midnight
She pirouetted on one toe in front of the glass . The motion exhilarated her , and , raising her white wrapper so as to get a peep at her small , pretty feet , she waltzed slowly and gracefully in front of the mirror . `` I ca n't and wo n't study to-night , '' she said again . `` I hate study , and I will not spoil my looks by burning the midnight oil . '' Suddenly she clasped her hands and the color rushed into her cheeks . `` How fortunate that I remembered ! I must write to mother this very night .