danger; he did not, however, recover his health until the lapse of ten days.
The second mishap was met by the horses. Stas, who during Kali's sickness had to fetter the horses and lead them to water, observed that they began to grow terribly lean. This could not be explained by a lack of fodder as in consequence of the rains grass shot up high and there was excellent pasturage near the ford. And yet the horses wasted away. After a few days their hair bristled, their eyes became languid, and from their nostrils a thick slime flowed. In the end they ceased to eat and instead drank eagerly, as if fever consumed them. When Kali regained his health they were merely two skeletons. But he only glanced at them and understood at once what had happened.
"Tsetse!" he said, addressing Stas. "They must die."
Stas also understood, for while in Port Said he had often heard of the African fly, called "tsetse," which is such a terrible plague in some regions that wherever it has its permanent habitat the negroes do not possess any cattle at all, and wherever, as a result of temporary favorable conditions it multiplies unexpectedly, cattle perish. A horse, ox, or donkey bitten by a tsetse wastes and dies in the course of a fortnight or even in a few days. The local animals understand the danger which threatens them, for it happens that whole herds of oxen, when they hear its hum near a waterfall, are thrown into a wild stampede and scamper in all directions.
Stas' horses were bitten; these horses and the donkey Kali now rubbed daily with some kind of plant, the odor of which resembled that of onions and which he found in the jungles. He said that the odor would drive away the tsetse, but notwithstanding this preventative remedy the horses grew thinner. Stas, with dread, thought of what
