He closed one of them as he spoke, and the powerful little electric motors began to hum, forcing forward the piston attached to the tank connected to the hollow rods. Steadily the little motors hummed, and the tank emptied through the rods into the body of the giant cephalopod. "I hope the stuff works fast," groaned the doctor as they approached closer to the giant maw. "I never tried giving an octopus a hypodermic injection of prussic acid before, but it ought to do the business. There's enough acid there to kill half New York City." * * * * * Carnes blanched as the ball approached the mouth. One by one the arms unwound until only one was holding them and the jaws opened wider. They were almost in them when the motion stopped. They could feel a shudder run through the arm which held them. For a moment the arm alternately expanded and contracted, almost releasing them only to clutch them again. Another arm came from the depths and whipped about the ball, and again the vitrilene groaned at the pressure which was applied. The arms were suddenly withdrawn and the ball started to sink. "Drop the lead, Carnes!" cried the doctor. With the aid of the detective he operated the electric catches which held the huge mass of lead to the bottom, and the sphere shot up through the water like a rocket. It leaped clear of the water and fell back with a splash. A half mile away the _Minneconsin_ was swinging in a wide circle to head back toward them. They turned their gaze toward the shore. As they looked a giant arm shot a hundred yards up into the air, twisting and writhing frantically. It disappeared, and another, and then half a dozen flashed into the air. The arms dipped below the surface. A huge black body reared its bulk free from the water for a moment, and the sea boiled as though in a violent storm. The body sank and again the arms were thrown up, twisting and turning like a half dozen huge snakes. The whole creature sank below the waves and the ball tossed back and forth, often buried under tons of water and once tossed thirty feet into the air by the huge waves. * * * * * A momentary lull came in the waves. Carnes gave a cry of astonishment and pointed toward the shore. With an effort, Dr. Bird twisted himself in his lashing and looked in that direction. The huge body had again come to the surface, and three of the arms were towering into the air. Grasped in them was a long, black, cigar-shaped object. As they watched the object was torn into two parts and the fragments crushed by the enormous power of the octopus. Again the arms writhed in torment, and then they stiffened out. For a moment they towered in the air and then slowly sank below the surface of the sea.