"Laugh all you want to," continued the Irishman, "but it's a fact. Why, when they were building the Yukon railroad, during the months of July and August as the men went to work, they had to send the snow plow ahead of the gang in the morning in order to break a way through the banks of mosquitoes, and sometimes they had to put two engines behind the plow--make a double-header of it." "Pretty good yarn, Magee," said the boy, "but if they're no worse than that I guess I can stand it." Here Rivers broke in. "You will do well if you do stand it," he said, "because Magee is not so very far out. You will hardly believe it, but I would rather face a country of hostile Indians than hostile mosquitoes. That little mosquito you saw to-night means hundreds to-morrow, thousands the next day, and from that until cold weather hundreds of thousands all the time. Magee isn't exaggerating much, because Baron Munchausen would find it hard to do the Alaskan mosquitoes justice, when they get busy." "Are they especially venomous, then?" the boy asked, growing serious. "No, but they are especially numerous. Many a man has gone mad on the trail because he had no protection from them. That, practically, wiped out of existence one of the largest gold-hunting parties that ever came to Alaska." "Tell us about it, Mr. Rivers," urged Roger. "Well, I will," the chief replied, "if it is only to give you a due respect for your enemies. This party of which I am speaking had landed on Kotzebue Sound, and having heard of an alleged Indian trail to the Koyukuk, somewhere near the Selawik River, and having found out beside that it was tundra and flat, they thought it would be easy traveling." Here Magee chuckled audibly at the idea of tundra being easy going. "It wasn't long," went on the chief, not noticing the interruption, "before they reached the tundra and discovered that it was scarcely as pleasant as they thought. Walking on tundra is like, is like,--tell him what it's like, Magee." "It's like walking over slippery footballs half-sunk in slime," said the Irishman promptly. "Well, that will do," said Rivers. "Any way, they were tramping over this and losing heart fast when the mosquitoes began. They had nothing with them which would serve to keep off the insects, and some of the party were stung so fearfully that a superficial form of blood poisoning set in. Others, unable to endure the torture night and day, killed themselves; others again went insane and became violent; of that large party but two returned to the coast, one who by some freak of nature was immune, and his chum, who had become half-witted by the experience." "You bet," commented the topographer, "the Alaskan mosquito is a matter to be taken very seriously."