In the second volume of his Byzantine trilogy (Byzantium: The Apogee at 350-51), John Julius Norwich contends that August 26th can be definitively identified as the date of the fateful Byzantine defeat by the Seljuk Turks on the plains some eight miles southeast of the city of Manzikert. Norwich cites a work by Alfred Friendly, The Dreadful Day: The Battle of Manzikert, 1071, as the basis for his confident assertion. Friendly based his conclusion on an account by a Byzantine officer who was present to the effect that the Tuesday and Wednesday nights before the Friday on which the battle was fought had been moonless, and the astronomical records indicate that Friday, August 26th was the only date that month that would have been so closely preceded by two moonless nights. However, other historians continue to believe that August 19th was actually "the dreadful day."