The letters of Thomas William Webb to Arthur Cowper Ranyard volume I
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- Thomas William Webb
- Letter 1. [June 21, 1858]
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The letters of Thomas William Webb to Arthur Cowper Ranyard VOLUME I 1858-1873 Contents: Introduction Letters 1-148 Appendix I: Arthur Cowper Ranyard Appendix II: Biographical Notes Introduction The letters transcribed here were written by Thomas William Webb – with some by his wife Henrietta (and one by Sir John Herschel) - to Arthur Cowper Ranyard. They cover the years between 1858 and 1885. Letter 1, written when Ranyard was thirteen years old, may well not have been the first, though it is unlikely that many preceded it. What prompted the boy to write is not known. It is likely that having become interested in astronomy his teacher, Augustus de Morgan at University College school may have suggested that he wrote for advice. De Morgan was an eminent mathematician, an active Fellow of the Royal Astronomical Society. He would have read Webb’s contributions to the Monthly notices and perhaps met him at a meeting. As will be seen, the first formal, though encouraging, letters: “My dear Sir”, gradually became more informal and a thoroughgoing friendship developed. There is the sense that both Thomas and Henrietta saw in Ranyard the son they never had. It must be said that Thomas importuned the younger man by asking him to do all sorts of errands. They always wanted more of his company than he could give, or was prepared to give. However, that Ranyard valued the friendship can be deduced from his preserving so many of the letters which were deposited in the library of the RAS after his death. The transcription of these letters has been made possible by the kind agreement of the library committee of the RAS to allow digital imaging of the manuscripts. The cost was borne by a grant to the Webb-Share project by the Heritage Lottery fund to whom we express thanks. The work of transcription was done by a small research group in Hardwicke: Julie Jones, Astrid Mick, Irene Orchard, John Tittley, Paul Haley, Mark and Janet Robinson. The last named, with the help of the group, has edited the letters. It is hoped that the letters will be found of interest – probably to two main groups of people: those interested in the history of astronomy and those local and social historians interested in the life of a Victorian country vicar. Consequently both groups will probably be annoyed by too much or too little explanation. Also, apologies should be made for assuming that the reader cannot translate the French, German, Latin in the letters but once I had started to work out a rough translation (and some are very rough) it seemed a consistent rule to follow. I apologise for any errors in the placing of the footnotes – and they may be many. While it is no excuse, Microsoft word is not keen on files of 250 pages in length but at least the whole document is searchable. For those wishing to know more about the astronomers mentioned in the text we have appended brief biographical notes at the end of Volume II with a separate entry for Ranyard. And for those wanting to place Webb in the context of his parish of Hardwick there is a further appendix. Finally I would like to quote the same Augustus de Morgan mentioned at the beginning of the introduction. When writing a paper on Newton and his niece in 1885 he made the following remark: I have lengthened this paper by many digressions on collateral points, and have punctuated my title accordingly: the colons denote that the paper contains matters relative to the parties separately, as well as to their connexion. These offshoots may attract attention and may lead to evidence. Should anyone object to this accumulation of details, I remind him that he may skim or skip. Little matters, which give or revive knowledge of the times, are very useful additions; the smallest of them may be a clue. Janet Robinson March 2014 Letter 1. [June 21, 1858] Dear Sir, I am glad you persevered in your experiment with the little Telescope. I am not at all surprised that you could not distinguish Saturn’s Ring with the eye-lens that you have, as it requires a power of 30 or 40 times to bring it out and I should not suppose that the eye-lens would give you anything like so high a power. – that it will be worth while to try whether the object glass will not bear a higher power, as I think it probable it would. The rule for finding the magnifying power is very simple – it is the quotient obtained by dividing the focal length of the object glass by that of the eye-lens and if you have leisure, it might be instructive and amusing to you to ascertain the power you now have. In order to do this, you must take the object glass out of the tube, hold it up straight before the sun (or moon) and measure the distance in inches to a piece of paper or card, held exactly in the focus, where the image is formed smallest and sharpest defined – this is very easy with the crescent moon, as there is less uncertainty with it, than with the sun, where the image is most sharply formed. This is the principal focal distance, or focus for parallel rays.- Then you will have to do the same by the eye glass – and to divide the one by the other. Thus if the object glass has a focal length of 20 inches, and the eyeglass, one of 2 inches, you have at present a power of 10. And having the focal length of the object glass you will know what focus you will want for the eye-lens, to give you a chance of seeing the ring of Saturn – for instance, if your object glass has a focal length of 20 inches, and you want a power of 40 to shew the ring, an eye- I have found the study of Astronomy productive of so much interest and gratification, and that of so noble a kind, that it always gives me especial pleasure to assist any young or inexperienced student, and therefore I was very glad to hear from yourself, and beg that, if you feel so disposed, you would write to me at any time, and tell me of any difficulty that may occur to you, though I am well aware that five minutes talk is worth many letters; but I am so seldom in London, that I fear we have not much chance of meeting. I shall be publishing a book on Astronomy4 next season – probably about November, expressly for the use of young students and amateurs but I do not think you would find it very useful to yourself, till you are somewhat better provided with a telescope.
