"خريطة بلاد فارس، مع مذكرة وفهرس." [و‎‎٤] (٥٧/١٢)

memorandum on the new map of Persia.
5
to which the principles of a detailed survey by means of accurate
triangulation have been applied by British officers. There a number
and network of points and landmarks have been fixed, providing a
mathematical framework for all subsequent topography. It is not so in
Persia, No triangulation has been attempted here. The presence of
the Indo-European Telegraphic Staff has availed to determine the
longitude and latitude of important centres; but over the bulk of the
country surveys have been conducted with such instruments as inde
pendent travellers happened to possess, chiefly with plane-tables, some
times with the aid of prismatic compasses, traverses, or astronomical
observations ; the nature of the instruments employed not being stated
in every case. The result is that Persian surveys so far constitute a
sort of medley or patchwork, the same scale not being uniformly
observed, and the observations of different travellers failing to cor
respond. Scientific precision, therefore, cannot as yet be predicated of
any Persian map-making ; and future labours will doubtless disturb
several of the conclusions at which we have arrived. The utmost that
can so far be claimed even for the best Persian map is approximate
fidelity to the truth.
So much for the technical bases of our operations. I pass now to the
rules which I have observed in delineating the topography of the accom
panying map.
Mountains I have purposely refrained from indicating as darkly as
their height above the sea-level might seem to justify, for fear of encum
bering the ground, and obscuring or extruding the more necessary names
of places. Every tyro will know that the normal level of the Persian
plateau is from 3000 to 5000 feet above the sea; and that what may in
consequence appear on the map to be a plain, is commonly an elevated
upland between more or less neighbouring ranges of mountains. The
true altitude of the latter will be judged of in relation thereto.
Rivers, in such parts of their courses as have not actually been
followed or surveyed, I have indicated by broken lines ; the
number of which will illustrate the extent, to which there is still need for
the explorer’s services.
The recognised caravan routes and mule-tracks (except in the neigh
bourhood of the capital, there are no roads in Persia) have been marked