of complete observations with Alt.i.tude and Azimuth Instrument, 203. The results of the observations appear very good; perhaps a little, and but a little, inferior to those of the Meridional Instruments. I consider that the object for which this instrument was erected is successfully attained.'--Being satisfied with the general efficiency of the system arranged by Mr Brooke for our photographic records (of magnetical observations) I wrote to the Admiralty in his favour, and on Aug. 25th the Admiralty ordered the payment of _500_ to him. A Committee of the Royal Society also recommended a reward of _250_ to Mr Ronalds, which I believe was paid to him.--On May 1st the last revise of the Lunar Reductions was pa.s.sed, and on May 5th, 500 copies were sent for binding.--In this year Schumacher and I refused a medal to Miss Mitch.e.l.l for a Comet discovered, because the rules of correspondence had not been strictly followed: the King of Denmark gave one by special favour.--In this year occurred the discovery of Saturn's 8th Satellite by Mr La.s.sell: upon which I have various correspondence.--On the 18th of December the degree of LL.D. was conferred upon me by the University of Edinburgh.--The Ipswich Lectures: A wish had been expressed that I would give a series of Astronomical Lectures to the people of Ipswich. I therefore arranged with great care the necessary apparatus, and lectured six evenings in a room (I forget its name--it might be Temperance Hall--high above St Matthew's Street), from Mar. 13th to the end of the week. A shorthand writer took them down: and these formed the 'Ipswich Lectures,' which were afterwards published by the Ipswich Museum (for whose benefit the lectures were given) and by myself, in several editions, and afterwards by Messrs Macmillan in repeated editions under the t.i.tle of 'Airy's Popular Astronomy.'--It had been found necessary to include under one body all the unconnected Commissions of Sewers for the Metropolis, and Lord Morpeth requested me to be a member. Its operations began on Oct. 28th. In const.i.tution it was the most foolish that I ever knew: consisting of, I think, some 200 persons, who could not possibly attend to it. It came to an end in the next year."

Of private history: "I was at Playford from Jan. 1st to 11th, and again from Jan. 17th to 25th: also at Playford from June 21st to July 12th.--From Aug. 23rd to Sept. 12th I was in Ireland on a visit to Lord Rosse at Parsonstown, chiefly engaged on trials of his large telescope. I returned by Liverpool, where I inspected the Liverpool Equatoreal and Clockwork, and examined Mr La.s.sell's telescopes and grinding apparatus.--From Dec. 6th to 20th I was at Edinburgh with my wife, on a visit to Prof. J. D. Forbes. We made various excursions, and I attended lectures by Prof. Wilson and Sir W. Hamilton: on the 18th I gave a lecture in Prof. Forbes's room. I received the Honorary Degree of LL.D., and made a statement on the Telescopes of Lord Rosse and Mr La.s.sell to the Royal Society of Edinburgh. Returned to Greenwich by Brampton."

Here is a reminiscence of the "Ipswich Lectures," in a letter to his wife, dated Playford, 1848 Mar. 14, "At the proper time I went to the hall: found a chairman installed (Mr Western): was presented to him, and by him presented to the audience: made my bow and commenced. The room was quite full: I have rarely seen such a sea of faces; about 700 I believe. Everything went off extremely well, except that the rollers of the moving piece of sky would squeak: but people did not mind it: and when first a star pa.s.sed the meridian, then Jupiter, then some stars, and then Saturn, he was much applauded. Before beginning I gave notice that I should wait to answer questions: and as soon as the lecture was finished the Chairman repeated this and begged people to ask. So several people did ask very pertinent questions (from the benches) shewing that they had attended well. Others came up and asked questions."

The following extracts are from letters written to his wife while on his visit to Lord Rosse at Parsonstown in Ireland. On the way he stopped at Bangor and looked at the Tubular Bridge Works, which are thus referred to: "Stopped at Bangor, settled _pro tem_. at the Castle, and then walked past the Suspension Bridge towards the Tube Works, which are about 1-1/2 mile south-west of the Suspension Bridge.

The way was by a path through fields near the water side: and from one or two points in this, the appearance of the Suspension Bridge was most majestic. The Tube Bridge consists of four spans, two over water and two over sloping land. The parts for the double tube over the water spans (four lengths of tube) are building on a platform as at Conway, to be floated by barges as there: the parts over the sloping banks are to be built in their place, on an immense scaffolding. I suspect that, in regard to these parts, Stephenson is sacrificing a great deal of money to uniformity of plan: and that it would have been much cheaper to build out stone arches to the piers touching the water.... The Tube Works are evidently the grand promenade of the idlers about Bangor: I saw many scores of ladies and gentlemen walking that way with their baskets of provision, evidently going to gipsy in the fields close by."

