Into Central Asian wilds, which lasted from March 1879 to October 1880, included the sources of the Hw: Ho, or Yellow river, till then unmapped and unknown.
There is a tradition that Timur attempted the passage of the Hindu Kush by one of the unmapped passes hereabouts, and that, having failed, he left a record of his failure engraved on a rock in the pass.
The Liberian frontier with the adjacent French possessions was defined by the Franco-Liberian treaty of 1892, but as the definition therein given was found to be very difficult of reconciliation with geographical features (for in 1892 the whole of the Liberian interior was unmapped) further negotiations were set on foot.
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