Read "Tom Swift and His Airline Express" by Victor Appleton online for free on Textopian. Full text with search, annotations, highlights, and AI-powered reading aids.
Immediately after receiving the mysterious message from Tom, a message that seemed to come out of the air, Ned Newton made a frantic effort to get the operator at central to trace the call. But if one has ever tried to do this he knows how difficult it is. Unless one can give the telephone number of the party to whom he has been talking, and who made the call, if one is cut off there is little chance of the communication being re-established. Ned found this out to his sorrow.
"What is his number? " asked the telephone girl in a matter-of-fact way.