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of it, "I accompany the drawing with a diagram (№2) which exhibits in a more definite and clear manner the exact form of those remarkable structural details of the solar surface." And again;- "Diagram №2 conveys a pretty clear idea of the manner in which these remark- able details are arranged, in forming, as they do, the entire luminous surface of the sun." Therefore regard this as a fanciful theory which has no foundation in fact. But is it not extraordinary that, after so clear and decided a statement, Mr. Nasmyth should accept Mr. Stone's 'rice-grains' as being identical with his'willow-leaves,' even on the surface? - objects whose proportion is as 2 to 1, the same as those which are as 10 to 1! This seems to me to give up the willow-leaves on the surface, and to destroy the assumed value of Mr. N.'s first observations. The, as to the claim that these objects constitute a 'new discovery' by Mr. N. They have been familiar to me as irregularly formed granulations since the year 1830, when I first saw them with my five-foot refractor by Dollond; and I might have thought them something new, if I had not met with Sir Mr. Herschel's description of them as seen with his reflectors: "There is all over the sun a great unevenness in the surface, which has the appearance of a mixture of small points of unequal light." (Sept. 9, 1792). This was quite enough to convince me that mine was no new dis- covery in 1830. With my excellent 6⅓-inch(Engl.) refractor by Merz, and the transparent glass diagonal which Sir John Herschel had suggested in his "Cape Observations" in 1847, I said these in 1848 far better than before; the longer aperture giving sharper images, and allowing the use of higher powers. But when I had contrived my Solar Eye-piece, I found that the definition with it was rather sharper still, and I always preferred it, unless I required a large field of view. From that time to the present I have diligently availed myself of every good opportunity of scrutinizing the solar surface with excellent object-glasses up to 8¼-inch(Engl) aperture; but I have never found any objects on the surface which could truly be compared to 'willow-leaves' (10 to 1); and rarely any separate objects of such proportions in the penumbra. I have therefore strongly objected to the term 'willow-leaves' as applied to the photosphere, because there is nothing like them to be found there. Also (but in a much less decided way) to the term 'rice-grains', because they are not at all uniform in size or proportion, and are therefore like no particular kind of grain. Hence my preference for the general term granules, or granulations. One of your best observers, Mr. Isaac Fletcher, who has a very perfect refractor (by Cooke & Sons, of York) of nearly the same size as your own (9½ Engl. inches), has lately given very careful attention to the solar photosphere, and has thus expressed the results in a letter to myself: "It is perfectly clear, as you pointed out, that the appearances in question were perfectly familiar to Sir Mr. Herschel; as is abundantly shewn by his paper in the Philos. Trans. for 1801; and his 'corrugations' are your 'granules', (both good names); and the 'rice-grains' of Mr. Stone (not bad), and the 'willow-leaves' (very bad) of Mr. Nasmyth. As you have not the Phil. Trans. I send you a very rough tracing of his section of the photosphere, which shews incontestably that the corrugations he depicts are identical with your 'granules', and are elevated portions (as you point out) of the general surface of the photosphere." I will inclose a tracing of the tracing which Mr. Fletcher has sent me. As to the existence of these objects being claimed by Mr. Nasmyth as a new discovery, I can only apply to it the maxim of our clever countryman of old time, Bacon, - "The ignorant make many discoveries". - Mr. N. had never before examined the Sun with a suitable telescope: and as he was not acquainted with Mr. Herschel's obser- vations or my own, he thought that what he saw had never been seen before; and most unfortunately, Sir John Herschel and Mr. De La Rue, supposing from Mr N's positive assertion, descriptions and drawing, that there really must be such objects on the Sun,

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