They were engaged in an earnest conversation, heedless of everything about them, when the distant cry of a camel driver sounded on the still air.

Both of the men started and looked at each other in surprise. One of them said:

"A caravan at the gate at this time of day!" for it was several hours past mid-day and a caravan, in the ordinary course of things, reaches a city gate during the night or very early in the morning.

Arabia was seeing troubled times, and every one was on the alert for anything out of the accepted rule.

The camel-driver's cry was repeated. The first speaker remarked:

"They have left the burdened camels at the Moabede gate and are entering the city."

With an anxious look upon his face the elder of the two replied, "Either they have been hard pressed by an enemy or it is important news which brings them over the desert in such haste, in this insufferable heat."

The two men were evidently of great importance in the holy city. They were surrounded by powerful black slaves, who had all that they could do to keep the passers-by from pressing too close upon the elder man, in a desire to touch the hem of his garment. Many, in passing, knelt and touched their foreheads to the ground. Thus they waited the coming caravan.

The first camel of an important caravan is led by a man who walks before it, through the narrow streets of a city, and his cry is to warn the crowd to clear the way; there being no sidewalks, and, indeed,, but very little street.

"There it comes," said the younger of the two, as the long line of drowsy camels appeared, swinging, swinging, swinging along the narrow street.

"Led by a white camel," added the elder, and they both looked down the street.

The lead-camel was larger than the rest—much larger, and very much lighter colored; a sort of dingy white, like a sheep before shearing. The chief of the caravan sat upon his back, as unmindful of everything as though he were still upon the trackless sand.

It is not impossible that the sheik was really sleeping, and unconsciously grasping his ugly lance, while his Damascus blade hung ready by his side.

He roused in a moment, however, for with many a grunt and groan the great, ungainly, and yet very stately, ships of the desert came slowly and drowsily to anchor in the court before the Caaba.

"Haji,"  a naked little urchin muttered, looking up from his play; but he should have known better. Haji  means pilgrims, and these were no pilgrims.

There are seasons when this city is one mass of humanity. Haji by hundreds and thousands throng the narrow streets, but these are Bedouins of the desert, bound upon some other mission than worshiping before the Caaba, kissing the Black Stone, or drinking the holy water of Zemzem.

The leader of the white camel gave a peculiar pull to the rope hanging over his shoulder, attached to the animal's bridle, and uttered a short, sharp word of command.

Slowly, very slowly, the dignified, dingy creature, towering high above him, acknowledged the receipt of the order, but he gave no evidence that he was making any arrangements to obey.

His response was simply a deliberate grunt and a weird and melancholy wail that came gurgling out of his long, twisting throat. He would not have hurried himself one atom, even for the sheik upon his back.

A white camel is to the Arab what a white buffalo is to the Indian and a white elephant to the Ceylonese, and he fully appreciates his importance.

He deliberately turned his woolly head quite about till his great brown eyes, with the drooping lids almost closed over them, could most conveniently look back along the line of lank, inferior camels, and gaunt and weather-beaten dromedaries, which had patiently followed him, day after day, to the temple court of immortal Mecca.

He was so long about it that the leader repeated the command and very slowly the camel brought his head back again, till his languid eyes looked drowsily down, in a sort of scornful charity, upon the insignificant mortal at the other end of his halter.

He had stood in the court of Mecca long before that man was born and would guide caravans to the same spot long after he was buried and forgotten.

"You may be in haste, but I am not," he seemed to say, and dreamily turned his eyes toward the black-curtained Caaba, as if to see how it had fared since his last visit.

That Caaba, the Holy of Holies of the Mussulman, is the most revered and possibly the most venerable of all the sacred buildings on the earth; but the gentle, wistful eyes of the white camel were more practically drawn toward two or three date-palm-trees then growing beside it. When he had satisfied himself that the only green thing in sight was quite beyond his reach, he deliberately lowered his head, changed his position a little, and with another grunt and another melancholy wail sank upon his knees, then upon his haunches. With a deep sigh he lifted his head again still high above the head of his driver, and his drowsy eyes seemed saying to him:

"Poor man! I kept you waiting, didn't I?"

Then he quickly turned his head to the opposite side, deliberately poking his nose into the passing throng, till, with a grunt of recognition, it touched the garment of one who was hurrying on among the crowd.

It was evidently a Bedouin, but the wings of his turban were drawn together in front, so that no one could see his face. He responded to the greeting of the white camel, however, by laying his hand upon the creature's nose as he passed. It was a motion which no one noticed, and a moment later he was out of sight.

He was following a boy who had led him directly to the arch, where the boy paused, pointed to the elder of the two men standing there, briefly observing:

"It is he."

The Bedouin paused for a moment, as if struggling to collect his thoughts, then hurrying forward was the next to prostrate himself before the venerable man. As he rose he handed him a package, simply observing:

"A message to the Caliph Omar."

The great caliph quickly broke the seal and read; then, turning to the bearer, asked sharply, "And who art thou?"

"I am Kanana, son of the sheik of the Beni Sads," replied the Bedouin boy, letting the wings of his turban fall apart that Omar might see his face.

"A beardless youth!" exclaimed the caliph. "And dost thou know aught of the import of this letter?"

Kanana repeated the dying words of the Arab soldier, which had so often escaped his lips as he urged his weary feet toward Mecca.

'Tis even so," replied the caliph. "And how came living man to trust a boy like you to come alone, through the streets of Mecca, with such an errand?"

"I came alone with the letter from the oasis at Mount Hor," replied Kanana, straightening himself up, with very pardonable pride, before the astonished eyes of the great caliph.

Then he related, briefly, how the letter came into his keeping, and the dangers and escapes of the three long weeks during which he carried it in his bosom; each rising and setting sun finding it a little nearer to its destination.

"Thou art a brave youth," said the caliph, "a worthy son of the Terror of the Desert. Would to Allah that every Arab had thy heart, and Heraclius himself, with all the world behind him, could not move the Faithful from their desert sands. And they shall not be moved! No! By the beard of the Prophet, they shall not be moved. Hear me, my son; I will see more of thee. This is no place for conversation, where the wind bloweth into what ears it listeth. One of my slaves shall conduct you to my house. There I will meet you presently. Go, and Allah go with you."

Indicating the slave who should take Kanana in charge, the Caliph Omar turned abruptly away and showed the letter to the man with whom he had been conversing.