wood sawn in two, with holes cut large enough to enclose
the neck of a slave, and the two sides of the log afterwards securely
fastened again, thereby yoking together a row of these unfortunate
beings. Every year, out of five hundred thousand or more slaves, at
least half the number perished.. The markets for the slaves were the
cities of the Muhammedans all through North Africa, Syria, Turkey, and
Persia. The death-dealing hardships to the slaves were for the most part
endured on the long journey to Cairo, or, when the trade was suppressed
there, to points north of the Sudan, such as Tripoli, or certain ports
on the Red Sea. Those who were hardy enough to reach the slave-markets
were usually well treated by their Muhammedan masters. During the time
of Baker Pasha's administration, while he was pursuing the slave-traders
and establishing Egyptian outposts, the whole course of the Nile from
the Great Lakes became well known to the civilised world, though after
this period Baker Pasha did not make any further voyages of discovery
into unknown parts.

During the years of 1859 and 1860, an adventurous Dutch lady of fortune,
Miss Alexandrine Tinne, journeyed up the Nile as far as Gondokoro, and
in 1861 she commenced to organise a daring expedition to find the source
of the Bahr-el-Ghazel, and explore the territory between the Nile basin
and Lake Chad. She started from Khartum, and ascended the Bahr-el-Ghazel
as far as the affluent Bahr-el-Hamad. She then crossed overland as far
as the Jur and Kosango Rivers, and reached the mountains on the outlying
districts of the Nyam-Nyam country. Here the members of the expedition
suffered from black-water fever, and only with the greatest difficulty
were they able to return to Khartum, where they arrived in July, 1864.
In 1868 Miss Tinne, nothing-daunted, started for Lake Chad from Tripoli,
with the intention of closing in upon the Nile from the eastern sources
of the affluents of the Bahr-el-Ghazel. On reaching Wadi-Aberjong,
however, this brave-hearted woman was waylaid by the fierce Tuaregs, and
was beheaded August 1, 1868.

In the sixties, Georg Schweinfurth, a native of Riga, in the Baltic
provinces of Russia, set out to explore Nubia, Upper Egypt, and
Abyssinia for botanical purposes. Subsequently the Royal Academy of
Science in Berlin equipped him for an expedition to explore the region
of the Bahr-el-Ghazel. He entered the Sudan by Suakin on the Red Sea,
and crossed the desert