6 SOIL AND CLIMATE.

the devastation caused by a hurricane of this kind is beyond description. Unfortunate, indeed, is he who happens to be overtaken in the desert by one of these storms. There is no course left for him to save himself, but to throw himself with his face!

on the ground, in order to avoid suffocation by the I pressure of the atmosphere. Respiration is totally I impeded ; all the fibres are tightly contracted ; the | chest threatens to burst for want of pure air ; and a j man of rather weak constitution, overtaken by one of these hurricanes in the open air, generally succumbs. But robust men, even those in full vigour of life, feel depressed in every limb for several hours after exposure to these storms, and recover but slowly, and by degrees. Animals fly and endeavour to conceal themselves ; every creature, in fact, seeks a place of shelter. The camels on journeys indicate the storm before it breaks forth by an unsteadiness of gait, and by drooping their heads towards the ground.

A no less remarkable phenomenon is the Mirage, i. e. the appearance of seas and rivers, supposed to be observed in the middle of the desert, but which, in fact, are only represented to the eye m this deceptive manner by a rising vapour, and the reflection of the sun. The sensation is indescribable, of desciying at the distance large rivers and lakes, after having travelled for several tedious days through the desert, where nothing is to be seen but sand and heaven, as but water and sky on the high seas,