Four o'clock
Occasionally a sharp crack announced that the mill wheel had been hit . The soldiers in the interior were careful of their shots ; they fired only when they could take aim . From time to time the captain consulted his watch . As a ball broke a shutter and plowed into the ceiling he said to himself : `` Four o'clock . We shall never be able to hold out ! '' Little by little the terrible fusillade weakened the old mill . A shutter fell into the water , pierced like a bit of lace , and it was necessary to replace it with a mattress .