In 1455, the same comet made a more memorable appearance still.  The Turks and Christians were at war, the West and the East seemed armed from head to foot—­on the point of annihilating each other.  The crusade undertaken by Pope Calixtus III. against the invading Saracens, was waged with redoubled ardor on the sudden appearance of the star with the flaming tail.  Mahomet II. took Constantinople by storm, and raised the siege of Belgrade.  But the Pope having put aside both the curse of the comet, and the abominable designs of the Mussulmans, the Christians gained the battle, and vanquished their enemies in a bloody fight.  The Angelus to the sound of bells dates from these ordinances of Calixtus III. referring to the comet.

In his poem on astronomy, Daru, of the French Academy, describes this episode in eloquent terms: 

  “Un autre Mahomet a-t-il d’un bras puissant
  Aux murs de Constantine arbore le croissant: 
  Le Danube etonne se trouble au bruit des armes,
  La Grece est dans les fers, l’Europe est en alarmes;
  Et pour comble d’horreur, l’astre au visage ardent
  De ses ailes de feu va couvrir l’Occident. 
  Au pied de ses autels, qu’il ne saurait defendre,
  Calixte, l’oeil en pleurs, le front convert de cendre,
  Conjure la comete, objet de tant d’effroi: 
  Regarde vers les cieux, pontife, et leve-toi! 
  L’astre poursuit sa course, et le fer d’Huniade
  Arrete le vainqueur, qui tombe sous Belgrade. 
  Dans les cieux cependant le globe suspendu,
  Par la loi generale a jamais retenu,
  Ignore les terreurs, l’existence de Rome,
  Et la Terre peut-etre, et jusqu’au nom de l’homme,
  De l’homme, etre credule, atome ambitieux,
  Qui tremble sous un pretre et qui lit dans les cieux.”

This ancient comet witnessed many revolutions in human history, at each of its appearances, even in its later ones, in 1682, 1759, 1835; it was also presented to the Earth under the most diverse aspects, passing through a great variety of forms, from the appearance of a curved sabre, as in 1456, to that of a misty head, as in its last visit.  Moreover, this is not an exception to the general rule, for these mysterious stars have had the gift of exercising a power on the imagination which plunged it in ecstasy or trouble.  Swords of fire, bloody crosses, flaming daggers, spears, dragons, fish, and other appearances of the same kind, were given to them in the middle ages and the Renaissance.

Comets like those of 1577 appear, moreover, to justify by their strange form the titles with which they are generally greeted.  The most serious writers were not free from this terror.  Thus, in a chapter on celestial monsters, the celebrated surgeon, Ambroise Pare, described the comet of 1528 under the most vivid and frightful colors:  “This comet was so horrible and dreadful that it engendered such great terror to the people, that they died, some with fear, others with illness.  It appeared to be of immense length, and of blood color; at its head was seen the figure of a curved arm, holding a large sword in the hand as if it wished to strike.  At the point of the sword there were three stars, and on either side was seen a great number of hatchets, knives, and swords covered with blood, amongst which were numerous hideous human faces, with bristling beards and hair.”