Jack and Mark went with the old man into the middle room of the craft. There they found the old hunter and the two farm hands. None of the three had quite gotten over his fright at being suddenly carried off through the air. "Everything has turned out for the best," the inventor began. "I feared my forced start would spoil my plans, but you see I got a crew almost at the last moment. Now we will--" He was interrupted by a sudden cry from the engine room. "Help! Help!" rang out the voice of the colored man. "Hurry up an' help, Perfessor. I'm caught in some cantankerous conglomeration an' I'm bein' killed! Help! Help!" Followed by the boys and the three men the old inventor hastened aft, alarm showing on his face. CHAPTER VII HELD BY ELECTRICITY As they reached the engine room they saw a queer sight. Washington was close to the buzzing dynamo which he had started to oil. His hands grasped two large copper switches used to turn the current on and off. "Let go and come away from there!" cried Mr. Henderson. "I can't! I'se stuck fast!" yelled the negro, writhing in pain. Andy Sudds started on the jump to assist the unfortunate man. "Don't touch him!" exclaimed Mr. Henderson. "He's held fast by electricity! If you attempt to pull him away with your bare hands you'll be caught just as he is! Wait a minute!" The inventor rapidly opened a locker. From it he took out a pair of rubber gloves. Putting these on he hurried to where the negro was still squirming in pain and terror. "Help! Help!" Washington yelled. "I'm burning up!" "Wait a moment! I'll save you!" shouted the captain of the _Monarch_. The next instant he reached up, and turned off the electric current. Washington fell in a limp heap on the floor of the engine room. He was freed from the grip of the electricity that had held him as in a vise. The professor ran to a medicine closet and got a remedy which he administered to the unfortunate one. In a little while the colored man was better. He sat up, opened his eyes, which had been closed, and remarked: "Dat was a mighty close call fer dis chicken!" "What made you go near the switch?" asked Mr. Henderson. "I have warned you several times never to put both hands on a copper switch at the same time. One hand does not matter, but two make the connection." "I knows it now, Perfessor," said Washington humbly. "Then I hope you'll remember it. That applies to all of you," he went on. "If ever you have occasion to touch any electrical machinery, don't do it with both hands at the same time, if there is danger of forming a connection. Always use rubber gloves, and you'll be in no danger. Rubber is a non-conductor. Remember, Washington." "I'll recollection it on de next obstreperous occasion," promised the negro. "You must feel better when you can use your big words," said Mr. Henderson with a laugh. "Now," he continued, "I was about to give a few general instructions about the airship, when Washington interrupted us.