"Try the next," suggested Craige. The second drawer proved equally unproductive of result, and it was with growing discouragement that they went through the next three and found them also uninteresting. On pulling out the last drawer Kitty found it arranged as a writing desk. "I have seen this kind before," Rodgers felt along the front of the drawer; there was a faint click and the front woodwork swung aside, disclosing an inside drawer. Kitty slipped the key she was carrying into the lock. It turned with a slight squeaking sound, showing the need of oil, and Kitty drew open the drawer. Inside it lay another brass key also tagged. "What does it say?" she asked as Rodgers picked it up. He read: This key unlocks the lower left hand drawer of the sideboard in the dining room. "Is that your aunt's handwriting?" "Yes." Kitty looked as mystified as she felt. "Shall we go downstairs and look in the sideboard?" "Of course." As he spoke, Craige started for the door. It took them but a few minutes to reach the dining room, and it was with a sense of rising excitement that Kitty unlocked the "lower left hand drawer" of the sideboard. "Good gracious! Another key!" she gasped, and held it up so that both men could read the tag tied to it. The message ran: This key unlocks the linen trunk in the attic. "Upon my word your aunt outdid herself!" exclaimed Craige. "Come, Kitty, as long as we have started this investigation, we must complete it." Not having anticipated having to return to the top of the house, Rodgers had carefully put out all the lights, and relighting the gas jets delayed them somewhat. Kitty's candle had almost burned itself out when they entered the cold and unfriendly attic. No gas pipes had been placed there, and Rodgers was thankful that his electric torch, which he carried when motoring at night, was in his pocket. By its rays Kitty recognized the old-fashioned brass-bound hair trunk in which her aunt had kept some precious pieces of hand woven linen. Crouching down on the floor with Rodgers holding his torch so that she could see the best, Kitty turned the key in the lock and threw back the lid of the trunk. On the spotless white linen lay a small brass key with a tag twice its size. The message it bore read: This key unlocks the case of the Gila monster. "The case of the Gila monster," repeated Rodgers. "What did your aunt mean?" "I know!" Kitty clapped her hands. "Ben Potter spent the summer with Aunt Susan two years ago and he left one of his cases here. It contains the plaster cast of a Gila monster." "And where is the case?" asked Craige. "In the library." "Then let us go there at once. You will catch cold up in this icy place, Kitty." Observing that she was shivering, Craige closed the trunk with a resounding bang, drew out the key, and preceded them out of the attic.