'IRAQ AND THE PERSIAN GULF' [‎407v] (817/862)

646
AUTHORSHIP, AUTHORITIES, AND MAPS
SURVEY AND MAPS
The basis of all Iraq maps is the field work of Survey of India detach
ments carried out during the War of 1914-1918. Before 1914 there had
been no survey; compilations only had been made from river charts and
travellers sketches. In the early stages of the war, large-scale surveys were
made of the Basra region, and afterwards, at each forward advance, new
surveys were begun from local bases and origins, to be adjusted later to
methodical triangulation gradually brought up from the Basra base. The
two main series of triangles along the Tigris and Euphrates were connected
across the intervening desert, and extensions were made at the end of the
war up the Tigris to Mosul, into Kurdistan, and up the Euphrates to link
with the work of the Egyptian Survey at Aleppo.
During the war several temporary bases were measured and astro-
latitudes were observed, but initial longitudes were approximate until
after the occupation of Baghdad, when a series of accurate longitude
operations was carried out at Fao, Baghdad, and Kermanshah, using
wireless time-signals. The results were as follows:
Baghdad (old) Residency An office of the East India Company and, later, of the British Raj, established in the provinces and regions considered part of, or under the influence of, British India. Flagstaff . . 44 0 24' 17-6"
Kermanshah Time Station . . . 47 0 04'23-9"
Fao Telegraph Office, Roof Station . . 48° 28' 55-0"
By the end of the war about ii7,3°o square miles had been surveyed in
Mesopotamia and in west and north-west Persia, on scales of half an inch
to a mile or larger. Maps in colours were published on the quarter-inch
scale by the Survey of India at Calcutta, and these gradually superseded
the provisional series of T.C. (Tigris Corps) operational maps compiled in
the field or at Baghdad. The Survey of India remained responsible for the
publication of this series until 1924) by which time the whole country,
except the western and southern deserts, a part of the mountain region,
and parts of the marsh area in southern Iraq, was covered by accurate maps.
All material, including the zinc plates, was then handed over to the War
Office, which assumed responsibility for future editions.
Unfortunately, retrenchment and the needs of economy have prevented
continuous revision. The Survey Directorate of Iraq has mostly been
engaged on large-scale surveys for land settlement and irrigation, and
these as well as new roads and railways have not been judiciously added to
the old maps, which have lost much in accuracy and clarity in consequence.
Much material also seems to have been added from reports, and some is
already out of date before the publication date of the new edition. Irriga
tion channels have been added, but the old ones which have been super
seded are often left on the maps, so that the detail of the irrigation areas has
lost much of its value. On the other hand, additional work has been carried
out, particularly in desert areas, by astro-controlled traverse surveys;
the region near the Turkish frontier was surveyed during the boundary