Egypt is infested with the destructive blasts common to all warm countries which have deserts in their neighbourhood. These have been distinguished by various names, such as Poisonous winds, Hot winds of the desert, Samiel, the wind of Damascus, Camseen, and Simoom. In Egypt they are denominated "Winds of fifty days," because they most commonly prevail during the fifty days preceding and following the equinox, though, should they blow constantly during one half of that time, an universal destruction would be the consequence. Of these, travellers have given various descriptions. M. Volney says, that the violence of their heat may be compared to that of a large oven at the moment of drawing out the bread. They always blow from the south, and are undoubtedly owing to the motion of the atmosphere over such vast tracts of hot sand, which cannot be supplied with a sufficient quantity of moisture. When they begin to blow, the sky loses its usual serenity, and assumes a dark, heavy, and alarming aspect, the sun laying aside his usual splendour, and becoming of a violet colour. This terrific appearance seems not to be occasioned by any real haze or cloud in the atmosphere at that time, but solely by the vast quantity of fine sand carried along by those winds, and which is so excessively subtile that it penetrates every where. The motion of this wind is always rapid, but its heat is not intolerable till it has continued for some time. Its pernicious qualities are evidently occasioned by its excessive aridity; for it dries and shrivels up the skin, and, by affecting the lungs in a similar manner, soon produces suffocation and death. The danger is greatest to those of a plethoric habit, or who have been exhausted by fatigue; and putrefaction very soon takes place in the bodies of such as are destroyed by it. Its extreme dryness is such, that water sprinkled on the floor evaporates in a few minutes; all the plants are withered and stripped of their leaves, and a fever is instantly produced in the human species by the suppression of perspiration. It usually lasts three days, but is altogether insupportable if it continue beyond that time.

Damascus.

The danger is greatest when the wind blows in squalls, and to travellers who happen to be exposed to its fury without any shelter. The best method, in this case, is to stop the nose and mouth with a handkerchief: camels, by a natural instinct, bury their noses in the sand, and keep them there till the squall is over. The inhabitants, who have an opportunity of retiring to their houses, instantly shut themselves up in them, or go into pits made in the earth, till the destructive blast is over.

The description of a blast of this kind, which overtook Mr. Bruce, in the desert of Nubia, is still more terrible. - The sun was now obscured by them,* and the transmission of his rays gave them a dreadful appearance, resembling pillars of fire. This was pronounced by the guide to be a sign of the approaching simoom, or hot wind; and he directed, that when it came, the people should fall upon their faces, and keep their

The moving columns of sand.

mouths on the sand, to avoid drawing in this pernicious blast with their breath. On his calling out that the simoon was coming, Mr. Bruce turned for a moment to the quarter from whence it came, which was the south-east. It appeared like a haze or fog of a purple colour, but less bright than the purple part of the rainbow; seemingly about twenty yards in breadth, and about twelve feet high from the ground. It moved with such rapidity, that before he could turn about and fall down, he felt the vehement heat of its current upon his face; and even after it passed over, which was very quickly, the air which followed was of such a heat as to threaten suffocation. Mr. Bruce had unfortunately inspired some part of the pernicious blast; by which means he almost entirely lost his voice, and became subject to an asthmatic complaint, from which he did not get free for two years.

The same phenomenon occurred twice over on their journey through this desert. The second time it came from the south a little to the east, but it seemed to have a shade of blue along with the purple, and its edges were less perfectly defined, resembling rather a thin smoke, and having about a yard in the middle tinged with blue and purple.

The third time, it was preceded by an appearance of sandy pillars, more magnificent than any they had yet observed; the sun shining through them in such a manner as to give those which were nearest a resemblance of being spangled with stars of gold. The simoom which followed had the same blue and purple appearance as before, and was followed by a most suffocating wind for two hours, which reduced our travellers to the lowest degree of weakness and despondency.

It was remarkable, that this wind always came from the south-east, while the sandy pillars, which prognosticated its approach, seemed to keep to the westward, and to occupy the vast circular space inclosed by the Nile to the west of their route, going round by Chaigie towards Dongola. The heaps of sand left by them when they fell, or raised by the whirl-winds which carried them up, were twelve or thirteen feet high, exactly conical, tapering to a fine point, and their bases well proportioned.