With Fire and Sword by Henryk Sienkiewicz — Read

The Poles had to raise new ramparts to render the earthworks of the Cossacks useless and make defence easier for their own reduced forces. They dug therefore all night after the storm. On this account the Cossacks were not idle. Having approached quietly in the dark night between Thursday and Friday, they threw up a second and much higher wall around the camp. All shouted at dawn, and began to fire at once, and four whole days and nights they continued firing. Much damage was done on both sides, for from both sides the best gunners emulated one another.

From time to time masses of Cossacks and the mob rushed to attack, but did not reach the ramparts. Only the musketry fire became hotter. The enemy, having strong forces, changed the divisions in action, leading some to rest and others to fight. But in the Polish camp there were no men for change; the same persons had to shoot, rush to the defence at any moment under danger of assaults, bury the dead, dig walls, and raise the ramparts for better defence. The besieged slept, or rather dozed, on the ramparts under fire, while balls were flying so thickly that every morning they could be swept from the square. For four days no one removed his clothing. The men got wet in the rain, dry in the sun, were burning in the daytime and chilled at night. During four days not one of them had anything warm in his mouth; they drank gorailka, mixing powder with it for greater strength; they gnawed cakes, and tore with their teeth hard dried meat; and all this in the midst of smoke and fire, the whistling of balls and the thunder of cannon. It was nothing to get struck on the head or body; a soldier tied a nasty bit of cloth around his bloody head and fought on. They were wonderful men -- with torn coats, rusty weapons, shattered muskets in their hands, eyes red from sleeplessness; ever on the alert, ever willing day and night, wet weather or dry; always ready for battle.