He followed the red curve with his eyes and just where this dividing line touched the rim of the hoop, another period was inscribed. Here Frobisher read:
"Eleven forty."
Frobisher looked up at Hanaud in astonishment.
"Good God!" he exclaimed, and he bent again over the map. The point where the dividing line branched off was in a valley, as he could see by the contours—yes—he had found the name now—the Val Terzon. Just before eleven o'clock Betty had stopped the car just outside Dijon, opposite a park with a big house standing back, and had asked him to tighten the strap of the tool box. They had started again exactly at eleven. Betty had taken note of the exact time—and they had stopped where the secondary road branched off and doubled back to Dijon, at the top of the hoop, at the injunction of the rim and the dividing line, exactly at eleven forty.
"This is a chart of the expedition we made to-day," he cried. "We were followed then?"
He remembered suddenly the second motor-cyclist who had come up from behind through the screen of their dust and had stopped by the side of their car to join in their conversation with the tourist.
"The motor-cyclist?" he asked, and again he got no answer.
But the motor-cyclist had not followed them all the way round. On their homeward course they had stopped to lunch in the tangled garden. There had been no sign of the man. Jim looked at the map again. He followed the red line from the junction of the two roads, round the curve of the valley, to the angle where the great National road to Paris cut across and where they had lunched. After luncheon they had continued along the National road into Dijon, whereas the red line crossed it and came back by a longer and obviously a less frequented route.
"I can't imagine why you had us followed this morning, Monsieur Hanaud," he exclaimed with some heat. "But I can tell you this. The chase was not very efficiently contrived. We didn't come home that way at all."
"I haven't an idea how you came home," Hanaud answered imperturbably. "The line on that side of the circle has nothing to do with you at all, as you can see for yourself by looking at the time marked where the line begins."