116 
Proceedings of the Royal Irish Academy. 
tliat day, and on previons days, to the study of the solar spectrum, as 
seen in the instrument I was using, so that I considered myself justi- 
fied in putting on record my estimate of the refrangibility of the line 
in the corona as being decidedly less than the refrangibility of E. Only 
for a few seconds was this remarkable spectrum seen, for a small cloud, 
which had begun to form to the west of the sun before totality, passing 
towards the east, and growing as it passed, shut out our view, the 
line fading steadily till I could no longer see it. 
On hearing from Sergeant E,ing the state of the case, I looked up at 
the place of the sun : nothing was visible save the drifting cloud, and 
above it a brilliant star, which proved to be the planet Yenus. 
As the end of totality drew near the little cloud passed rapidly off, 
and for a few seconds I saw the western side of the corona as a pearl 
white half circle, without rays, about 30^ or 35' broad. The Sergeant 
was at once ordered to set on the west limb of the moon. While 
he was doing so a brilliant bead like a star appeared nearly at the W. 
point and increased with immense rapidity ; the totality was passed, 
and nothing could now be done but the jotting down of the results of 
my labours, few and imperfect enough. The report of what I had 
seen was written down at once, before holding communication with 
any one. 
The sketching department was chiefly entrusted to Mr. John 
Brett, a gentleman who, happily, unites the peculiar qualifications of 
an astronomical observer with artistic powers of no mean order. It 
was fortunate that he had, not long before proceeding to join the 
Eclipse Expedition, furnished himself with a powerful reflector mounted 
so as to be peculiarly adapted for observations of the sun, the upper 
half of the tube being left open, an arrangement which almost entirely 
does away with tube currents of unequally heated air. As to the 
quality of the instrument, a few words will sufiice, namely, that the 
mirror was an Sl-inch With-Browning, the eyepieces Browning's 
achromatic, and the sun apparatus a Herschel prism with a neutral tint 
dark wedge. 
The atmospheric circumstances on the morning of the 22nd were 
unusually magnificent, the details of the solar surface and spots being 
beautifully defined and steady. 
About twenty minutes after first contact, Mr. Brett requested me 
to come to his telescope as he had detected a prolongation of the moon's 
limb beyond the cusps of the solar crescent. On examining the dis- 
tribution of light beyond the sun's image, both on and off the moon, 
it was very striking to see how very much more intense the faint ex- 
tension of light from the solar limb proper was than the extremely 
feeble luminosity which overspread the encroaching limb of the moon. 
Here was an observation of the corona in what was practically broad 
daylight, showing that if we had some means of producing the neces- 
sary contrast, the corona might be observed distinct from the general 
illumination of our own atmosphere on any really clear day. 
After all was over Mr. Brett made the remark that the appearance 
