"Not right away," replied the professor, without looking up from the work he was doing. "But I wish you and Jack would be around in about an hour. I am going to start the engine then, and I'll need you. If you see Washington outside send him to me."
Mark left the big room where the submarine boat had been in process of construction so long. Outside he met a boy about his own age, who was cleaning a rifle.
"How's it going, Mark?" asked this second youth, who was rather fat, and, if one could judge by his face, of a jolly disposition.
"The professor is going to try the engine in about an hour," replied Mark. "We must be on hand."
"I'll be there all right. But if there isn't anything else to do, let's shoot at a target. I'll bet I can beat you."
"Bet you can't. Wait 'till I get my gun."
"Now don't yo' boys go to disportin' yo'seves in any disproportionable anticipation ob transposin' dem molecules of lead in a contigious direction to yo' humble servant!" exclaimed a colored man, coming from behind the big shed at that moment, and seeing Mark and Jack with their rifles.
"I s'pose you mean to say, Washington," remarked Jack, "that you don't care to be shot at. Is that it?"
"Neber said nuffin truer in all yo' born days!" exclaimed Washington earnestly. "De infliction ob distress to de exterior portion ob—"
"The professor wants you," interrupted Mark, cutting off the colored man's flow of language.