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The, as to the claim that these objects constitute a '<hi rend="underline">new discovery</hi>' by <unclear>Mr.</unclear> N. They | The, as to the claim that these objects constitute a '<hi rend="underline">new discovery</hi>' by <unclear>Mr.</unclear> N. They | ||
have been familiar to me as irregularly formed <hi rend="underline">granulations</hi> since the year 1830, | have been familiar to me as irregularly formed <hi rend="underline">granulations</hi> since the year 1830, | ||
+ | when I first saw them with my five-foot refractor by <unclear>Dollond</unclear>; and I might have thought | ||
+ | them something <hi rend="underline">new</hi>, 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 <hi rend="underline">a mixture of small points of unequal light</hi>." | ||
+ | (Sept. 9, 1792). This was quite enough to convince me that mine was <hi rend="underline">no new dis-</hi> | ||
+ | <hi rend="underline">covery in 1830</hi>. With my excellent 6⅓-inch(Engl.) refractor by <unclear>Merz</unclear>, 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 <hi rend="underline">surface</hi> | ||
+ | which could truly be compared to '<hi rend="underline">willow-leaves</hi>' (10 to 1); and rarely any <hi rend="underline">separate</hi> objects | ||
+ | of such proportions in the penumbra. | ||
+ | I have therefore strongly objected to the term '<hi rend="underline">willow-leaves</hi>' 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 '<hi rend="underline">rice-grains</hi>', because they are <hi rend="underline">not at all uniform</hi> in size | ||
+ | or proportion, and are therefore like <hi rend="underline">no particular kind of grain</hi>. Hence my preference | ||
+ | for the general term <hi rend="underline">granules</hi>, or <hi rend="underline">granulations</hi>. | ||
+ | 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 <hi rend="underline">Philos. Trans.</hi> for 1801; and his '<hi rend="underline">corrugations</hi>' are your '<hi rend="underline">granules</hi>', (both | ||
+ | good names); and the '<hi rend="underline">rice-grains</hi>' of Mr. Stone (not bad), and the '<hi rend="underline">willow-leaves</hi>' (very bad) | ||
+ | of Mr. Nasmyth. As you have not the <hi rend="underline">Phil. Trans.</hi> I send you a very rough tracing | ||
+ | of his section of the photosphere, which shews incontestably that the <hi rend="underline">corrugations</hi> he | ||
+ | depicts are identical with your '<hi rend="underline">granules</hi>', and are elevated portions (as you point out) | ||
+ | of the general surface of the photosphere." I will inclose a <hi rend="underline">tracing</hi> of the <hi rend="underline">tracing</hi> | ||
+ | which Mr. Fletcher has sent me. | ||
+ | As to the existence of these objects being claimed by Mr. Nasmyth as a <hi rend="underline">new discovery</hi>, | ||
+ | I can only apply to it the maxim of our clever countryman of old time, Bacon, - | ||
+ | "<hi rend="underline">The ignorant make many discoveries</hi>". - 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. Deda Rue, supposing from Mr N's positive | ||
+ | assertion, descriptions and drawing, that there really must be such objects on the sun, |
Revision as of 22:24, 18 September 2020
of it, "I accompany the drawing with a diagram (N.o2) which exhibits in a more definite
and clear manner the exact form of those remarkable structural details of the solar surface."
And again;- "Diagram N.o2 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. Deda Rue, supposing from Mr N's positive
assertion, descriptions and drawing, that there really must be such objects on the sun,