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Edmund Halley, A Synopsis of the astronomy of comets

Prodigious Comet of the Years 1680, 1106, 531, -44.

At lenght, came the prodigious Comet of the Year 1680 which descending (as it were from an infinite Distance)
perpendicularly towards the Sun, arose from him again with as great a Velocity.
This Comet, (which was seen for four Months continually)
by the very remarkable and peculiar Curvity of its Orb (above all others)
gave the fittest Occasion for investigating the Theory of its Motion.
And the Royal Observatories, at Paris and Greenwich, having been for some Time founded,
and commited to the Care of most excellent Astronomers,
the apparent Motion of this Comet was most accurately (perhaps as far as human skill cou'd go)
observ'd by Mr. Cassini and Flamsteed.
But, as far as Probability from the Equality of Periods, and similar Appearence of Comets, may be urged as an Argument,
the late wondrous Comet of 1680 seems to have been the same,
which was seen in the Time of our King Henry I. Anno 1106,
which began to appear in the West about Middle of February,
and continued for many Days after, with such a Tail as was seen in that of 1680.
And again, in the Consulate of Lampadius and Orestes, about the Year of Christ 531,
such another Comet appeared in the West, of which Malela, perhaps an Eye-Witness,
relates that it was a great and fearful Star;
that it appeared in the West, and emitted upwards from it a long white Beam; and was seen for twenty Days.
The Interval, between this and that of 1106, is nearly equal to that between 1106 and1680, about 575 years.
And, if we reckon backward such another Period,
we shall come to the 44th Year before Christ, in which Julius Caesar was murder'd,
and in which there appear'd a very remarkable Comet, mentionnend by almost all the Historians of those Times.