At the Jinling, a comfortable hotel in Nanjing where the Gardner family spent a month in the spring of 1987, the key to our hotel room was attached to a large plastic block with the room number embossed on it. When leaving the hotel, guests were encouraged to turn in the key, either by handing it to an attendant standing behind the desk or by dropping the key into a slot. Because the key slot was rectangular and narrow, the key (with its plastic pendant) had to be carefully aligned by hand so that it would fit into the snug slot.