Fan. 5, 1871 | 
NATURE 
195 

THE ECLIPSE EXPEDITION 
jae we intimated last week, the weather was more or 
less unfavourable at nearly all the stations for the 
observation of the Total Eclipse of Dec. 22nd. We give, 
in another column, an account of the preparations made 
by the Sicilian department of the Expedition, received by 
us. The following account of the results obtained at some 
of the other stations is compiled chiefly from reports fur- 
nished to the Zvmes and Daily News. 
From Cadiz we have an interesting account by the Rev. 
S. J. Perry, as follows :— 
“The situation of San Antonio is found to be lat. 36° 
37 13” N., long. 24’ 15” W. of Greenwich. Time signals 
were daily received from the San Fernando Observatory, 
and all our chronometers carefully rated by Capt. Toynbee. 
Our thirteen observers were distributed as follows: Mr. 
Moulton, of Christ’s College, Cambridge, with Mr. Baines, 
of Oxford, were to observe with the polariscope at San- 
lucar, the extreme W. point on the Spanish central line 
of totality, and 12 miles N.W. of San Antonio. Near 
Xeres, 5 miles N.E. of San Antonio, were stationed Mr. 
P. Naftel, for an eye sketch of the corona, Mr. F. C. Pen- 
rose to sketch the same as seen through a telescope, and 
Mr. Abbay, of Wadham College, Oxford, to observe with 
the spectroscope. Mr. W. Smyth sketched near Arcos, 
17 miles E.N.E. of San Antonio, using a telescope of the 
same aperture as that of Mr. Penrose. The rest of the 
observers remained at San Antonio. At this station the 
spectroscopic observers were Capt. Maclear, R.N., and 
myself, assisted by Mr. Hostage. Polarisation was to be 
observed by Mr. Hudson, of St. John’s, Cambridge, and 
Mr. Ladd, optician ; and an eye sketch of the corona to 
be made by Mr. Browne, of Oxford. The weather has 
been unexceptionally bad ever since our arrival, the only 
fine day being the 21st. Our observers were therefore 
spread out as much as possible, in hopes of not failing 
altogether on account of bad weather. The results justi- 
fied our anticipations. The fine weather of the 21st lasted 
but a day, and at two A M. of the 22nd the clouds and rain 
returned. At San Antonio a break only came some 48° 
after first contact, when a distinct notch was observed on 
the solar disc. This break was only a change from thick 
cloud to thin cirrhus, but we were enabled to observe the 
time of contact of the limb of the moon with several of the 
more remarkable solar spots. In the north the sky was 
partially clear, but in the south no part of the heavens 
was free from cloud. A very striking change of light on 
the landscape was noticed when little more than three- 
fourths of the solar disc was covered, and a chill was felt 
by all. The thermometer observed by Capt. Toynbee fell 
3°F. from the commencement to totality, and rose again 
1'7° before the end of the Eclipse. The barometer was 
falling rapidly all the time of the Eclipse, and also after- 
wards, at the rate of o’04 in. an hour. The wind was W. by 
N. true. During totality it lulled, but freshened afterwards 
with very heavy rain. The moment of totality approached, 
and no chance remained of even a momentary break in 
the thin cirrhus that enveloped the sun, and obscured 
most of the southern heavens. As the crescent became 
thinner, the cusps were observed first to be drawn out a 
length of several minutes, and then blunted ; the well- 
known Baily beads were formed, and the corona burst 
forth more than 20° before totality. Viewed through a 
telescope of very maderate dimensions the spectacle was 
grand, but the cirrhus clouds destroyed almost all the 
grandeur of the effect for the naked eye. The red 
prominences were numerous, but none apparently very 
remarkable; Mr. W. H. Browne, of Wadham College 
Oxford, considers their colour to have been ef a bright 
yellowish red tint. The same observer notices that the 
corona was perfectly free from striation, outline distinct, 
and approximately quadrilateral, but extending farthest 
in the direction of first contact. The brightest part of 

the corona appeared to the unassisted eye to be scarcely 
more than one-tenth of the sun’s diameter, fading rapidly 
when one-fifth, but being still clearly visible at seven- 
eighths. Some observed two curved rays, but the general 
appearance was that of a diffuse light interrupted in four 
places distinctly, and in a fifth faintly, by dark intervals. 
| The corona was white, and rendered faint by the clouds. 
The darkness was never sufficient to prevent sketching 
with comfort without the aid of a lamp. Venus alone 
was visible. Totality ended by the formation of Baily’s 
beads, and the corona was visible to the naked eye 155 
or 16° after totality. The corona was seen for 2™ 50°, 
totality lasting less than 2™ 10°, The clouds obscuring 
the sun appear to have destroyed almost all chance of 
detecting any except atmospheric polarisation. Mr. Ladd 
remarked that the polarisation was stronger on the corona 
than on either the moon’s surface or the cloudy sky. 
“No report has as yet been received of the polarisation 
observations at Sanlucar. The observations with the 
spectroscope were also greatly interfered with by the 
cirrhus, and the best instrument was rendered entirely 
useless. The intensity of the light from the corona, as 
seen through the clouds, could not, I think, have been 
more than one-eighth of that of the bright moon, if so 
much, and, consequently, I was unable to detect the 
faintest trace of light through the three compound prisms 
I was using. The chances of observing satisfactorily, 
considering the state of the sky, were greatly diminished 
by the largeness of the direct image given by the Casse- 
grain I was compelled to use. Knowing that an un- 
favourable sky would render observations with a powerful 
Spectroscope quite impracticable, I desired Captain 
Maclear to observe with a small direct vision Browning 
spectroscope, attached to a four-inch achromatic by 
Jones, mounted equatorially. The slit was placed radial 
at the centre of the east limb, and close to it, and im- 
mediately totality commenced the ordinary solar spectrum 
was replaced by a faint diffused light, and bright lines 
near C, D,b (or E),and F. No absorption bands. The 
slit was then removed to a distance about 8’ from the 
limb, and the same lines remained visible. The centre 
of the moon was next tried, and the bright lines were 
still seen, but only half as strong as before. The slit was 
then placed 8’ outside the W. limb, and the lines became 
as strong as before, and were C, D, one three-quarters of 
the distance from D to E, and another half way between 
Eand F. Lastly, placing the slit near the sun (on a 
prominence) two new green lines, and a very brilliant line 
beyond F, were added to those already visible, but the 
line near E may have disappeared. The lines seen on 
the moon were, I suppose, due to the diffusive power of 
the cirrhus clouds ; and the same may perhaps be true of 
the apparent coronal lines. 
“Mr. Abbay, observing at Xeres with a spectroscope 
of two prisms of 45°, belonging to Professor Young, saw 
the bright lines C, D, F; and afterward F, and a line 
rather more bright than F, at some distance on the 
less refrangible side of B, C not noticed then. These 
two observations were, I think, taken at points external 
to the prominences, but I cannot at present speak 
with certainty, as no note to that effect is entered 
in the memoranduin I received. A comparison of these 
observations with those of other observers more favoured 
than ourselves will doubtless lead to valuable results. 
Shortly after totality the clouds thickened still more, and 
nothing further could be observed.” 
The view of the Eclipse obtained near Arcos is described 
as very magnificent ; a sketch was made there by Mr. 
Warrington Smyth. At the American station near Xeres 
there was a break in the clouds, which lasted somewhat 
more than half the totality. But Lord Lindsay’s party 
was the most favoured in this country, having seen the 
sun through a rent in the clouds for five minutes, and this 
time embracing the whole of totality. Mr. O. Airy and 
