Matthew R. Christ and Grant Parker, "Herodotus presents geographical curiosity as a feature of foreign kings, particularly when they plan conquest". Olmstead characterised it as a "spying" expedition. It lasted thirty months. Soon afterwards, Darius seems to have added to his empire the lands explored by Scylax as a new province called Hinduš. It was referred to as "India" by the Greek writers. The extent of the province is not precisely known, though Herodotus's description of it as lying to the west of the desert (Thar desert) limits it to essentially Sindh (middle and lower Indus basin). Darius also commissioned the completion of the canal connecting the Nile with the Red Sea, stating in an inscription: Afterwards, oceanic communication between India and Persia as well as Egypt and Mediterranean were established and maintained for some time. Works Scylax wrote an account of his travels, perhaps entitled Periplus (Circumnavigation) and said to have been dedicated to Darius. The work has disappeared except for seven quotations by later writers. The surviving quotations indicate it was not merely a logbook, but contained accounts of people, landscape, the natural conditions and perhaps also political affairs. Scholar Klaus Karttunen believes that it might have been written in Greek, in which case it would have been among the first works to be written in Greek prose. Hekataios was influenced by the work and Herodotus knew about it, though he may not have actually seen it himself. The surviving quotations appear fabulous. One talks about Troglodytes (cave-dwellers), another about Monophthalmic (one-eyed people), yet another about Henotiktontes (people that produce only one offspring). According to Tzetzes, Scylax claimed that all these things were true and not made up. Scholar R. D. Milns states that Scylax would have reported the stories he heard from the natives, which he would have accepted in good faith. Scylax's Periplus provided the West with its first account of the easterly people and served as a model for later Greek writers. More lastingly, it gave India its name. The people of the Indus region were referred to as Hiduš or Hindush in Persian (due to sound change of *s > h from Proto-Iranian Sindhu). If Scylax wrote in the Ionic dialect of Greek, which did not pronounce initial h sounds, he would have transformed it to Indos (plural: Indoi). Their land was characterised as Indike (the adjectival form, meaning "Indian"). Herodotus uses these terms