"Excuse me, Miss Heredith," he said. "One of the maids told me that you no longer occupied the room upstairs in the left wing, so I took the liberty of going in there to see if it was possible for the murderer to have escaped by clambering from the window of one room to another, and while I was there I found this chain. It was hanging out of a drawer of the toilet-table near the window, and as it had obviously been forgotten I thought I had better restore it to you." He held it out to her as he finished speaking, keenly watching her face for some sign of confusion or trepidation. But Miss Heredith received the chain calmly, and thanked him for returning it. Caldew was disappointed at the failure of his test, but he essayed a further shot. "I noticed a very peculiar little image among the charms on the chain," he said hesitatingly. "I have never seen anything like it before, and I couldn't help wondering where it came from." It was a clumsy trap, and he realized it, but he was too anxious to achieve his end by more subtle methods. There was nothing in Miss Heredith's calm countenance to suggest that she was alarmed or uneasy at his curiosity. She turned to Musard. "Mr. Caldew means the strange little image you gave me when you arrived, Vincent. What is it?" She held out the chain, and the explorer took it in his big brown hand. He separated the image from the other charms with his forefinger, and turned it over carelessly. "That is a tiki," he said. The explanation conveyed nothing to Caldew. "I have never heard the word before," he said. "What is a tiki?" "It is the Maori word for the creator of man, and is also taken to represent an ancestor," Musard explained. "The Maoris are to some extent ancestor worshippers, and adorn their pahs and temples with large wooden images of immense size, supposed to represent some renowned fighting ancestor. These images are worshipped as gods, and are believed to be visited by the spirits, who ascend to converse with them by the hollow roots of a pohutukawa tree, which descends into the Maori nether regions. The smaller tikis, or, more strictly speaking, hei-tiki, such as this, are carved as representations in miniature of the larger images, and are worn as neck ornaments. They are supposed to render the wearer immune from the wicked designs of evil spirits." "From what material are they carved?" said Caldew, who had followed this explanation attentively. "I have never seen anything resembling it. It seems as clear and colourless as glass, but it emits a faint greenish lustre, and there are black flecks in it." "It is nephrite, or Maori greenstone," replied Musard. "London jewellers term it New Zealand jade." "Surely this stone is not jade?" said Caldew, in some surprise. "I have seen New Zealand jade ornaments in London shops, but they were made from a dull deep greenstone, not a bit like this stone, which is clear as crystal, and has a lustre."