ME. J. N. LOCKYEE ON SPECTEOSCOPIC OBSEEV ATION S OE THE SUN. 441 
superficie solare come un generale inviluppo transparente. Infatti il loro numero pro- 
digioso, e il loro estendersi per archi continuati di molti gradi, ci mostra che e irragio- 
nevole supporle, particolarita locali ed eccezionali sulla superficie solare, come sono le 
macchie, ne possono dirsi eruzioni vulcaniche di pochi punti: al contrario il vederle 
spuntare congiunte in lunghe catene tan to al principio che al fine della totalita, ci per- 
suade che' negli altri punti della circonferenza si rendono visibili solo le cime maggiori e 
piu elevati, restando le minor! e piu basse coperte dal corpo lunare.” 
Although these modem results would seem to have settled the question as far as it 
was possible to settle it by ordinary observations on the central line of totality, I cannot 
find that the idea of the continuity of the envelope was generally accepted in England 
or in France. 
In 1861 we find M. Faye* calling upon observers of the eclipse that was to happen 
on the last day of that year to examine “ si cette aureole (la partie de cette couronne 
la plus voisine du soleil) presente ou non le renversement du spectre solaire, c’est a 
dire si les raies obscures de Fraunhofer seront remplacees dans ce spectre par des raies 
brillantes.” There is not one word about the “ couche rose” of M. Le Verrier! 
After this in England we find General Sabine, Dr. Balfour Stewart, and Professor 
Challis independently arriving at the conclusion that the red flames are solar aurorae — 
a theory which I think plainly indicates that the idea that they formed part of a conti- 
nuous envelope was not in their minds. Mr, Balfour Stewart, in a Lecture at the Royal 
Institution f, remarked: — 
“ In support of this hypothesis it may be remarked that, during the late total eclipse 
in Spain, Mr. De La Hue, by means of the Kew photoheliograph, proved that these 
red flames belong to the sun, and that they extended in one case to the distance of 
70,000 miles beyond his photosphere. But, considering the gravity of the sun, we are 
naturally unwilling to suppose that there can be any considerable amount of atmosphere 
at such a distance from his surface ; and we are therefore induced to seek for an expla- 
nation of these red flames amongst those phenomena which require the smallest possible 
amount of atmosphere for their manifestation. Now the experiments of Mr. Gassiot, 
and the observed height of the terrestrial aurora alike convince us that this meteor will 
answer our requirements best. And besides this, the curved appearance of these red 
flames, and their high actinic power in virtue of which one of them, not visible to the 
eye, was photographed by Mr. De La Hue, are bonds of union between these and 
terrestrial aurorae.” 
Although Mr. De La Eue in his Memoir refers to the prominences being scattered 
widely over the sun’s disk, it was not till December 1867 that the real meaning of the 
photographs in this particular was grasped. Mr. Stoney, in a paper communicated to 
the Royal Astronomical Society in that month, in which he refers to his hypothesis that 
the sun has an enormous atmosphere, which in eclipses projects far beyond the disk of 
* Comptes Bendus, vol. lii. p. 679. 
f Proceedings of the Boyal Institution, vol. iv. p. 60. 
3 N 
MDCCCLXIX. 
