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e sometimes bridged over by a streak of light； formed of willow…leaf…shaped objects。 They were apparently possessed of voluntary motion； and moved from one side of the spot to the other。 These flakes were evidently the immediate sources of the solar light and heat。 I wrote a paper on the subject； which I sent to the Literary and Philosophical Society of Manchester。* ＇footnote。。。 Memoirs of the Literary and Philosophical Society of Manchester； 3d series； vol。 i。 p。 407。 My first discovery of the 〃Willow…leaf〃 objects on the Sun's surface was made in June 1860。I afterwards obtained several glimpses of them from time to time。But the occasions are very rare when the bright sun can be seen in a tranquil atmosphere free from vibrations； and when the delicate objects on its surface can be clearly defined。 It was not until the 5th of June 1864 that I obtained the finest sight of the Sun's spots and the Willow…leaf objects； it was then that I made a careful drawing of them； from which the annexed faithful engraving has been produced。 Indeed I never had a better sight of this extraordinary aspect of the Sun than on that day。 。。。＇
The results of my observations were of so novel a character that astronomers for some time hesitated to accept them as facts。 Yet Sir John Herschel； the chief of astronomers； declared them to be 〃a most wonderful discovery〃
＇Image＇ Group of sun spots as seen by James Nasmyth； 5th June 1864。
I received a letter from Sir John； dated Collingwood； 2lst of May 1861； in which he said：
〃I am very much obliged to you for your note； and by the sight of your drawings； which Mr。 Maclaren was so kind as to bring over here the other day。 I suppose there can be no doubt as to the reality of the willow…leaved flakes； and in that case they certainly are the most marvellous phenomena that have yet turned uphad almost said in all Naturecertainly in all Astronomy。
〃What can they be？ Are they huge phosphorised fishes？ If so； what monsters！ Or are they crystals？ a kind of igneous snow…flakes？ floating in a fluid of their own； or very nearly their own； specific gravity？ Some kind of solidity or coherence they must have； or they would not retain their shape in the violent movements of the atmosphere which the change of the spots indicate。
〃I observe that in the bridges all their axes have an approximate parallelism； and that in the penumbra they are dispersed； radiating from the inside and the outside of the spot； giving rise to that striated appearance which is familiar to all observers of the spots。
〃I am very glad that you have pitched your tent in this part of the world； and I only wish it were a little nearer。 You will anyhow have the advantage at Penshurst of a much clearer atmosphere than in the north； but here； nearer the coast； I think we are still better off。 〃Mr。 Maclaren holds out the prospect of our meeting you at Pachley at no distant period； and I hope you will find your way ere long to Collingwood。 I have no instruments or astronomical apparatus to show you； but a remarkably pretty country； which is beginning to put on （rather late） its gala dress of spring？'
Sir John afterwards requested my permission to insert in his Outlines of Astronomy； of which a new edition was about to appear； a representation of 〃the willow…leaved structure of the Sun's surface；〃 which had been published in the Manchester transactions；to which I gladly gave my assent。 Sir John thus expresses himself on the subject： 〃The curious appearance of the 'pores' of the Sun's surface has lately received a most singular and unexpected interpretation from the remarkable discovery of Mr。 J。 Nasmyth； who； from a series of observations made with a reflecting telescope of his own construction under very high magnifying powers； and under exceptional circumstances of tranquillity and definition； has come to the conclusion that these pores are the polygonal interstices between certain luminous objects of an exceedingly definite shape and general uniformity of size； whose form （at least as seen in projection in the central portions of the disc） is that of the oblong leaves of a willow tree。 These cover the whole disc of the Sun （except in the space occupied by spots） in countless millions； and lie crossing each other in every imaginable direction。。。。 This most astonishing revelation has been confirmed to a certain considerable extent； and with some modifications as to the form of the objects； their exact uniformity of size and resemblance of figure； by Messrs。 De la Rue； Pritchard and Stone in England； and M。 Secchi in Rome。〃
On the 25th of February 1864； I received a communication from Mr。 E。 J。 Stone； first assistant at the Royal Observatory； Greenwich。
The Astronomer…Royal； he said； 〃has placed in my hands your letter of February 20。 Your discovery of the 'willow leaves' on the Solar photosphere having been brought forward at one of the late meetings of the Royal Astronomical Society； my attention was attracted to the subject。 At my request； the Astronomer…Royal ordered of Mr。 J。 Simms a reflecting eye…piece for our great equatorial。 The eye…piece was completed about the end of January last； and at the first good opportunity I turned the telescope on the Sun。
〃I may state that my impression was； and it appears to have been the impression of several of the assistants here； that the willow leaves stand out dark against the luminous photosphere。 On looking at the Sun； I was at once struck with the apparent resolvability of its mottled appearance。 The whole disc of the Sun； so far as I examined it； appeared to be covered over with relatively bright rice…like particles； and the mottled appearance seemed to be produced by the interlacing of these particles。
〃I could not observe any particular arrangement of the particles； but they appeared to be more numerous in some parts than in others。 I have used the word 'rice…like' merely to convey a rough impression of their form。 I have seen them on two occasions since； but not so well as on the first day； when the definition was exceedingly good。
〃on the first day that I saw them I called Mr Dunkin's attention to them。 He appears to have seen them。 He says； however； that he should not have noticed them if his attention had not been called to them。〃
The Astronomer Royal； in his report to the Admiralty on my discovery； said：
〃an examination of the Sun's surface with the South…East Equatorial； under favourable circumstances； has convinced me of the accuracy of the description； which compares it with interlacing willow leaves or rice grains。〃
In March 1864 I received a letter from my friend De la Rue； dated from his observatory at Cranford； Middlesex； in which he said： 〃I like good honest doubting。 Before I had seen with my own eyes your willow leaves； I doubted their real existence； but I did not doubt your having seen what you had drawn。 But when I actually saw them for the first time； I could not restrain the exclamation； ' Why； here are Nasmyth's willow leaves！ ' It requires a very fine state of the atmosphere to permit of their being seen； as I have seen them on three or four occasions； when their substantial reality can no longer be doubted。〃* ＇fo