THE CASTLE, PARSONSTOWN, _1848, Aug. 29_.

After tea it was voted that the night was likely to be fine, so we all turned out. The night was uncertain: sometimes entirely clouded, sometimes partially, but objects were pretty well seen when the sky was clear: the latter part was much steadier. From the interruption by clouds, the slowness of finding with and managing a large instrument (especially as their finding apparatus is not perfectly arranged) and the desire of looking well at an object when we had got it, we did not look at many objects. The princ.i.p.al were, Saturn and the Annular Nebula of Lyra with the 3-feet; Saturn, a remarkable cl.u.s.ter of stars, and a remarkable planetary nebula, with the 6-feet. With the large telescope, the evidence of the quant.i.ty of light is prodigious. And the light of an object is seen in the field without any colour or any spreading of stray light: and it is easy to see that the vision with a reflecting telescope may be much more perfect than with a refractor. With these large apertures, the rings round the stars are insensible. The planetary nebula looked a ma.s.s of living and intensely brilliant light: this is an object which I do not suppose can be seen at all in our ordinary telescopes. The definition of the stars near the zenith is extremely good: with a high power (as 800) they are points or very nearly so--indeed I believe quite so--so that it is clear that the whole light from the great 6-feet mirror is collected into a s.p.a.ce not bigger than the point of a needle. But in other positions of the telescope the definition is not good: and we must look to-day to see what is the cause of this fault. It is not a fault in the telescope, properly so-called, but it is either a tilt of the mirror, or an edge-pressure upon the mirror when the telescope points lower down which distorts its figure, or something of that kind. So I could not see Saturn at all well, for which I was sorry, as I could so well have compared his appearance with what I have seen before. I shall be very much pleased if we can make out what is the fault of adjustment, and so correct it as to get good images everywhere. It is evident that the figuring of the mirror, the polishing, and the general arrangement, are perfectly managed.

THE CASTLE, PARSONSTOWN, _1848, Aug. 30_.

Yesterday we were employed entirely about the Great Telescope, beginning rather late. The princ.i.p.al objects had relation to the fault of definition when the telescope is pointed low (which I had remarked on the preceding night), and were, to make ourselves acquainted with the mechanism of the mirror's mounting generally, and to measure in various ways whether the mirror actually does shift its place when the telescope is set to different angles of elevation. For the latter we found that the mirror actually does tilt 1/4 of an inch when the tube points low. This of itself will not account for the fault but it indicates that the lower part is held fast in a way that may cause a strain which would produce the fault. These operations and reasonings took a good deal of time. Lord Rosse is disposed to make an alteration in the mounting for the purpose of correcting this possible strain.

THE CASTLE, PARSONSTOWN, _1848, Aug. 31_.

The weather here is still vexatious: but not absolutely repulsive.

Yesterday morning Lord Rosse arranged a new method of suspending the great mirror, so as to take its edgewise pressure in a manner that allowed the springy supports of its flat back to act. This employed his workmen all day, so that the proposed finish of polishing the new mirror could not go on. I took one Camera Lucida sketch of the instrument in the morning, dodging the heavy showers as well as I could; then, as the afternoon was extremely fine, I took another, with my head almost roasted by the sun. This last view is extremely pretty and characteristic, embracing parts of the mounting not shewn well in the others, and also shewing the Castle, the Observatory, and the 3-feet telescope. The night promised exceedingly well: but when we got actually to the telescope it began to cloud and at length became hopeless. However I saw that the fault which I had remarked on the two preceding nights was gone. There is now a slight exhibition of another fault to a much smaller extent. We shall probably be looking at the telescope to-day in reference to it.

THE CASTLE, PARSONSTOWN, _1848, Sept. 1_.

Yesterday we made some alterations in the mounting of the great mirror. We found that sundry levers were loose which ought to be firm, and we conjectured with great probability the cause of this, for correction of which a change in other parts was necessary. The mirror was then found to preserve its position much more fixedly than before.... At night, upon trying the telescope, we found it very faulty for stars near the zenith, where it had been free from fault before. The screws which we had driven hard were then loosened, and immediately it was made very good. Then we tried with some lower objects, and it was good, almost equally good, there. For Saturn it was very greatly superior to what it had been before. Still it is not satisfactory to us, and at this time a strong chain is in preparation, to support the mirror edgeways instead of the posts that there were at first or the iron hoop which we had on it yesterday.