“Smoke?” he asked.

“I use tobacco in no form,” said the doctor.

The cowboy stared with such fixity that the match burned down to his fingertips and singed them before he had lighted his cigarette.

“’S that a fact?” he queried when his astonishment found utterance.  “What d’you do to kill time?  Well, I been thinking about knocking off the stuff for a while.  Mame gets sore at me for having my fingers all stained up with nicotine like this.”

He extended his hand, the first and second fingers of which were painted a bright yellow.

“Soap won’t take it off,” he remarked.

“A popular but inexcusable error,” said the doctor.  “It is the tarry by-products of tobacco which cause that stain.  Nicotine itself, of course, is a volatile alkaloid base of which there is only the merest trace in tobacco.  It is one of the deadliest of nerve poisons and is quite colourless.  There is enough of that stain upon your fingers—­if it were nicotine—­to kill a dozen men.”

“The hell you say!”

“Nevertheless, it is an indubitable fact.  A lump of nicotine the size of the head of a pin placed on the tongue of a horse will kill the beast instantly.”

The cowpuncher pushed back his hat and scratched his head.

“This is worth knowin’,” he said, “but I’m some glad that Mame ain’t heard it.”

“Concerning the Cumberlands,” said the doctor, “I—­”

“Concerning the Cumberlands,” repeated the cattleman, “it’s best to leave ’em to their own concerns.”  And he started to turn away, but the thirst for knowledge was dry in the throat of the doctor.

“Do I understand,” he insisted, “that there is some mystery connected with them?”

“From me,” replied the other, “you understand nothin’.”  And he lumbered down the steps and away.

Be it understood that there was nothing of the gossip in Randall Byrne, but now he was pardonably excited and perceiving the tall form of Hank Dwight in the doorway he approached his host.

“Mr. Dwight,” he said, “I am about to go to the Cumberland ranch.  I gather that there is something of an unusual nature concerning them.”

“There is,” admitted Hank Dwight.

“Can you tell me what it is?”

“I can.”

“Good!” said the doctor, and he almost smiled.  “It is always well to know the background of a case which has to do with mental states.  Now, just what do you know?”

“I know—­” began the proprietor, and then paused and eyed his guest dubiously.  “I know,” he continued, “a story.”

“Yes?”

“Yes, about a man and a hoss and a dog.”

“The approach seems not quite obvious, but I shall be glad to hear it.”

There was a pause.

“Words,” said the host, at length, “is worse’n bullets.  You never know what they’ll hit.”

“But the story?” persisted Randall Byrne.

“That story,” said Hank Dwight, “I may tell to my son before I die.”