not
venture back again for seventy-five years!" Of course this bit of
supposed information is all nonsense; Calixtus did no such thing, and
just at that time the Popes were encouraging Cardinal Nicholas of Cusa
in his great mathematical work and astronomical speculations, were
inviting Regiomontanus, "the Father of modern astronomy," down to Rome
to do his work there and help in the correction of the calendar, while
Cardinal Bessarion, one of the most intimate friends of the Pope at
this time, was encouraging Purbach at Vienna and Regiomontanus to
translate Ptolemy and providing them with manuscripts and putting them
in touch with Greek science in every way.

{511}

Halley's comet is a favorite reference with Professor Draper. How well
his readers must have remembered all about it! He says, for instance,
on page 320:

"The step that European intellect had made between 1456 and 1759 was
illustrated by Halley's comet. When it appeared in the former year,
it was considered as the harbinger of the vengeance of God, the
dispenser of the most dreadful of his retributions, war, pestilence,
famine. By order of the Pope, all the church-bells in Europe were
rung to scare it away, the faithful were commanded to add each day
another prayer; and, as their prayers had often in so marked a
manner been answered in eclipses and droughts and rains, so on this
occasion it was declared that a victory over the comet had been
vouchsafed to the Pope. But, in the meantime, Halley, guided by
revelations of Kepler and Newton, had discovered that its motions,
so far from being controlled by the supplications of Christendom,
were guided in an elliptic orbit by destiny. Knowing that Nature had
denied to him an opportunity of witnessing the fulfilment of his
daring prophecy, he besought the astronomers of the succeeding
generation to watch for its return in 1759, and in that year it
came."

All this is of course mere persiflage once it is known that the story
of the Papal Bull against the comet has no foundation in history. It
is the sort of nonsense that a great many serious men permit
themselves to indulge in when they think they are convicting some past
century of sublime foolishness. Not infrequently they make themselves
out just as absurd as they would like to present the men of former
generations, because they show how credulous a modern scholar can be
when his prejudices influence him. Unfortunately su