Episode scene:

The Virginian’s old friend, Seth James, visits Shiloh on the pretext of inviting the Virginian to go hunting in the Tetons. But he is actually on the trail of two outlaws and needs the Virginian’s tracking expertise. At one point, Seth comments on the tracks he sees, to which the Virginian responds “So - How long would you say?” Seth answers him “Two days.” and the Virginian contradicts him saying “More like four - see how the edges have crumbled away? ... What'll it be - deer? bear? elk?”

Quotation from the book (Chapters 31 - 32):

At [the Virginian’s] bidding I had come eastward across Idaho, abandoning my hunting in the Saw Tooth Range to make this journey with him back through the Tetons. It was a trail known to him, and not to many other honest men. Horse Thief Pass was the name his letter gave it...
“Someone has been here since the rain,” I called to the Virginian. “Since the rain!” he exclaimed. “That’s not two days yet.” He came and examined the footprints. “A man and a hawss,” he said, frowning. “Going the same way we are.”...he touched the footprints. “They are not four hours old,” said he. “This bank’s in shadow by one o’clock, and the sun has not cooked them dusty.”

Additional comments:

1. Owen Wister loved Wyoming and made several visits there in the 1880’s and 1890’s before writing his famous book. His descriptions of the land reflect his love for it, and are quite poetic. For example, Chapter 33 opens with: Somewhere at the eastern base of the Tetons did those hoofprints disappear into a mountain sanctuary where many crooked paths have led...Snake River came into the place through canons and mournful pines and marshes, to the north, and went out at the south between formidable chasms. Every tributary to this stream rose among high peaks and ridges, and descended into the valley by well-nigh impenetrable courses...Down in the bottom was a spread of level land, broad and beautiful, with the blue and silver Tetons rising from its chain of lakes to the west, and other heights presiding over its other sides.
2. The scenery in this episode is breathtaking and the credits note that the outdoor scenes were filmed in Los Padres National Forest. However, the distance shot of the Tetons, above left, must have been added in the editing room.
3. In Echo of Another Day, the Virginian helps a posse track an outlaw who has taken Trampas hostage. Trampas comments that his friend “can track a rabbit all the way to St. Louis.”