Scrooge had gone to bed past 2 a.m. following his visit by the Ghost of Jacob Marley. When he awoke, he listened for the church bells to tell the time. Assuming that it was still in the early morning hours, to his surprise, the bells rang "from seven to eight, and regularly up to twelve..." The clock stopped at twelve. Scrooge believed the "preposterous" clock must be wrong: He checked his own "repeater;" it, too, read 12 o'clock. Believing that it might be 12 noon, Scrooge rushed to the window and discovered it was still dark outside.
“Why, it isn't possible,” said Scrooge, “that I can have slept through a whole day and far into another night. It isn't possible that anything has happened to the sun, and this is twelve at noon!” (Stave II)
Scrooge decided to go back to bed and await the next set of church bells. As he lay there, he remembered the Ghost's warning about a "visitation" at one o'clock. The bells rung three more times--forty-five minutes past twelve. He would remain awake for fifteen more minutes, until
... that time was passed; and, considering that he could no more go to sleep than go to Heaven, this was perhaps the wisest resolution in his power.