ECLIPSE OF THE SUN, APRIL 25, 1865, 259 
_western border of the moon presented a magnificent ring of some seconds in 
breadth and of a violet-blue color. Its regularity was perfect. It was rather a 
luminous outburst of admirable effect. Nothing like it was manifested on the 
side of the eastern border. The ring of the corona was, nevertheless, well 
closed, and of a perfect pearl color, except on the eastern side, where the feeble 
line of solar light gave it the ordinary tint of the atmosphere near the edge of the 
sun. Five pencils of parallel rays of a perfect whiteness proceeded, almost per- 
pendicularly, and without blending, from the edge of the ring of the corona. 
None of these pencils seemed to me contiguous to the lunaredge. If we except 
the violet-blue coruscation which showed itself on the western border of the moon 
at the height of the eclipse, nothing was observed which resembled those flames 
or protuberances which are almost constantly remarked in total eclipses, unless 
we suppose to be such the same magnificent luminous ¢razt of violet blue of 
which I have spoken. 
Perhaps the short duration of theeclipse, and the illumination, however feeble, 
of the eastern edge of the sun, prevented their being distinguished at our station. 
We shall learn what will be said on this subject by the expeditions of St. Cath- 
erina and Cabo-Frio.* Notwithstanding the instantaneousness of the phenome- 
non, I endeavored to verify the existence of the polarization of the light of the 
corona. For this purpose I availed myself of the polariscope with colored 
bands of Savart, and that of M. Babinet. It was with the former instrument 
that I best recognized the polarization. The bands were well colored on direct- 
ing the instrument on the corona. The coloration was sufficiently sensible to 
forbid my admitting the intervention of the atmospheric polarization, for it was 
imperceptible when the instrument was directed on the lunar centre. It need 
not be said that the atmosphere-was strongly polarized in all its regions, during 
the continuance of the phenomenon, in the manner in which it ordinarily is. 
One circumstance, manifested with much distinctness, was the visibility of the 
border of the moon beyond the solar disk during even the first phase of the 
eclipse. Arago, however, had remarked it in 1842, and you have also called 
attention to it in your observation of 1858 with regard to photographic tests 
by causing the solar image to fall upon unpolished glass. During the whole 
eclipse I carefully explored in the photosphere the solar surface which showed 
the greatest calm. By a singular defect the faculee were scarcely perceptible 
in my instrument. Should the observations at St. Catherina and Cabo-Frio 
verify the absence of protuberances, the opinion will receive strong confirma- 
tion which supposes them to be formed by the ascending currents of solar 
vapors, which then involve by their impulsion the clouded extraphotospheric 
stratum, and whose violent elevation produces the protuberances. The photo- 
sphere was tranquil, and only a luminous line of a violet-blue color, a regular 
level stratum, presented itself to view. I sought with care for the existence of 
moving shadows. Nothing, however, was verified, although a large number of 
scholars of the Central school, who were then at the observatory, had their eyes 
fixed on the white walls of the cupola, favorably disposed for observation. The 
sky was so cloudy that we could perceive at our station only the planet Venus. 
The inhabitants, however, of places more to the south are said to have dis- 
cerned several stars of the first magnitude.t The leaden color tending to 
violet predominated in the air and on the sea, which resembled molten lead. 
Domestic animals manifested the usual phenomena, the fowls seeking their 
roosts, while certain species of brutes seemed to manifest rather surprise than 
fear. Of the horses.and mules in the streets of Rio de Janeiro, nothing re- 
* Letters of a later date than that of Baron de Prados have informed us that these two ex- 
peditions encountered such bad weather as to preclude observations. 
t To the south of Rio de Janeiro the eclipse, according to other information, was abso- 
lutely total. 
