midnight
Tom sighed as he realized the complicated job of circuit design that lay ahead . `` This sure is going to burn some midnight oil ! '' The young inventor worked all afternoon at a furious pace , breaking off toward dinnertime to telephone his mother that he would be staying overnight at the lab . After a hasty meal , he resumed his layout job at the drawing board and by midnight had finished designing his quality analyzer sonar . Whipping off his eyeshade , Tom went into the apartment next door and stretched out to snatch a few hours ' sleep . But as usual when in the midst of an exciting new project , he was too keyed up to rest for long . Before daylight , Tom was back at his workbench ready to begin assembling the units of his new sonar gear .