=Matt King=, concerning whom there has always been a mystery--a lad of splendid athletic abilities, and never-failing nerve, who has won for himself, among the boys of the Western town, the popular name of "Mile-a-minute Matt."
=Chub McReady=, sometimes called plain "Reddy," for short, on account of his fiery "thatch"--a chum of Matt, with a streak of genius for inventing things that often land the bold experimenter in trouble.
=Welcome Perkins=, a one-legged wanderer who lives with Chub and his sister while their father prospects for gold--Welcome is really a man of peace, yet he delights to imagine himself a "terror," and is forever boasting about being a "reformed road-agent."
=Dirk Hawley=, a sporting man who usually gets whatever he goes after; and being both rich and unscrupulous is reckoned a dangerous character to have for an enemy.
=Dace Perry=, a school companion of young King, who has learned to hate Matt so furiously that he is ready to go to almost any length in order to do our hero an injury.
=Tom Clipperton=, known generally as "Clip," a quarter-blood, who is very sensitive about his Indian ancestry.
=Susie McReady=, the small sister of Chub.
=Delray=, a watchman in charge of the abandoned "Bluebell" Mine.
=Jacks=, } =Bisbee=, } two ruffians in the employ of Hawley.
"Shade o' Gallopin' Dick! Say, allow me to rise an' explain that I kin ride anythin' from a hoss to a streak o' greased lightnin'. I don't take no back seat fer anythin' on hoofs, 'r wheels, 'r wings. If ye think ye kin make Eagle-eye Perkins, ex-Pirate o' the Plains, take to the cliffs an' the cactus jest by flashin' a little ole benzine push-cart onto him an' darin' him to git straddle, ye're goin' to be fooled a-plenty. Shucks! Here, hold my hat."
"Got to cl'ar decks fer action. When a man with a wooden leg goes gallivantin' around on a two-wheeled buzz-wagon, the less plunder he keeps aboard the better. Hold the hat an' hesh up about it. Which crank d'ye turn to make 'er start?"
Ed Penny, on his one-cylinder motor-cycle, had come _chug-chugging_ across the bridge over the town canal and stopped in front of the McReady home. While he was out in front, talking with Chub McReady, Welcome Perkins, the self-called reformed road-agent, had stumped out of the house and walked around the hitching-post against which Penny had leaned the machine. Welcome had snorted contemptuously. Penny had then whirled on the old man and had asked him if he thought he could ride the motor-cycle. This led to Welcome's outburst and the jerking off of his sombrero, which he handed to Chub.