1868.] Astronomy. 215 
hand-spectroscope and narrow chink, lines in the spectrum of the 
corona might be seen. Marine and meteorological phenomena 
never yet observed might also be noticed. 
Mr. Stoney, F.R.S., supplies a paper on the subject of the same 
eclipse. Viewing the corona which is seen during a total eclipse as 
caused by the sun’s enormous outer atmosphere projecting beyond 
the disc of the moon, he considers that the examination of this 
‘phenomenon through a spectroscope adapted to an equatorial tele- 
scope would be likely to yield results of extreme interest and im- 
portance. He points out that the shell of excessively faint cloud 
which seems to lie at a distance of 8” or 10" from the edge of the 
sun’s disc should be observed both from a central station and from 
stations close to the northern and southern limits of totality, so 
that we may be enabled to determine whether it is continuous all 
round the disc. It is desirable also that the flame-like protuber- 
ances should be examined, in order to determine whether their 
spectra resemble the solar spectrum, or on the other hand consist 
(some of them, at least) of bright lines. We should thus learn 
whether these objects resemble mists or true vapours. 
Mr. Stone apples a careful investigation to Professor New- 
combe’s determination of the solar parallax. Professor Newcombe 
deduces the solar parallax from the parallactic inequality in the 
earth’s motion, a method already applied by Leverrier, and described 
by us in a recent chronicle. But the value deduced by Professor 
Newcombe differs considerably from Leverrier’s. In place of a 
parallax of 891, Newcombe obtains the value 8"81. It will be 
remembered that the estimate of the moon’s mass is a very im- 
portant element in the inquiry. Newcombe makes the moon’s 
mass srs Of the earth’s ; Leverrier’s labours corrected by Stone gave 
the fraction sxx. After a careful revision of the processes applied 
by Leverrier and Newcombe, Mr. Stone arrives at the conclusion 
that Newcombe should have obtained the value 8-87 for the solar 
parallax, if his own estimate of the moon’s mass were adopted, and 
the value 889 if Leverrier’s estimate were taken. 
In a later paper Mr. Stone determines the moon’s mass in- 
dependently, retaining all terms of the third order in the Lunar 
Theory. He obtains the following relation :— 
Moon’s mass 
Earth’s mass —«- 81°38 
This result depends on the adopted values of Luni-Solar Precession 
(50"°378), and Nutation (9'"223). 
Mr. Stone deals also at length with Bessel’s Mean Refractions. 
From the existence of several small but systematic discordances, he 
had been led to form the opinion that the refraction-corrections 
used at Greenwich for zenith distances less than 85° are too great, 
