“Ah, I comprehend! I had forgotten the imprints which I must have left when I went down to the rock. It was dark, you understand?—and naturally I did not perceive that I was leaving traces. So that was it, Sir Clinton?”
Armadale was obviously puzzled. He turned to Mme. Laurent-Desrousseaux.
“What size of shoe do you wear, madame?”
She glanced at her neatly shod feet.
“These shoes I have bought in London a few days ago. The pointure—the size, you call it, isn’t it?—was No. 4.”
Armadale shrugged his shoulders, as though to express his disbelief.
“Measure these prints on the sand here, inspector,” Sir Clinton suggested.
Armadale drew out his tape-measure and took the dimensions of the footmarks left by Mme. Laurent-Desrousseaux.
“And the length of step also, inspector,” Sir Clinton suggested.
“They correspond with the tracks down to the rock, true enough,” the inspector admitted, when he completed his task. “But only a 3½ shoe could have made them.”
Sir Clinton laughed, though not sneeringly.
“Would you lend me one of your shoes for a moment, madame?” he asked. “You can lean on me while it’s off, so as not to put your foot on the wet sand.”
Mme. Laurent-Desrousseaux slipped off her right shoe and held it out.
“Now, inspector, there’s absolutely no deception. Look at the number stamped on it. A four, isn’t it?”
Armadale examined the shoe, and nodded affirmatively.
“Now take the shoe and press it gently on the sand alongside a right-foot print of Mme. Laurent-Desrousseaux—that one there will do. See that you get it square on the sand and make a good impression.”
The inspector knelt down and did as he was told. As he lifted the shoe again, Wendover saw a look of astonishment on his face.
“Why, they don’t correspond!” he exclaimed. “The one I’ve made just now is bigger than the other.”
“Of course,” the chief constable agreed. “Now do you see that a No. 4 shoe can make an impression smaller than itself if you happen to be walking in sand or mud? While you were hunting for people with 3½ shoes, I was turning my attention to No. 4’s. There aren’t so many in the hotel, as you know. And it so happened that I began with Mme. Laurent-Desrousseaux. She was good enough to go for a walk with me; and by counting her steps I gauged the length of her pace. It corresponded to the distance on the tracks.”
Mme. Laurent-Desrousseaux was examining Sir Clinton with obvious admiration, not wholly unmixed with a certain uneasiness.
“You seem to be very adroit, Sir Clinton,” she observed. “But what is this about the length of my pace?”
“The inspector is accustomed to our English girls, madame, who have a free-swinging walk and therefore a fairly long step. From the length of the steps on the sand he inferred that they had been made by someone who was not very tall—rather under the average height. He forgot that some of you Parisians have a different gait—more restrained, more finished, shall we say?”
“Ah, now I see!” Mme. Laurent-Desrousseaux exclaimed, not at all unsusceptible to the turn of Sir Clinton’s phrase. “You mean the difference between the cab-horse and the stepper?”
“Exactly,” Sir Clinton agreed with an impassive face.
Armadale was still puzzling over the two footprints. Mme. Laurent-Desrousseaux, evidently wearying of standing with one foot off the ground, recovered her shoe from him and slipped it on again. Sir Clinton took pity on his subordinate.
“Here’s the explanation, inspector. When you walk in sand, you put down your heel first. But as the sand’s soft, your heel goes forward and downward as you plant your foot. Then, as your body moves on, your foot begins to turn in the sand; and when you’ve come to the end of your step, your toe also is driven downwards; but instead of going forward, like your heel, it slips backward. The result is that in the impression the heel is too far forward, whilst the toe is in the rear of the true position—and that means an impression shorter than the normal. On the sand, your foot really pivots on the sole under the instep, instead of on heel and toe, as it does on hard ground. If you look at these impressions, you’ll find quite a heap of sand under the point where the instep was; whilst the heel and toe are deeply marked owing to each of them pivoting on the centre of the shoe. See it?”
The inspector knelt down, and Wendover followed his example. They had no difficulty in seeing Sir Clinton’s point.
“Of course,” the chief constable went on, “in the case of a woman’s shoe, the thing is even more exaggerated owing to the height of the heel and the sharpness of the toe. Haven’t you noticed, in tracks on the sand, how neat any woman’s prints always look? You never seem to find the impression of a clumsy foot, simply because the impression is so much smaller than the real foot. Clear enough, isn’t it?”
“You are most ingenious, Sir Clinton,” Mme. Laurent-Desrousseaux commented. “I am very glad indeed that I have not you against me.”
Sir Clinton turned the point.
“The inspector will bring you a copy of the evidence you have so kindly given us, madame, and you will do us the favour to sign it. It is a mere formality, that; but we may need you as a witness in the case, you understand?”
Rather ungraciously, Mme. Laurent-Desrousseaux agreed. It was evident that she had hoped to escape giving evidence in court.
“I do not desire to offer testimony against the young Madame Fleetwood if it could be averted,” she said frankly. “She was good to me once or twice; very gentle, very kind—not like the others in the hotel.”
The inspector shrugged his shoulders, as though the matter were out of his hands; but he made no reply.
“You will, of course, say nothing about this to anyone, madame,” Sir Clinton warned her, as they walked across the sands to the car.
At the hotel, Sir Clinton was met by a message from Cargill asking him
