364 De la Rue and Celestial Photography. [July, 
mena to those just described. In 1836, on the occasion of the 
annular eclipse of May 15, Mr. Baily noticed a very striking 
appearance, which he thus describes: “ When the cusps of the sun 
were about 40° asunder, a row of lucid points like a string of bright 
beads, irregular in size and distance from each other, suddenly 
formed round that part of the circumference of the moon that was 
about to enter on the sun’s disc.” The same phenomenon occurred 
in a reverse order at the dissolution of the annulus. This pheno- 
menon had been observed previously (but never so perfectly described 
as it was by Mr. Baily*) by Halley in 1715, by Delisle in 1724, 
by Professor Bayne in 1737, by the Rev. Mr. Irvine in 1748, by 
Mr. 8. Webber in 1791,t and some others. Subsequent to Mr. 
Baily’s observations no opportunity has been lost by astronomers ; 
and other and yet more remarkable phenomena have claimed especial 
attention. By far the most striking, and we may almost say mex- 
plicable, are the red protuberances which appear on the edge of the 
sun when all the direct radiations are obscured by the body of the 
moon. 
The earliest notice which we have of those red protuberances 
beyond that of Rydhenius, already spoken of, is to be found im an 
account of the total eclipse of 1733, by Vassenius, in the ‘ Philo- 
sophical Transactions of the Royal Society.{ Vassenius speaks of 
them as “some reddish spots which appeared in the lunar atmo- 
sphere without the periphery of the moon’s disk.” These red spots 
appear to have attracted occasional attention; but it was not until 
the eclipse of 1842 that any degree of close observation was directed 
to them. M. Mauvais, who observed this eclipse at Perpignan, 
described the phenomenon as observed by him. He says, “I 
cannot give a more exact idea of their aspect than by comparing 
them to the peaks of the Alps illuminated by the setting sun, and 
seen afar off.”’§ M. Mayette, an officer of the French Engineers, 
compared the protuberances, as seen by him, also from Perpignan, 
to beautiful sheaves of flames. Each observer who has written on 
this eclipse has described the phenomenon as seen from the several 
points of observation along the line of totality. Mr. Baily, who 
was at Pavia, wrote of the luminous protuberances as having the 
appearance of mountains of a prodigious elevation, the colour of 
the peach blossom nearly representing their aspect.|| Mr. Airy was 
near Turin. He remarks that “in form they somewhat resembled 
saw-teeth in the position proper for a circular saw.” {| 
M. Littrow, of Vienna, and M. Otto Struve, have given carefully 
* ‘Memoirs of Astronomical Society,’ vol. x., p. 7. 
+ Consult ‘ History of Physical Astronomy,’ by Robert Grant, F.R.A.S. 
} ‘Philosophical Transactions, 1733,’ p. 135. 
§ ‘Annuaire, 1846,’ p. 409. 
| ‘ Memoirs of Astronomical Society,’ vol. xv., p. 6. 4 Ihid., p. 16. 
