Daughters of Destiny by L. Frank Baum

A solitary camel came into Mekran by the north gate, driven by a lean Baluch in a soiled yellow burnous and bearing upon its back a palanquin with curtains of faded silk. It ambled through the streets and knelt at the portals of the khan's palace, where the curtains were drawn and an aged priest cautiously descended.

Before the entrance was drawn up a company of warriors of the Tribe of Agot, who solemnly saluted the new arrival and pressed backward that he might pass within.