H ALLEY'S COMET 15 



ous historians and chroniclers of that day agree that this event was 

 announced hy a comet, which proves to have been this one of Ilalley. 

 To eclipses of the moon, April the second and September the twenty- 

 sixth of this year, assist in fixing the date securely. The second of these 

 eclipses is charged to the account of the comet itself. The return in 

 1066 has received much attention on account of its supposed connection 

 with invasion of England by William, the Norman, and with the over- 

 throw of Harold at Hastings. 



By 1456 something more like scientific activity had begun. It was 

 indeed nearly one hundred years before the publication of the immortal 

 work of Copernicus, and astronomical observers were few and far 

 between, particularly in Europe. In recent times a series of observa- 

 tions has been brought to light, made by Toscanelli in Florence. The 

 discovery was made by Celoria, in 1885, and, as may be supposed, it is 

 a most welcome addition to our data for fixing the exact circumstances 

 of this appearance. Perhaps never before or after has a comet caused 

 so much consternation as upon this occasion. Three years before, the 

 Turks under Mahomet the second had taken Constantinople and their 

 armies were pushing their conquests to the west. Many were appre- 

 hensive of the complete subjugation of Europe. Then a brilliant comet 

 appeared, the precursor, as was supposed, of further calamities, and a 

 universal panic seems to have taken possession of high and low alike. 

 Who wonders if the pope ordered the church bells to be rung every- 

 where at noon, and that all should then engage in prayer for the 

 protection against the Turks and the comet? 



1531 is one of the dates YAsed Halley in fixing the character of the 

 orbit, the other two being 1607 and 1682. This appearance is known 

 as the comet of Apian, that is, Petrus Apianus, alias Peter Bienewitz, 

 court astronomer of Charles V., and of Ferdinand I. His observa- 



IIai.i.ey's Comet (by Struve). 



