B. P. I.— 185. 



V. r. p. I.— 144. 



AGRICULTURE WITHOUT IRRIGATION IN 

 THE SAHARA DESERT. 



INTRODUCTION. 



In the great desert of northern Africa, stretching across in a belt 

 from southeastern Algeria to the borders of Tripoli, is the region 

 known as the " Erg." It is a land of enormous sand hills, some of 

 which reach a height of 500 feet. Chain after chain of these great 

 dunes, with knife-edge summits and steep slopes and trough-like 

 vallej^s between, extend diagonally northeast and southwest across 

 this part of the Sahara. (PI. II, fig. 1.) It is like an ocean caught 

 in a raging storm, with its huge billows rising skyward and held fixed 

 and motionless. Not a leaf nor a blade of grass, not a bowlder nor 

 a pebble mars the smoothness of the sand. Never is the least trace 

 of water to be seen on its surface. The few drops of rain that fall 

 at rare intervals are drunk up as soon as they touch the thirsty 

 ground. Pure quartz sand it is, light yellow in color and so fine of 

 grain that the least breath of air sends a little cloud of it curling olf 

 the sharp crests of the ridges. A^'lien a hard w4nd blows the air is 

 filled with it, the sun is blotted out at noonday, and the traveler can 

 hardly see his horse's head in front of him. The sharp-cornered 

 particles of sand sting his face and blind and bewilder him. The 

 vague tracks of camels and donkeys, the only roads through this 

 wilderness, are quickly covered up, all landmarks disappear, and 

 without an experienced guide one is sure to be hopelessly lost. 



It is a desolate and unfriendly landscape, yet at times not without 

 a weird beauty of its own. When the sun is high the glare is blind- 

 ing and there is little to attract one in the scene. But in the early 

 morning and the late evening the sand assumes a golden color, and 

 the dense black shadows cast by the dunes bring out their contours 

 in sharp relief. Then their surface is seen to be modeled by series 

 of delicate ripple marks left by the wind, and one finds it hard to 

 believe that when he climbs the next high ridge he will not see the 

 ocean at his feet. 



