232 
NATURE 

| Fuly 20, 1871 

many previous eclipses. Mr. Gilman says that at the com- 
mencement of totality—let me remind you, the commencement 
was determined by the disappearance of the sun at the east limb 
of the moon, which is east in Mr. Gilman’s drawing, as he was 
observing with the naked eye—the commencement, he says, was 
determined by the corona flashing out very much like a capital 
D. Yousee on the black board exactly the outline, and you 
will at once mentally associate one half of the diagram with the 
rays observed by M. Plantamour, and the other half, in which 
there is a nearly perfect ring of light round the moon, with the 
corona observed by Mr. Carrington all round it ina cloudless 
sky. At mid-eclipse Mr. Gilman also observed the corona, 
sketched out its outline carefully, and found rays coming out on 
the opposite side, adding themselves on to the perfect ring first 
seen there. Opposite the two salient angles he observed at the 
commencement of totality—represented by the top and bottom 
of the upright stroke of the capital I)N—there were two others; 
the corona now appeared square, and then, just before the end of 
totality came on, the two corners first seen were observed to dis- 
appear altogether, leaving nothing but a perfect ring, and where, 
at the beginning of the eclipse, nothing was seen buta perfectly 
round ring, the two exactly similar forms on the opposite side 
shot forth, and you got a [— reversed (CQ). Mr. Warrington 
Smyth, who drew a square corona, saw the light flash out into 
the corona before the end of totality, and believes that all the 
angles of the square were not visible at one and the same time. 
Here, then, you have observations of exactly the same charac- 
ter as those of M. Plantamour, to which I have referred. In 
the drawings of both are shown the inner part of the corona, 
which you saw growing in the observations of 1851, to which 
were added the strange forms observed in1858. You have these 
strange variations positively growing at the same place and the 
same time, in the same and in different eyes. Obviously there 
must be very much that is non-solar, call it personality, atmo- 
spheric effect, or what you will, connected with it. We have 
added to the stable the unstable. The question is, to what is 
this unstable portion due ? 
d.— They are very variously represented 
I will now refer to other drawings of the late eclipse, which 
were made in Sicily. For some reason or other, which I do 
not profess to understand, the corona, which appeared in Spain 
to be square, and to Mr. Gilman like a [PD at the beginning, and 
like a [ED reversed (C)) at the end,—to all those with whom I 
have conversed who saw it in Sicily, it appeared as round as you 
see it here, in this drawing made by Mr. Griffiths ; and, instead 
of being square, we had sent to us all sorts of pictures, a large 
number of them representing a stellate figure. Here is a drawing 
made by a Fellow of the Royal Society, on board one of Her 
Majesty’s ships (the Zord Warden) which were trying to save the 
poor Psyche at Catania. In this we have perfectly regular rays 
drawn from every region of the sun, some long, some short, but 
similar rays are a‘most invariably opposite each other ; but in the 
interior, inside these rays, the corona is just as it was observed by 
Mr. Griffiths at Syracuse. I now show you a drawing made by 
an American gentleman at sea, between Catania and Syracuse, 
with one ridiculously long ray, a ray as long as was seen by Otto 
Struve in 1860. Other drawings were made, even on board the 
same ship, so unlike each other, and so bizarre, that I need only 
refer to them as showing that there at all events must be sume 
personality. We have then to account for the variations between 
the observations made in Spain and those made in Sicily. I 
regret that we have not a third order of difficulties to contend 
with, as doubtless we should have had if observations had been 
made by Mr. Huggins’ party in North Africa. 
e.—The Rays are accompanied by a Mass of Light. 
These changes of the rays from side to side are accompanied 
by, and are perhaps to a certain extent due to, the bursting forth 
of brilliant light in their neighbourhood, where the limbs are 
nearest in contact. This was first observed by Miraldi in the 
eclipse of 1724, and has frequently been recorded since. Mr. 
Warrington Smyth, to whom I have before alluded, states that 
he noticed this in the last eclipse, and the photographs, I think, 
have recorded it ; but as there is some uncertainty on this point, 
I need only suggest it. 
j.—Long Rays are seen extending from the Cusps before and 
after Totality 
So far I have referred only to the rays visible during totality, 
but long rays were seen when a crescent of the sun was visible 


