"Gentlemen," he said, when the negro was out of earshot, "the man is a liar--quite an accomplished one. His masters could hardly have chosen a better man for the job."

The three officers and Tom looked at the major, waiting in silence for the explanation of this discovery. At this moment Mbutu, who had for some time been showing signs of great excitement, broke in impetuously:

"Black man talk bosh! All one lie. Him no slave not at all! Him big awful liar!"

"Your young man has an emphatic way of expressing himself," said the major; "you had better tell him, Tom, to hold his tongue until he is asked to speak, and in fact to leave us. But he is right. A slave who had been employed in carrying ivory for the Arabs would bear the marks of a collar and fetters. Looking at that handsome Ankoli I failed to find these marks, and suspected the man. You will see now that I framed my questions in such a way as to give him rope, and the way he acted his part and worked up the pa.s.sion was amazingly clever. But he overdid it, as they always will. What do you make of it all, Lister?"

Now in a scrimmage Captain Lister was a host in himself, but at the council-board he was not fluent. Contentedly pulling at his short brier, all he said was:

"Rummy, eh? What!"

Things had meanwhile been crystallizing in Tom's mind. The ambush had been foremost in his thoughts for many days past; possibly that was the reason why the suggestion came from him. However that may be, it was he who remarked quietly:

"D'you think the pretended slave is a confederate of the guide's, Uncle?"

The major looked dubious. He liked to see every step in the process--all the working of the sum, so to speak.

"Fadl," he said, "just order the guide Munta to step this way."

The major's orderly, a Soudanese more than six feet high, stalked into the camp square.

"Now, Mbutu," called the major, "come here; I want you to stand out of sight in the tent there till I beckon you. By the way, Tom, that dago fellow had a name, I suppose. What is it?"

"I never heard it, Uncle. Mbutu has always called him 'old master' or 'dago man' to me. What was your master's name, Mbutu?"

"Black man call him debbil, sah."

"Never mind what the black man calls him, what do the Arabs call him?

What did this guide of ours call him?"

"Call him senor, padrone; one time call him Castro, one time more call him Carvalho; him lot names too many."

"Bedad now," exclaimed the doctor, "it all comes back to me.

Carvalho!--of course, 'tis the name of the Portuguese who gave us no end of trouble in Quid Calabar ten years ago. I disremimbered'm entirely; ten years makes a terrible difference in a man, to be sure; though when I saw Tom knock him down there was something in the creature's scowl that seemed familiar. Sure an' I ought to have remimbered his b.u.mps. A desp'rate ruff'n of a fellow, Major. He came to me wance to be st.i.tched up after getting mauled in a drunken brawl, an' I got to know a thing or two about'm. Ah! an' there was wan curious affair he was mixed up in that--

"I'm afraid the story must keep, Doctor; here's the guide."

Captain Lister put down his pipe; Lieutenant Mumford lit a cigarette.

The Arab, or rather half-caste, approached confidently and saluted. The major looked up.

"Have you any reason to give," he said quietly, "why you should not be taken out and shot?"

The man stared open-mouthed at the speaker. His face appeared to turn a bronze-green, and his lips twitched. The major was watching him intently.

"I don't--I don't understand, master," he stammered at length.

"Ah! Let us begin at the beginning. Do you know one Castro, a Portuguese, who was in Kisumu for some days before we started?"

The man, with a strong effort of will, had mastered the agitation into which the major's sudden question had thrown him.

"He is going to brazen it out," said that observant officer to himself; and after the slightest perceptible pause, the Arab replied:

"I do not know him, sir."

"Very well."

He beckoned to Mbutu, who had been standing with his face concealed by the flap of the tent. The Muhima came out into the sunlight.

"Do you know this boy?"

Tom saw the Arab's eyelids quiver.

"No--I do not know him, master. I never saw him before."

Major Burnaby turned to the Muhima.

"Mbutu, is this the man?" he asked.

"Him sure nuff, sah; him gib me kiboko."

"The boy lies. I never saw him; I know nothing about him."

"Very well. I shall have to refresh your memory. Fadl, tell Sergeant Abdullah to bring up a firing-party."

There was a strained silence. The Arab looked round apprehensively as six men of the King's African Rifles came up, ordered arms, and stood rigidly at attention.

The major took his watch from his pocket and laid it on the table in front of him.

"I give you five minutes," he said. "If you do not make up your mind to tell the truth within five minutes by my watch--well, you know what'll happen."

The major glanced significantly at the line of Soudanese. He deliberately cut and lit a cigar. Captain Lister had resumed his pipe and was puffing vigorously; Lieutenant Mumford gripped the sides of his seat, and stared; while the doctor was apparently examining the Arab's anatomy with a quite professional interest. To Tom his uncle was appearing in a new light, commanding a new respect and admiration; and as to Mbutu, he was patently overawed by the stern imperturbability of "sah him uncle".

The minutes went by. The silence of the bright morning was broken only by the varied sounds of movement in the camp: the laughter of the Zanzibaris; the clash of a cook's pan; the bleat of a goat led to the slaughter.

"You have half a minute," said the major suddenly.

"I know nothing, master, nothing at all," replied the guide, his lips quivering.

There was again silence. Then the major rapped his hand on the table.

"Now!" he said. "What have you to say?"

"I know nothing about it, nothing about it!" persisted the man.

"I've no time to waste," said the major curtly, replacing his watch.

"Sergeant, take him away."

Two of the tall Soudanese laid their hands on the guide's arms. He wriggled out of their grasp and flung himself on the ground. They seized him again, a.s.sisted by their comrades; and, struggling desperately, crying continually: "I know nothing about it, know nothing about it!" he was carried away. Tom's heart was in his mouth, and Mumford had sprung up in his excitement. Captain Lister still smoked on placidly; while the major's lips were grimly set as he watched the man's contortions. He had been borne but a few yards when his writhing suddenly ceased.