In fact the ancient chroniclers always associated the appearance of a comet with some terrestrial event, which it was not difficult to do, seeing that critical situations were at all times existing in some one country or other where the comet would be visible, and probably those which could not be connected with any were not thought worthy of being recorded. It is well known that the year 1000 A.D. was for a long time predicted to be the end of the world. In this year the astronomers and chroniclers registered the fall of an enormous burning meteor and the appearance of a comet. Pingre says: "On the 19th of the calends of January"--that is the 14th of December--"the heavens being dark, a kind of burning sword fell to the earth, leaving behind it a long train of light. Its brilliancy was such that it frightened not only those who were in the fields, but even those who were shut up in their houses. This great opening in the heavens was gradually closed, and then was seen the figure of a dragon, whose feet were blue, and whose head kept continually increasing. A comet having appeared at the same time as this chasm, or meteor, they were confounded." This relation is given in the chronicles of Seigbert in Hermann Corner, in the Chronique de Tours, in Albert Casin, and other historians of the time. Bodin, resuscitating an idea of Democritus, wrote that the comets were the souls of illustrious personages, who, after having lived on the earth a long series of centuries, and being ready at last to pass away, were carried in a kind of triumph to heaven. For this reason, famine, epidemics, and civil wars followed on the apparition of comets, the towns and their inhabitants finding themselves then deprived of the help of the illustrious souls who had laboured to appease their intestinal feuds. One of the comets of the middle ages which made the greatest impression on the minds of the people was that which appeared during Holy Week of the year 837, and frightened Louis the Debonnaire. The first morning of its appearance he sent for his astrologer. "Go," he said, "on to the terrace of the palace, and come back again immediately and tell me what you have seen, for I have not seen that star before, and you have not shown it to me; but I know that this sign is a comet: it announces a change of reign and the death of a prince." The son of Charlemagne having taken counsel with his bench of bishops, was convinced that the comet was a notice sent from heaven expressly for him. He passed the nights in prayer, and gave large donations to the monasteries, and finally had a number of masses performed out of fear for himself and forethought for the Church committed to his care. The comet, however, was a very inoffensive one, being none other than that known as Halley's comet, which returned in 1835. While they were being thus frightened in France, the Chinese were observing it astronomically.