Kingozi retired again to his cot; but for a long time he could not get to sleep. Little things annoyed him. A fever owl in a thorn tree somewhere nearby called over and over again monotonously, hurriedly, without pause, without a break in rhythm. Kingozi knew that the bird would thus continue all night long, and he tried to adjust his mind to the fact, but failed. It seemed beyond human comprehension that any living creature could keep up steadily so breathless a performance. Some of the men were chatting in low voices. Ordinarily he would not have heard them at all; now they annoyed him. He stood it as long as he could, then shouted "Kalele!" at them in so fierce a tone that the human silence was dead and immediate. But this made prominent other lesser noises. Kingozi's headache was worse. He tossed and turned, but at last fell into a half-waking stupor.

He was brought to full consciousness by the entrance of Cazi Moto. He opened his eyes. It was still night--a very black night, evidently, for not a ray of light entered the tent.

"What time is it, Cazi Moto?" he asked.

"Five o'clock, bwana."

It was time to rise if a march was to be undertaken. Kingozi waited a moment impatiently.

"Why do you not light the candle?" he demanded.

"The candle is lighted, bwana" replied Cazi Moto, with a slight tone of surprise.

Kingozi reached his outspread hand across to his tin box. His fingers encountered a flame, and were slightly scorched. He lay back and closed his eyes.

"The men have struck their tents?" he asked Cazi Moto after a moment.

"Yes, bwana, all is prepared."

Then there must be a dozen little fires, and the tent must be filled with flickering reflections. Kingozi lay for some time, thinking. He could hear Cazi Moto moving about, arranging clothes and equipment. When by the sounds Kingozi knew that the task was finished and Cazi Moto about to depart, he spoke.

"We shall not make safari to-day," he said. Cazi Moto stopped.

"Bwana?"

"We shall not make safari to-day."

Cazi Moto's mind adjusted itself to this new decision. Then, without comment, he glided out to reverse all his arrangements.

Left alone Kingozi lay on his back and bent his will power to getting control of the situation.

He was blind.

At first the mere thought sent so numbing a chill through all his faculties that he needed the utmost of his fortitude to prevent an insensate and aimless panic. Gradually he gained control of this.

Then he groped for the candle. By experiment he found that at a distance of a foot or so the illumination registered. Then there was no paralysis of the nerve itself. Desperately he marshalled his unruly thoughts, striving to look back into the remote past of his student days. Fragments of knowledge came to him, but nothing on which to build a theory of what was wrong.

"It's mechanical; it's mechanical," he muttered over and over to himself, but could not seem to progress beyond this point. All he could conclude was that it was not ophthalmia or trachoma. He had seen a good deal of these two plagues of Egypt, and their symptoms were absent here. He concentrated until his mind was weary, and his will slipped. At last in despair he relaxed and in an unconscious gesture rubbed his eyes with his forefingers and thumbs. The contact brought him to with a jerk.

The eyeballs, instead of feeling soft and velvety under the lids, were as hard as marbles.

The shock of this phenomenon rang a bell in his memory. A distinct picture came to him of his classroom and old Doctor Stokes. He could fairly hear the slow, impressive voice.

"There is one symptom," the past was saying to him, "one symptom, young gentlemen, that is not always present; but when present establishes the diagnosis beyond any doubt. I refer to a peculiar hardening of the eyeball itself----"

"Glaucoma!" cried Kingozi aloud.

His thoughts, like hounds on a trail, raced off after this new scent. Desperately he tried to recollect. In snatches he captured knowledge. Of its accuracy he was sometimes in doubt; but little by little that doubt grew less. To change the figure, the latent images of his past science developed slowly, like the images on a photographic plate.

Glaucoma--a hardening, an enlarging of the pupil, a change in the shape and consistency of the iris--yes, he had it fairly well. Treatment? Let's see--an operation on the iris, delicate. That was it. Impossible, of course. But there was something else, a temporary expedient, until the surgeon could be reached--an undue expansion of the pupil----

"Why," shouted Kingozi aloud, sitting up in bed. "Pilocarpin, of course!"

What luck! He fervently blessed the shortage of phenacetin that had forced him to take pilocarpin as a sweating substitute for fever.

"Cazi Moto!" he called. Then, as the headman hurried up: "Get me the box of medicines, quick!"

He waited until he heard the little man reenter the tent.

"Place it here," he commanded. "Now go."

He groped for the case, opened it----

The bottles it contained were all of the same shape. He remembered that the pilocarpin was at the right-hand end--or was it the left? Hastily he uncorked the left-hand bottle, and was immediately reassured. It contained tablets. The right-hand bottle, on the contrary, held the typical small crystals. But a doubt assailed him. At the same end of the case were the receptacles also of the atropin and the morphia. He remembered the Leopard Woman's remarking how much alike they all were. Kingozi seemed to see plainly in his mind's eye the precise arrangement, to visualize even the exact appearance of the labels on the bottles--first the morphia, next to it the pilocarpin, and last the atropin. But while he contemplated this mental image, it shifted. The pilocarpin and atropin changed places. And this latter recollection seemed as distinct to him as the first had been.

He fingered the three bottles, his brows bent. And across his mental travail floated another thought that brought him up all standing.

Pilocarpin and atropin had exactly the opposite effect.

"Here, this won't do!" he said aloud. "If I get the wrong stuff in my eyes it will destroy them permanently."

He raised his voice for Cazi Moto.

"When Bibi-ya-chui is awake," he told the headman, "I want to see her. Tell her to come."