DESCRIPTIONS OF EGYPT. 
109 
without any alteration of weather ensuing. The 
phenomena of the winds, so variable in our cli- 
mate, are in Egypt regularly periodical. In point 
both of duration and strength, the northerly wind 
predominates. As it blows about nine months in 
the year, the branches of the trees, and the trunks 
themselves, when unsheltered, assume its direction. 
It continues with little intermission from the end 
of May till the end of September. About the end 
of September, when the sun repasses the line, the 
wind returns to the east, where it fluctuates till 
November, when the northerly winds again pre- 
vail. About the end of February, the winds 
assume a southerly direction, and fluctuate exceed- 
ingly till the close of April, when the east wind 
begins to predominate. The southerly winds are 
the most inconstant, as well as pernicious ; tra- 
versing the arid sands of Africa, uninterrupted by 
rivulets, lakes, or forests, they arrive in Egypt 
fraught with all the noxious exhalations of the 
desert. At their approach, the serene sky be- 
comes dark and heavy ; the sun loses its splen- 
dour, and appears of a dim violet hue ; a light 
warm breeze is perceived, which gradually in- 
creases in heat, till it almost equals that of an 
oven. Though no vapour darkens the air, it be- 
comes so grey and thick with the floating clouds 
of impalpable sand, that it is sometimes necessa- 