in 1860 and 1868 by Mr. Galton and Mr. Hennessy. Mr. Brett 4 
x 
caught the same phenomenon last year; but as the sky was — 
cloudy the commencements of the rays only were seen, — 
appearing like delicate brushes in prolongation of the cusps. 
These observations are of great value, as mo one for one moment — 
imagines that these rays are solar, and yet they are very like those 
seen during totality. 
g.—Sometimes Dark Rays, called Rifts, are seen instead of 
Bright ones 
Those rays to which I have referred are, however, not the only 
kind of rays that are observed. At times are seen, as it were, — 
openings in the corona; the openings being of the same shape as 
the rays, that is, expanding as they leave the dark moon, and | 
opening more or less exactly as the rays do. Like the rays also — 
they are sometimes very numerous ; in other eclipses they are — 
few in number, Let us take the eclipse observed in India in — 
1868. Several drawings made there showed the corona as square — 
as it was drawn in Spain last year; others as round as it was — 
seen in Sicily ; but the eclipse was not observed only in India, it 
was observed at Mantawalok-Kelee by Captain Bullock, and at — 
Whae-Whan, on the east coast of the Malayan Peninsula, by Sir 
Harry St. George Ord, Governor of the Straits Settlements. In 
the former place we had rifts expanding rapidly as they left 
the sun—one forms an angle of 90°, the sides of another being — 
paraliel—separating patches of corona, which in some places 
extends 24 diameters of the moon from the sun. 
At Whae-Whan we are told that at one,particular moment of 
the eclipse ‘‘it was noticed that from several points in the moon’s 
circumference darker rays emanated, extending to a considerable 
distance into space, and appearing like shadows cast forth into 
space by something not very well defined ;” these dark rays 
afterwards ‘‘ diminishing.” 
Now let us pass on to the eclipse of 1869. In two drawings 
made by Dr. Gould, in which the changes in the bright bundles 
of rays come out ina mest unmistakable way, we get similar rifts, 
which changed as violently as did the rays; while in another 
drawing made by Mr. Gilman, the whole corona is furrowed by 
narrow rifts in all regions lying between violet, mauve-coloured, 
white, and yellowish white rays ! 
Now, what have we bearing on this point in the recent 
observations? No rift was seez in Sicily ; one rift was recorded 
by the sketchers in Spain, but more than one rift was photo- 
graphed in both places. We must remember, however, in thus 
bringing eye-sketches and photographs into comparison, 
first that the eye too often in such observations retains a 
general impression of the whole phenomenon, while the plate 
records the phenomenon as it existed at the time at which it 
was exposed ; and secondly, that we know that the plates 
record chemically, while the eye records visually. We are dealing 
with two different kinds of light. 
I will show you two photographs on the screen. Although 
the lucid intervals were very rare, we were fortunate enough to 
get one photograph of the coronal regions in Syracuse, and one 
in Spain. I now show you the photograph made by the American 
party in Spain. You see here that, probably owing to a cloud, 
we get a certain amount of light driven on to the dark moon, 
and you also see the indications of the rifts. This photograph 
was taken with an instrument with a small field of view, so that 
the most important parts of the corona were rendered invisible 
by the instrument itself. 
Lord Lindsay, who also photographed in Spain, recorded no 
rifts. 
In the other photograph, taken at Syracuse, the result is better. 
We have the equivalent of the rift in the photograph I showed 
you before. The instrument was extremely unsteady, and the 
definition not so good as it would have been if Mr. Brothers had 
had a good opportunity of displaying his skill. We get other 
fainter indications of other rifts here and there, and the question 
whether these rifts agree in the photograph taken in Spain with 
those in that taken in Syracuse is one of great importance ; and 
it is to be hoped that before long it will be set at rest. Some 
observers think they agree ; others think they do not. 
But there is an important consideration based on that photo- 
graph, to which I must draw your particular attention. I have 
shown you the photograph as it may be thrown on the screen ; 
but in the photograph itself there are delicate details which it is 
impossible to reproduce. The dark portions in the corona indi- 
cated in the copy I have shown you are merely the bases of so 
many dark wedges driving out into space, like their prototypes 
S bP ae 
