the horse-shed. While they unsaddled their horses he told them his name was Sam Daniels, yet he evinced no curiosity as to the identity of his guests, and they volunteered no information. His eyes lingered long and fondly over the exquisite lines of Satan. From behind, from the side, and in front, he viewed the stallion while Dan rubbed down the legs of his mount with a care which was most foreign to the ranges. Finally the cattleman reached out a hand toward the smoothly muscled shoulders.
It was Calder who stood nearest and he managed to strike up Daniels's extended arm and jerk him back from the region of danger.
"What'n hell is that for?" exclaimed Daniels.
"That horse is called Satan," said Calder, "and when any one save his owner touches him he lives up to his name and raises hell."
Before Daniels could answer, the light of his lantern fell upon Black Bart, hitherto half hidden by the deepening shadows of the night, but standing now at the entrance of the shed. The cattleman's teeth clicked together and he slapped his hand against his thigh in a reach for the gun which was not there.
"Look behind you," he said to Calder. "A wolf!"
He made a grab for the marshal's gun, but the latter forestalled him.
"Go easy, partner," he said, grinning, "that's only the running mate of the horse. He's not a wolf, at least not according to his owner-and as for being wild-look at that!"
Bart had stalked calmly into the shed and now lay curled up exactly beneath the feet of the stallion.
The two guests received a warmer welcome from Sam Daniels' wife when they reached the house. Their son, Buck, had been expected home for supper, but it was too late for them to delay the meal longer. Accordingly they sat down at once and the dinner was nearly over when Buck, having announced himself with a whoop as he rode up, entered, banging the door loudly behind him. He greeted the strangers with a careless wave of the hand and sat down at the table. His mother placed food silently before him. No explanations of his tardiness were asked and none were offered. The attitude of his father indicated clearly that the boy represented the earning power of the family. He was a big fellow with broad, thick wrists, and a straight black eye. When he had eaten, he broke into breezy conversation, and especially of a vicious mustang he had ridden on a bet the day before.
"Speakin' of hosses, Buck," said his father, "they's a black out in the shed right now that'd make your eyes jest nacherally pop out'n their sockets. No more'n fifteen hands, but a reg'lar picture. Must be greased lightnin'."
"I've heard talk of these streaks of greased lightnin'," said Buck, with a touch of scorn, "but I'll stack old Mike agin the best of them."
"An' there's a dog along with the hoss-a dog that's the nearest to a wolf of any I ever seen."
There was a sudden change in Buck-a change to be sensed rather than definitely noted with the eye. It was a stiffening of his body-an alertness of which he was at pains to make no show. For almost immediately he began to whistle softly, idly, his eyes roving carelessly across the wall while he tilted back in his chair. Dan dropped his hand close to the butt of his gun. Instantly, the eyes of Buck flashed down and centered on Dan for an instant of keen scrutiny. Certainly Buck had connected that mention of the black horse and the wolf-dog with a disturbing idea.
When they went to their room-a room in which there was no bed and they had to roll down their blankets on the floor-Dan opened the window and commenced to whistle one of his own wild tunes. It seemed to Calder that there was a break in that music here and there, and a few notes grouped together like a call. In a moment a shadowy figure leaped through the window, and Black Bart landed on the floor with soft padding feet.
Recovering from his start Calder cursed softly.
"What's the main idea?" he asked.
Dan made a signal for a lower tone.
"There ain't no idea," he answered,