"Merely press this lever," and the scientist showed them where there was one in the handle of the steel rod. "As soon as that is pressed, it admits a liquid to the chemicals and the oxygen gas is formed, rising all around you, like a protecting vapor. After that it is automatic."
"How long will the supply of chemical last?" inquired Jack.
"Each one is calculated to give out gas for nearly two weeks," was the reply; "possibly for a little longer. But come, I want to see how they work. Here is your life-torch, Professor Henderson, and there is one for you, too, Andy, and Washington."
"'Scuse me!" exclaimed the colored man hastily, as he started back toward the kitchen.
"Why, what's the matter?" asked Jack. "Don't you want to go out, and walk around the moon, and pick up diamonds?"
"Diamonds am all right," answered Washington, "but I jest done fo'got dat I ain't fed my Shanghai rooster to-day, an' I 'spects he's mighty hungry. You folks go on out an' pick up a few obde sparklers, an' when I gits de Shanghai fed I'll prognosticate myse'f inter conjunction wif yo' all."
"You mean you'll join us?" asked Mark.
"Dat's what I means, suah."
"Why, I do believe Washington's afraid!" cried Jack jokingly.
"Askeered! Who's afraid?" retorted the colored man boldly. "Didn't I done tole yo' dat I got t' feed my rooster? Heah him crowin' now? Yo' all go 'long, an' I'll meet yo' later," and with that Washington disappeared quickly.