             The Adventure of the Devil's Foot
    The next morning, the vicar ran into Holmes' place breathlessly and said, "Mr. Tregennis was murdered last night, too. The scene looked exactly the same as with the three people." Holmes was shocked and hurried to the scene immediately with Watson. The atmosphere in the room was horrible and gloomy so that people felt suffocated. A lamp was lit on the table in the middle of the room, letting off smoke. This lamp attracted Holmes' attention. For all indications showed the disaster happened at daybreak and that therefore there was no need to light the lamp. Holmes examined the lamp carefully, measured it, scraped some powder dusted onto the lamp, and put it into an envelope.
    Going back home, he made an experiment with Watson: he fetched some powder out of the envelope and laid it on a lighting lamp. After a little while, a thick fumes of musk rushed into their noses. All of a sudden, both of them felt their hair was standing up, and that their tongues stiffened. In a vision, it seemed a ghost was swinging to and fro within the smoke. The gloomy and chili terror made them want to shout, but they could not. At the dangerous moment, Watson struggled to drag Holmes, who was lying on the ground, and ran outside the room. After a while, they both gradually became awake.
 