THE ECLIPSE EXPEDITIONS. 
43 
The polariscopic observations at Oran are to be made by Mr. 
Carpenter, of the Greenwich Observatory. 
As regards the results which are to be expected from these 
four expeditions, supposing the weather to be favourable, it 
does not seem to me difficult to form an opinion. 
In the first place, it must not be concealed that, in this as in 
all former eclipse expeditions, no inconsiderable proportion of 
the suggested observations are likely to be of no practical 
utility whatever. For example, there can be no question that 
all the observations which are directed solely to determine 
whether the corona is a solar appendage will simply involve a 
waste of labour. It has been a misfortune that any doubts 
should have been started respecting a matter so thoroughly de- 
monstrated ; but this misfortune it is now too late to remedy. 
Nor must we forget that in former instances an even larger 
proportion of observing energy has been thrown away. For 
when, in 1860, not only England but France, Italy, Germany, 
and other countries sent forth their astronomers to view the 
Spanish eclipse, the doubts which Faye and others had urged 
respecting the reality of the prominences influenced more than 
nine-tenths of the observers. Nearly a hundred astronomers 
and observers endeavoured to find out whether the prominences 
are real solar phenomena, or mere illusions — lunar mirages, 
perhaps, as Faye had suggested ; and it would be difficult, 
indeed, to say how much knowledge which, but for these ill- 
considered doubts, might have been acquired, was thrown away 
on that inauspicious occasion. The success of De la Eue and 
Secchi in photographing the eclipsed sun does indeed serve to 
render the eclipse observations of 1860 memorable, and in a 
sense to hide from our view the real failure of astronomers at 
that time. But the very success of the two who chose to work 
independently and usefully, only causes us to deplore the more 
that thirty times as many preferred to waste their energies in 
demonstrating the demonstrated. 
On the present occasion, however, those who have pleaded 
for useful observations have not been wholly unsuccessful. A 
relatively small proportion of observing energy is to be devoted 
to demonstrate the abundantly demonstrated fact that the 
corona is a solar appendage.* Nearly all the most skilful tele- 
scopists and spectroscopists propose to inquire what the actual 
constitution of the corona may be, regarding its position — very 
* I am told that, in a recent number of u Nature,” it is remarked in a leader 
that, “ despite some hard writing to the contrary, the position of the corona 
remains to be proved.” This is in a sense true j and so, also, it is true that 
every proposition of Euclid (as, for instance, Prop. 5, Book I.) remains to be 
proved, as far as some learners are concerned. 
