"No, sah! Don't yo' believe anyt'ing like dat!" exclaimed the colored man. "I know dis airship. I helped build it, an' it's de strongest one de perfesser eber made. A comet won't be one, two, six wid it. We'll jest knock a piece of his tail off, at's what we'll do. I don't laik comets. Dey allers brings bad luck. Onct, when I was a young feller, I had a ten-dollar gold piece. Dat same year a comet was observed, an' de fust t'ing I knowed somebody done up an' stole mah ten-dollar gold piece. Comets brings bad luck, an' I knows it; Golly! I want t' see one ob 'em busted all t' pieces." "I guess you don't appreciate the danger," said Jack gravely, as he followed Professor Henderson back to the pilot room, where the two scientists began to consult. "We have decided on a plan, Mr. Henderson and myself," said Mr. Roumann. "The fact that so little is certainly known concerning comets makes it difficult to know what to do. We might keep on our course and come to no harm, merely pawing through a gaseous mass which makes up the comet's tail. But there is a danger that we might strike the solid head of it, for that the head is solid, and of a glowing, fiery mass, which gives off a train of sparks, is my belief. To collide with a fiery ball, larger than the sun, would indeed be terrible. So we have decided to try to pass through the less dense part the tail of the comet." "Can't we steer to one side, or above or below the comet?" asked Jack. "Impossible," replied Mr. Roumann. "We have made some calculations, and have ascertained that this is Donati's comet--the one of 1858--and the head of it is two hundred and fifty thousand miles in diameter. The tail is many millions of miles long, and as many thick. To pass entirely beyond it would consume much time. In fact, we could not move quickly enough to escape it, as we are now being attracted out of our course toward the comet." "How far off is it now?" asked Mark. "About seven hundred and twenty thousand miles." "Then we'll be up to it in about two hours," went on Mark, making a rapid calculation. "I only hope we don't get into it, as well as up to it," commented Jack. "We all do," observed Mr. Henderson. "But now, boys, we are going to do our best to escape. Mr. Roumann will remain in the pilot house to steer the projectile, while you and I will attend to the Etherium, motor." "Try and see if you can get any more speed out of it," advised the German. "Use the accelerator plates, as I instructed you. Perhaps we can pass so quickly through the gaseous tail, or a portion of it, that we shall not be harmed." "Even if it blazes?" asked Jack. "Even if it blazes. The gas between the two shells of our projectile will absorb an enormous quantity of heat. It is our only hope."