"Remember I shall impatiently await your return and look for your success--I expect nothing but unqualified success from your attempt. You who have achieved so much in the past surely cannot fail me in this event. I await your agreement to attempt this voyage with confidence. I must have the herb and you are the only person who can obtain it for me." "Your friend and co-worker for the betterment of humanity, ARTEMUS TODD, M.D., Ph.D." Professor Henderson read this strange letter aloud in the evening as he and his friends were sitting before the small, clear fire of hickory logs in the big living room of the bungalow in the woods, built beside the great workshops and laboratory. With the scientist and the two boys was Andy Sudds, the old hunter, who sat cleaning his rifle, and Washington White was busy in and out of the room as he cleared away the supper and set the place in order. "Well! what do you know about that!" exclaimed Jack Darrow, always ready with a comment upon any subject. "Dr. Todd is certainly some in earnest; isn't he?" "But what a cheek he has to ask you to go on such a journey!" cried Mark. "He talks as though he expected you to start immediately for the Arctic Circle." "There would be good hunting up there in the mountains," said Andy Sudds, succinctly. "I wouldn't mind that." "An'disher chrysomela-bypunktater plant he wants," grunted Washington. "Hi, yi! ain't dat de beatenest thing? Who ebber heard of sech a plant befo'?" "Nobody but you, I guess, Washington," said the professor, quietly. "_That_ seems to be a plant of your own invention." "But, sir!" cried Mark, "you have no idea of taking this trip he suggests; have you?" "Dr. Todd has done me many a favor in the past," said Professor Henderson, thoughtfully. "Well, if you're going, count me in," said Jack, quickly. "I don't mind a summer trip to the Arctic. Say! it can't be much cooler up there than it is here right now. This fire doesn't feel bad at all." "Humph!" muttered Mark, who never was as sanguine as his chum. "This cool spell will only last a day or two here; but I understand the tops of the Endicott Range are always white." "B-r-r!" shivered Washington, at this statement. "Dis chile don't t'ink much ob such a surreptitious pedestrianation as dat, den. Don't like no cold wedder, nohow! And Buttsy don' like it, needer." "Who's Buttsy?" demanded Jack, grinning. "Why, fo' suah," said the darkey, gravely, "you knows Christopher Columbus Amerigo Vespucci George Washington Abraham Lin----" "But you wouldn't expect to take Christopher Columbus And-so-forth to Alaska with us; would you?" asked Andy Suggs. "Why not?" demanded the darkey. "He flowed to de moon in de perjectilator; didn't he? Huh! In co'se if de perfessor goes after disher chrysomela-bypunktater, I gotter go, too; and in co'se if I go, Buttsy done gotter go. Dat's as plain as de nose on yo' face, Andy."