REPORT I.

THE AGIEIGULTIIEAL ENVIRON lENT.

R. E. MASSEY, Economic Botanist.

SECTION I.

Meteorological Conditions.

Khartoum is situated on the Blue Nile near its junction with the White Nile, at an elevation of 378 metres above sea level.

The degrees of latitude and longitude are respectively Lat. 15 36' 20" N. and Lon. 32 32' 30" E.

From the banks of the river a wide expanse of arid sandy soil stretches in all directions, which for the greater part of the year is devoid of vegetation. No elevated areas occur sufficiently near to afiect the climate appreciably.

Typical desert conditions prevail from October to May with cloudless skies and high temperatures, the latter showing a large diurnal range. The winds are north-easterly, and very constant both in direction and force. The atmosphere is extremely dry.

For the remainder of the year, during the so-called rainy season, the prevailing winds are southerly, and with the change of direction humidity increases perceptibly, the temperature falls and a slight rainfall is experienced.

The meteorological observations taken at the Central Research Farm have for their object the elucidation of the relation existing between chmate and crop.

Temperature.—Except where otherwise stated, the instruments have been housed in a double-louvred screen similar to the type used throughout Egypt.

The thermometers were supplied by the Egyptian Survey Department, and are of standard pattern. The readings are therefore comparable with records taken at other stations in Egypt and the Sudan.

To permit of comparison between cultivated areas and the surrounding desert, the official readings from Khartoum are also given. The latter represent extremely arid conditions, for the screen is surrounded on three sides by desert. On the fourth side, a small garden intervenes between the screen and the river, which is distant about 900 metres. The Blue Nile and three miles of desert separate the two stations.