“Quite,” replied Renstoke. “And I am sorry we had to trouble you. But I am sure you will understand why I came. The affair is so mysterious that I could not leave any possibility unexplored.” Erckmann had puzzled them all. The man was perfectly courteous and apparently quite open in his replies to their questions. None the less all sensed that he was ill at ease and that he quite certainly resented their intrusion.
Yvette, more sensitive and keenly strung than the others, shuddered violently as they left the house.
“That man is bad, all bad,” she declared vehemently. “He has the eyes of the snake.” She had put into words what all had felt, yet had been half ashamed to confess. There was something repulsively snake-like in the steady glare of Erckmann’s eyes behind the thick round glasses.
“I confess I feel like Yvette,” said Dick, “the man gave me the creeps.”
Renstoke looked grave.
“He didn’t strike me as being quite aboveboard,” he admitted. “At the same time, I don’t see what he has to conceal. All the cages were occupied and it is certain none of the animals had been loose recently, and if one had broken out there is no reason why he should not say so. But he may have another ape which he has not shown us?”
They walked a few hundred yards in silence until they had got to the bottom of the hill and approached the little burn that ran down the valley. There was no path, and as chance would have it, they deviated a few yards from the way along which they had come. They were crossing the brook when Yvette gave a slight exclamation.
“Oh, look here,” she said.
The bed of the burn was stony throughout, but at one point, at the very edge of the water was a tiny patch of sand, smooth and firm and hardly larger than a handkerchief. Yvette pointed to it.
There, sharply and clearly defined, was the unmistakable imprint of a naked, misshapen foot! It was human beyond all question. It pointed in the direction of the house they had just left, and it was dear that the barefooted walker, whoever he may have been, had stepped from the heather just on to the patch of firm sand and been carried by his next stride through and beyond the rivulet on to the heather and stones where no footprints would remain. By some strange chance that one tell-tale footprint had been left in perhaps the only square foot of ground for miles where an impression could be left!