According to Chalcondyles and Phranza, the great cannon burst; an incident which, according to Ducas, was prevented by the artist's skill. It is evident that they do not speak of the same gun.
Extra note by the Rev. H. H. Milman 1782 (Written), 1845 (Revised) —Note: They speak, one of a Byzantine, one of a Turkish, gun. Von Hammer note, p. 669