Autobiography of Sir George Biddell Airy, George Biddell Airy [dark books to read TXT] 📗

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.

"In the operations of 1836 and 1837 a great quantity of papers