North of lat. 19°, the prevailing winds are from the north or north-west, while in the south the predominating winds are from the south and south-east, between the two lying a belt of variable winds. From June to August north-west winds prevail over the whole Red Sea. This is known as the “Kamsin,” or fifty days’ wind, the word being derived from the Arabic root of that numeral, which, originally, intensely hot and dry, rapidly takes up moisture from the water, and is hence particularly insupportable on the Arabian side of the sea; though the fine sand with which it is loaded makes it equally objectionable from another point of view on the African side. Its velocity is often considerable, and under such circumstances may be even dangerous to the lives of those who are so unfortunate as to be exposed to its fury in the open desert. The extremely fine dust penetrates everywhere in spite of closed doors and windows, reaching even ships far out at sea. Fortunately, on the coast it is generally a good deal modified by sea-breezes springing up in the afternoon, but there is also a tendency to fall dead calm at night, under which circumstances the dark hours are even more intolerable than those of the day. The following table of the principal climatic data of Massawa in the Italian colony of Erythrea, compiled from data contained in a pamphlet by Dr. Giovani Petella, of the Royal Italian Navy, gives a good idea of the character of the climate of the Red Sea littoral. MASSAWA. LAT. 16° N.; NEAR SEA-LEVEL.