This desolate land, given over to stones interspersed with patches of wiry grass on which browsed some hardy sheep, resembled a disturbed ocean suddenly made solid. It was not level, but ran in long, almost regular undulations. In the trough between two of these rounded ridges the road bifurcated, the way to Bristol trending to the left, and a less important thoroughfare glancing off to the right. There was no sign-post, but a child could scarce have erred if asked to choose the track that led to a big town. Medenham, having consulted the map earlier in the day, swung to the left without hesitation. The car literally flew up the next incline, and the dark lines of trees and hedges in the distance proved that tilled land was being neared. Now he was absolutely sure that he had managed, somehow, to miss the Du Vallon--unless, indeed, its redoubtable mechanism was of a caliber he had not yet come across in the highways and byways of Europe. With him, to decide was to act. The Mercury slowed up so promptly that Mrs. Devar became alarmed again. "What is it?--a tire gone?" she cried. "No, I am on the wrong road--that is all." "But there is no other. That turning we passed was a mere lane." The car stopped where his watchful glance noted a carpet of sand left by the last shower of rain. He sprang out and examined the marks of recent traffic. Marigny's vehicle carried non-skid covers with studs arranged in peculiar groups, and their imprint was plain to be seen. But they had followed that road once only. It was impossible to determine off-hand whether they had come or gone, but, if they came from Bristol, then most certainly they had not returned. Medenham took nothing for granted. Dusk was advancing, and he must make no mistake at this stage. He ran the Mercury slowly ahead, not taking his gaze off the telltale signs. At last he found what he was looking for. The broad scars left by a heavy cart crossed the studs, and had crossed after the passage of the car. Thus he eliminated the vagaries of chance. Marigny had _not_ taken the road to Bristol--he _must_ be on the other one--since no cart was in sight. Medenham backed and turned. Mrs. Devar, of course, grew agitated. "Where are you going?" she demanded. Medenham resolved to end this farce of pretense, else he would not be answerable for the manner of his speech. "I mean to find Miss Vanrenen," he said. "Pray let that suffice for the hour. Any further explanation you may require can be given at Bristol and in her presence."