•08 THE TROPICAL WORLD. 



genii of the waste which cannot be caught, a notion arising from 

 the fitful movements of the wind-eddy that raises them. As they 

 advance, the pious Moslem stretches out his finger, exclaiming, 

 ' Avaunt, thou ill-omened one ! ' 



Every moment the dread columns change their station, their 

 appearance, their form. Onward they move, with terrible 

 rapidity ; the sun tints them with the brilliancy of fire ; the 

 storm, whirling in and around them, cuts them into several 

 branches, reunites them, now weakens and now again strengthens 

 them ; and when, the whirlwind having spent its force, they 

 suddenly collapse, and relieve the traveller from the fear of 

 immediate danger, he 5^et must not exult too soon, for generally 

 these sandspouts are followed by the dreaded simoom. 



The temperature of the air becomes intolerably oppressive ; 

 it is sultry and enervating as before a thunder-storm. The 

 hitherto crystal transparency of the sky is veiled with a hazy 

 dimness, it is the sand of the desert whirling at a distance in 

 the atmosphere, but as yet no wind is felt. The camels, how- 

 ever, are conscious of its approach. They become restless and 

 anxious, and appear overcome by fatigue. 



And now a light hot wind arises from the south, or south- 

 west, blowing in intermittent gusts like the laborious breathing 

 of a feverish patient. 



Grradually the convulsions of the storm grow more violent 

 and frequent ; and although the sun is unable to pierce the 

 thick dust-clouds, and the shadow of the traveller is scarcely 

 visible on the ground, yet so suffocating is the heat that it 

 seems to him as if the fiercest rays of the sun were scorching 

 his brain. 



The fiery purple of the atmosphere gradually changes to a 

 leaden blackness ; the wind becomes constant ; the camels, snort- 

 ing and groaning, stretch out their necks flat upon the ground, 

 and turn their backs to the raging sand-storm. The Arabs 

 pile up the water-bags, so as to screen them from the wind and 

 diminish the surface exposed to the dry air, and wrapping 

 themselves up as closely as possible in their cloaks, seek pro- 

 tection behind chests or bales of merchandise. 



At night darkness is complete, no light or fire burns in the 

 tents, which are hardly able to resist the gusts of the simoom, 

 A deep silence reigns throughout the whole caravan, yet no one 



