dicated when the comet appeared--a mere detail, perhaps, but
suggesting the possibility that cause and effect may have been
interchanged by mistake, and that it was Charles's abdication which
occasioned the appearance of the comet. According to Gemma's account the
comet was conspicuous rather from its great light than from the length
of its tail or the strangeness of its appearance. 'Its head equalled
Jupiter in brightness, and was equal in diameter to nearly half the
apparent diameter of the moon.' It appeared about the end of February,
and in March presented a terrible appearance, according to Ripamonte.
'Terrific indeed,' says Sir J. Herschel, 'it might well have been to the
mind of a prince prepared by the most abject superstition to receive
its appearance as a warning of approaching death, and as specially sent,
whether in anger or in mercy, to detach his thoughts from earthly
things, and fix them on his eternal interests. Such was its effect on
the Emperor Charles V., whose abdication is distinctly ascribed by many
historians to this cause, and whose words on the occasion of his first
beholding it have even been recorded--

"His ergo indiciis me mea fata vocant"--

the language and the metrical form of which exclamation afford no ground
for disputing its authenticity, when the habits and education of those
times are fairly considered.' It is quite likely that, having already
abdicated the throne, Charles regarded the comet as signalling his
retirement from power--an event which he doubtless considered a great
deal too important to be left without some celestial record. But the
words attributed to him are in all probability apocryphal.

The comet of 1577 was remarkable for the strangeness of its aspect,
which in some respects resembled that of the comet of 1858, called
Donati's. It required only the terror with which such portentous objects
were witnessed in the Middle Ages to transform the various streamers,
curved and straight, extending from such an object, into swords and
spears, and other signs of war and trouble. Doubtless, we owe to the
fears of the Middle Ages the strange pictures claiming to present the
actual aspect of some of the larger comets. Halley's comet did not
escape. It was compared to a straight sword at one visit, to a curved
scimitar in 1456, and even at its last return in 1835 there were some
who recognised in the comet a resemblance to a misty head. Other comets
have been compared to swo