"Are you all ready, Tom?""All ready, Mr. Sharp," replied a young man, who was stationed near some complicated apparatus, while the questioner, a dark man, with a nervous mann...

 "Are you all ready, Tom?""All ready, Mr. Sharp," replied a young man, who was stationed near some complicated apparatus, while the questioner, a dark man, with a nervous manner, leaned over a large tank."I'm going to turn on the gas now," went on the man. "Look out for yourself. I'm not sure what may happen."