A map based on native information can, of course, never hope to compete in precision with one constructed by the methods of a modern survey; but it need not be very far behind those produced by the rough-and-ready methods of the geographers of a hundred, or even fifty, years ago. Its object is to give a general idea of the district it covers, and, more especially, to give future travellers an objective, and sufficiently accurate information as to its position, to enable them to find it.
No definite system of spelling was adopted in my map. Many of the names are clearly not Arabic, but either those of the Tibbus or Bedayat, whose alphabets—if they have any—have not, so far as I know, been reduced to any system of transliteration. It was impossible to get the spelling of even the Arabic names, as all my informants were illiterate bedawin, so I have spelt them as nearly as I could phonetically. Probably the pronunciation that I heard differs from that in vogue in Sudan, so the comparison may be of use.
The information was collected as far as possible in the form of through routes, joining places that had already been more or less accurately fixed by previous travellers. The remainder of the data was then fitted into these routes, or plotted from more or less reliably fixed points on other maps.
The three main routes on which the map was based were as follows:[20]
Route I. From Tollab, in Kufara Oasis, to Bidau.
Three days south to the well of Bushara.
Four days south to Asara, or Sarra (a well only).
Six days from Asara, S.S.W., to Tikeru.
Half a day west from Tikeru to Erwully, a well.
Three days west to Guru.