“One of my subjects is Prothero’s brother-in-law, or rather, half-brother to Mrs. Prothero, her own father having been a blameless carpenter, and lives in the flat overhead. These flats are just tiny dwelling places consisting of two rooms and a kitchen. The builders of Lambeth tenements do not allow for the luxury of a bathroom. In this way I came to meet Mrs. Prothero whilst overcoming the reluctance of her brother to talk about himself.”
“And you met Prothero, too, I presume,” said Manfred patiently.
“No, I didn’t meet him, except by accident. He passed on the stairs and I saw him give me a swift glance. His face was in the shadow and I did not recognise him until our second meeting, which was today. He followed me home. As a matter of fact,” he added, “I have an idea that he followed me yesterday, and only came today to confirm my place of residence.”
“You’re a rum fellow,” said Manfred.
“Maybe I’ll be rummer,” smiled Leon. “Everything depends now,” he said thoughtfully, “upon whether Prothero thinks that I recognised him. If he does—”
Leon shrugged his shoulders.
“Not for the first time have I fenced with death and overcome him,” he said lightly.
Manfred was not deceived by the flippancy of his friend’s tone.
“As bad as that, eh?” he said, “and more dangerous for him, I think,” he added quietly. “I do not like the idea of killing a man because he has recognised us—that course does not seem to fit in with my conception of justice.”
“Exactly,” said Leon briskly, “and there will be no need, I think. Unless, of course—” he paused.
“Unless what?” asked Manfred.
“Unless Prothero really does love his wife, in which case it may be a very serious business.”
The next morning he strolled into Manfred’s bedroom carrying the cup of tea which the servant usually brought, and George stared up at him in amazement.
“What is the matter with you, Leon, haven’t you been to bed?”
Leon Gonsalez was dressed in what he called his “pyjama outfit”—a grey flannel coat and trousers, belted at the waist, a silk shirt open at the neck and a pair of light slippers constituted his attire, and Manfred, who associated this costume with all-night studies, was not astonished when Leon shook his head.
“I have been sitting in the dining-room, smoking the pipe of peace,” he said.
“All night?” said Manfred in surprise. “I woke up in the middle of the night and I saw no light.”
“I sat in the dark,” admitted Leon. “I wanted to hear things.”
Manfred stirred his tea thoughtfully. “Is it as bad as that? Did you expect—”
Leon smiled.
“I didn’t expect what I got,” he said. “Will you do me a favour, my dear George?”
“What is your favour?”
“I want you not to speak of Mr. Prothero for the rest of the day. Rather, I wish you to discuss purely scientific and agricultural matters, as becomes an honest Andalusian farmer, and moreover to speak in Spanish.”
Manfred frowned.
“Why?” and then: “I’m sorry, I can’t get out of the habit of being mystified, you know, Leon. Spanish and agriculture it shall be, and no reference whatever to Prothero.”
Leon was very earnest and Manfred nodded and swung out of bed.
“May I talk of taking a bath?” he asked sardonically.
Nothing particularly interesting happened that day. Once Manfred was on the point of referring to Leon’s experience, and divining the drift of his thought, Leon raised a warning finger.
Gonsalez could talk about crime, and did. He talked of its more scientific aspects and laid particular stress upon his discovery of the colour-blind criminal. But of Mr. Prothero he said no word.
After they had dined that night, Leon went out of the flat and presently returned.
“Thank heaven we can now talk without thinking,” he said.
He pulled a chair to the wall and mounted it nimbly. Above his head was a tiny ventilator fastened to the wall with screws. Humming a little tune he turned a screwdriver deftly and lifted the little grille from its socket, Manfred watching him gravely.
“Here it is,” said Leon. “Pull up a chair, George.”
“It” proved to be a small flat brown box four inches by four in the centre of which was a black vulcanite depression.
“Do you recognise him?” said Leon. “He is the detectaphone—in other words a telephone receiver fitted with a microphonic attachment.”
“Has somebody been listening to all we’ve been saying?”
Leon nodded.
“The gentleman upstairs has had a dull and dreary day. Admitting that he speaks Spanish, and that I have said nothing which has not illuminated that branch of science which is my particular hobby,” he added modestly, “he must have been terribly bored.”
“But—” began Manfred.
“He is out now,” said Gonsalez. “But to make perfectly sure—”
With deft fingers he detached one of the wires by which the box was suspended in the ventilator shaft.
“Mr. Prothero came last night,” he explained. “He took the room upstairs, and particularly asked for it. This I learnt from the head waiter—he adores me because I give him exactly three times the tip which he gets from other residents in these service flats, and because I tip him three times as often. I didn’t exactly know what Prothero’s game was, until I heard the tap-tap of the microphone coming down the shaft.”
He was busy re-fixing the grille of the ventilator—presently he jumped down.
“Would you like to come to Lambeth today? I do not think there is much chance of our meeting Mr. Prothero. On the other hand, we shall see Mrs. Prothero shopping at eleven o’clock in the London Road, for she is a methodical lady.”
“Why do you want me to see her?” asked Manfred.
He was not usually allowed to see the workings of any of Leon’s schemes until the dramatic denouement, which was meat and drink to him, was near at hand.
“I want you, with your wide knowledge of human nature, to tell me whether she is the type of woman for
