AN OASIS IN THE DESERT. 



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under its " protection " the peaceful Berbers who cultivate the oasis, 

 these towers were useful as posts of observation whence to descry 

 the approach of the wandering Arabs, who resort in summer to the 

 pastures of the mountains, and in winter to those of the Sahara. 



As a type of the oasis of the Desert of Erosion, let us take that 

 of Ouargla, the last which submitted to the French in South Algeria. 



A STREET IN- OUARGLA. 



It is situated in a profound hollow. In form it is elliptical, with 

 its major axis measuring about five thousand yards, and its minor 

 about three thousand. The palms are planted at the rate of ten to 

 eleven hundred a hectare (two acres) ; they attain to extraordinary 



