'Hey you! Aksakal!' Rusanov wagged his finger at him. 'Stop it. You're disturbing me.' The aksakal fell silent.

Princip had even found time to learn by heart the entirety of The Mountain Wreath, Petrović-Njegos's stirring epic celebration of the selfless tyrannicide Miloš Obilić.

And when night comes, his spirits with chill feet, Winged with white mirth and noiseless mockery, Across men's pallid windows peer and fleet, And smiling silverly Draw with mute fingers on the frosted glass Quaint fairy shapes of iced witcheries, Pale flowers and glinting ferns and frigid trees And meads of mystic grass, Graven in many an austere phantasy.

Fundamental to the concept of recovering the depth by measuring defocus is the relationship between the focused and the defocused images of a scene.