and World of Science,' for October 27, 1876, p. 160),
that Vulcan might perhaps better be called the 'planet of fiction' was
_pro tanto_ confirmed. Nevertheless, I would not be understood to mean
by the word 'fiction' aught savouring of fraud so far as Lescarbault is
concerned--I prefer the North Briton's view of Lescarbault's spot, that
so to speak, it was

... the blot upon his brain,
That _would_ show itself without.

I have left small space to treat of other fancied discoveries among the
orbs of heaven. Yet there are some which are not only interesting but
instructive, as showing how even the most careful observers may be led
astray. In this respect the mistakes into which observers of great and
well deserved eminence have fallen are specially worthy of attention.
With the description of three such mistakes, made by no less an
astronomer than Sir W. Herschel, I shall bring this paper to a close.

When Sir W. Herschel examined the planet Uranus with his most powerful
telescope he saw the planet to all appearance girt about by two rings at
right angles to one another. The illusion was so complete that Herschel
for several years remained in the belief that the rings were real. They
were, however, mere optical illusions, due to the imperfect defining
qualities of the telescope with which he observed the planet. Later he
wrote that 'the observations which tend to ascertain' (indicate?) 'the
existence of rings not being satisfactorily supported, it will be proper
that surmises of them should either be given up, as ill-founded, or at
least reserved till superior instruments can be provided.'

Sir W. Herschel was more completely misled by the false Uranian
satellites. He had seen, as he supposed, no less than six of these
bodies. As only two of these had been seen again, while two more were
discovered by Lassell, the inference was that Uranus has eight
satellites in all. These for a long time flourished in our text-books of
astronomy; and many writers, confident in the care and skill of Sir W.
Herschel, were unable for a long time to believe that he had been
deceived. Thus Admiral Smyth, in his 'Celestial Cycle,' wrote of those
who doubted the extra satellites:--'They must have but a meagre notion
of Sir W. Herschel's powerful means, his skill in their application, and
his method of deliberate procedure. So far from doubting there being six
satellites' (this was before Lassell had discovered the other two) 'it
is h