I remain
Dear Sir Yours very faithfully Thomas William Webb Hardwick Parsonage, Hereford, June 21. 1858 P.S. I thought I had Mr Baker’s numbers and left a blank to fill it in, but I cannot find it – I fancy however it is something like 277 – and I know you will find it on the South side, between Little Queen Street and Chancery Lane – I think nearest the former. Pdfs 1001, 1002, 1003, 1004 Letter 2. Three months later Hardwick Parsonage Hereford
Sept. 27. 1858 My dear Sir, It gave me great pleasure to hear from you again, and I shall always be glad to do so, whenever you are disposed to write. I am glad to find at any rate that you have got an astronomical Eyepiece, and still more glad that it has shewn you the objects you mention; your Object Glass cannot be a bad one to bear so high a power. – You will find it necessary occasionally, though not very frequently, to clean the eyepiece, and where this is the case you will find that it all unscrews in several places, and it becomes easy to wipe the glasses, but some caution is necessary in doing this, as they are very easily scratched or damaged – the best way is to use always either a piece of very soft wash leather, or an old real silk handkerchief – but in either case it ought to have been kept out of the dust. A little spirits of wine is a safe application to remove dirt from the glass. If the lenses are very small, and difficult to get at, a camel’s hair pencil, such as landscape painters use (with water colours) is the best thing to employ. I wish I could tell you where to look for Encke’s Comet1. I had instructions sent to me some time ago, but I have not been able to find them for you, and I have not seen it myself. I should scarcely think you would be able to see it with your glass. But I hope you will make all that you can, of every opportunity of studying the great Comet2 now visible, as it may be many years before we are permitted to witness such a brilliant one again. These objects are generally seen best with a low power – and if you can manage to take one of the old glasses belonging to the eye-end of your telescope and fit it into a paper tube, so as to turn it into an eye-piece, you will probably find it will give you a more beautiful view than a higher power – and for shewing the tail well a low power is absolutely necessary – in order that there may be field enough, and contrast enough with the surrounding dark sky. If your telescope performs as well as I should expect, you will be able to see some of its interesting features – for instance, the greater brightness of the two edges of the tail, indicating its real structure to be a hollow Cone - a form frequently observed in the tails of large Comets – the greater condensation of the left side of the tail (to the naked eye) as well as its curvature backwards – both which are generally referred to the resistance of the ether in which it moves – which though exceedingly slight, is not inappreciable. You might compare the length of the tail with the distance between any two stars in the Great Bear, and so ascertain how many degrees it appears to you to extend, by (  black for white, and inverted as in the telescope) - something such an envelope has been doubled, with a corresponding multiple tail arising from it. – Or, as in Halley’s comet in 1835, the nucleus under the powerful action of the unwonted solar heat, may throw out jets of light, fans or sectors, as they have been called – into the surrounding coma or haze something in this way or a streak of light may appear to issue opposite to the tail, and towards the Sun – an “anomalous tail” as it is called, of which I believe Mr Hind1 has already observed some trace. You have no doubt observed the yellowish colour of the whole phenomenon. I have been watching it, when the very cloudy weather has permitted, with a small but excellent telescope of 2¼ aperture; but it has not light enough to shew many of its details. I have received from America a very fine 5½ inch Achromatic Object Glass2 – I forgot whether I mentioned it to you my expectation of it: the maker speaks of it in very high terms and I should have been very glad to have got it into work before this time – but the people whom I employed in Birmingham to make a tube for it – 7 feet long – did it so badly that I had to send it back, and have not yet received it again – however if it does not come soon, and we should get a little clear sky, I shall be disposed to alter an old wooden tube so as to carry I am glad you saw one of the great meteors which have been noticed lately. I have not been fortunate enough to see any of them – but my time has been very much occupied, and excepting when the Comet has been visible I have Have you looked at the middle star of the Tail of the Great Bear? If your telescope behaves well, you will not only see it double, as it is to the naked eye – but the large star will be found to consist of two very close together – a real double star. With many good wishes for your success in your studies I remain My dear Sir, Yours very faithfully, Thomas William Webb
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