448 Chronicles of Science. [ July, 
Furthermore, it was shown * some years ago that, by holding one 
soda flame in front of another, the outer envelope of the front flame 
acted as an opaque screen to the brilliant yellow light radiating from 
the flame behind it; and that if this opaque part of the flame were intro- 
duced into the path of the light in a spectroscope, it would carve out 
of the most luminous portion Fratmhofer’s double black line D. 
Furthermore, if other metallic particles were allowed to colour the flame 
(e.g. lithium, thallium, &.) they would likewise act as opaque screens 
to rays of light of their own refrangibility, and would produce black 
lines, the exact counterparts of Fratinhofer’s lines, in the solar spec- 
trum. Now the portion of the flame possessing this great absorptive 
power is, upon examination, found to be a very faintly luminous 
exterior envelope, quite outside the luminous portion of the flame. 
Applying these facts to our theory of the solar envelopes, they fall 
into their places very naturally. The willow-leaves are the repre- 
sentatives of the atoms of incandescent metallic particles existing in 
our gas flame, whilst the highly-absorbent non-luminous outer enve- 
lope of the flame will represent the envelope of vapour which, on the 
sun’s surface, is the cause of the phenomena of Fratinhofer’s lines. 
At one of the recent meetings of the Literary and Philosophical 
Society of Manchester, Mr. Baxendell brought forward an hypothesis, 
based upon an investigation of magnetical and meteorological pheno- 
mena, which confirms, in an unexpected manner, one of the most 
recent conclusions in theoretical astronomy. The results of the 
elaborate investigations of the motions of the planet Mercury, made 
by M. Leverrier, led that mathematician to attribute a certain unex- 
plained excess in the motion of its perihelion to the action of a dis- 
turbing body circulating round the sun within the orbit of Mercury ; 
and from a discussion of the probable mass of the disturbing body, 
he concluded that it could not be concentrated in a single planet, but 
that it consisted of a ring of small bodies, similar to that which is 
known to exist between the orbits of Mars and Jupiter. This ring, 
however, owing to its proximity to the Sun, may never be seen, and 
like the dark companions of Procyon and Sirius, it may only be 
known to us through its action on the other bodies of the system, of 
which it forms a part. An elaborate discussion of meteorological 
and magnetic phenomena has now led Mr. Baxendell to the sup- 
positions— 
1. That a ring of nebulous matter circulates round the sun in a 
plane nearly coincident with that of the ecliptic—the density of this 
ring differing in different parts. 
2. That the attractive force of the sun on the ring varies inversely 
as the solar spots, being greatest when these are fewest, and least 
when the spots are most numerous. 
3. The attractive force being variable, the dimensions of the ring 
and its period of revolution round the sun will also vary, their 
maxima and minima occurring respectively at the times of maximum 
* “Crookes on the Opacity of the Soda Flame to Light of its own Colour.” 
‘Chemical News,’ vol. iii. p. 2. 
