Such lakes (in common with all the plateau hamuns of south-west Baluchistan and Persia) change their form and extent from season to season, and many of them are impregnated with saline deposits from the underlying strata.
Afghanistan, Baluchistan, Iran or Persia, Armenia and the provinces of Asia Minor occupy this high region, with which they are nearly conterminous.
The Afghan war of 1878-80; the Russo-Afghan Boundary Commission of 1884-1885; the occupation of Gilgit and Chitral; the extension of boundaries east and north of Afghanistan, and again, between Baluchistan and Persia - these, added to the opportunities afforded by the systematic survey of Baluchistan which has been steadily progressing since 1880 - combined to produce a series of geographical maps which extend from the Oxus to the Indus, and from the Indus to the Euphrates.
With the completion of the surveys of Baluchistan and Makran much light has also been thrown on the ancient connexion between east and west; and the final settlement of the southern galuch- boundaries of Afghanistan has led to the reopening of istan and one at least of the old trade routes between Seistan Makran.
Russia, Persia, Afghanistan, Baluchistan, India and China have all revised their borders, and with the revision the political relations between these countries have acquired a new and more assured basis.
