"Noticed this place when out with Mr. Knowles and Gowan," he remarked, gazing down into the abyss with keen appreciation of its awful grandeur. "They told me it is the nearest that the canyon comes to the edge of the mesa, until it breaks out, thirty or forty miles down." "How--how about that 'if' you said this measurement would settle?" asked Ashton. "What's the time?" Ashton looked at his watch, frowning over the evasive reply. "It's two-ten." "I'll figure on the proposition while we eat lunch," said Blake. "I can answer you better regarding that 'if' when I have done some calculating. Luckily I climbed up to examine the rock in the gulch." He smiled quizzically at his companion. "You were right as to its being unclimbable; but I found out even more than I expected." Ashton silently took the bag from him and arranged the lunch and his canteen on a rock under a pine. The engineer figured and drew little diagrams in his fieldbook while he ate his sandwiches. Ashton had half drained the canteen on the way up the mountain. Before sitting down Blake had rinsed out his mouth and taken a few swallows of water. After eating, he started to take another drink, noticed his companion's hot dry face, and stopped after a single sip. "Guess you need it more than I do," he remarked, as he rose to his feet. "Time to start. I wish to go around and down the mountain on the other side of the gulch." "How about the--the 'if'?" inquired Ashton. "Killed," answered Blake. "There now is only one left. If that comes out the same way, Dry Mesa will have good cause to change its name." "You can tunnel through from the gulch to the canyon?" exclaimed Ashton. "Yes; and I shall do so--if Deep Canyon is not too deep." "I hope it is a thousand feet below Dry Mesa!" said Ashton. "In the circumstances," Blake replied to the fervent declaration, "I am glad to hear you say it." Ashton stared, but could detect no sarcasm in the other's smile of commendation. CHAPTER XVII A SHOT IN THE DUSK They returned to their grazing ponies, and at once started the descent of the mountain, after crossing the ravine where they had seen the wolf. Blake chose a route that brought them down into the valley above the waterhole shortly before five o'clock. They cantered the remaining distance along the wide, gravelly wash of the creek bed to the dike. Looking down from the dike, they saw that Knowles and Gowan had come up the creek and were waiting for them in company with the ladies. Ashton set spurs to his horse and dashed across above the pool, to descend the slope to the party. Blake descended on the other side, to water his horse and slake his own thirst. To Ashton's chagrin, Isobel joined Genevieve in hastening to meet the engineer. He rode down beside the two men and jumped off to follow the ladies. But Gowan sprang before him. "Hold on," he said. "Mr. Knowles wants your report." "If you'll oblige us, Lafe," added the cowman. "I'm pretty much worked up."