, with a crunch, Livingstone's heel went through a white
object half hidden in the long grass--a thing like an ostrich's egg.
He stooped--and his strong, bronzed face was twisted with mingled
sorrow and anger, as, looking into the face of his younger friend, he
gritted out between his clenched teeth, "The slave-raiders again!"

It was the whitening skull of an African boy.

For weeks those two Britons had driven their little steamer (the
_Asthmatic_ they called her, because of her wheezing engines) up the
Zambesi river and were now exploring its tributary the Shire.

Each morning, before they could start the ship's engines, they had
been obliged to take poles and push from between the paddles of the
wheels the dead bodies of Africans--men, women, and children--slain
bodies which had floated down from the villages that the Arab
slave-raiders had burned and sacked. Livingstone was out on the long,
bloody trail of the slaver, the trail that stretched on and on into
the heart of Africa where no white man had ever been.

This negro boy's skull, whitening on the path, was only one more
link in the long, sickening shackle-chain of slavery that girdled
down-trodden Africa.

The two men strode on. The forest path opened out to a broad clearing.
They were in an African village. But no voice was heard and no step
broke the horrible silence. It was a village of death. The sun blazed
on the charred heaps which now marked the sites of happy African
homes; the gardens were desolate and utterly destroyed. The village
was wiped out. Those who had submitted were far away, trudging through
the forest, under the lash of the slaver; those who had been too old
to walk or too brave to be taken without fight were slain.

The heart of Livingstone burned with one great resolve--he would track
this foul thing into the very heart of Africa and then blazon its
horrors to the whole world.

The two men trudged back to the river bank again. Now, with their
brown companions, they took the shallow boat that they had brought
on the deck of the _Asthmatic_, and headed still farther up the Shire
river from the Zambesi toward the unknown Highlands of Central Africa.

_Facing Spears and Arrows_

Only the sing-song chant of the Africans as they swung their paddles,
and the frightened shriek of a glittering parrot, broke the stillness
as the boat pushed northward against the river current.

The paddles flashed again, and as the boat came round a c