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Dr. Smith’s Airplane Trip

Dr. Smith was in a hurry. He had to get to the airport quickly or he would miss his flight to beautiful Aruba and a well-earned vacation. There would be no time for him to stop by the small brick office building that housed his private practice, so he decided to take his weathered but trusty doctor’s bag with him on the flight. The thought of leaving the small black leather bag that had been his partner for over three decades in the car for five days and four nights just didn’t seem right. What if someone broke into his car? The thief could have the new set of Pings his former colleagues bought him as a joke gift – a less than subtle attempt to get Dr. Smith to join their retirement group – he wasn’t planning on using them anytime soon. But there was no way a burgler was taking his doctor’s bag. You see, Dr. Smith was an old-fashioned type of doctor; he still had a doctor’s bag because he still made house calls. Besides, what if there were an emergency on the plane or on the beach? He hated the thought of not having his trusty partner with him at all times. So, after finishing his last house call, Mrs. Rothschild of 122 Madison Way, Dr. Smith made tracks to the airport and eventually to the check-in counter with some 20 minutes to spare.

Unfortunately for Dr. Smith, the polite but adamant United employee behind the counter made Dr. Smith part with more than $325 for the round trip airfare. What implement was Dr. Smith required to remove from his doctor’s bag before boarding the plane and why? Identify the specific item and the specific reason for its removal. Don’t think about items that could be used at potential weapons, because Dr. Smith would have had to give this item up even in the days before heightened airline security.