HARMATTAN, the name of a remarkable periodical wind which blows from the interior parts of Africa towards the Atlantic Ocean. Of this wind we have an account {Philosophical Transactions, vol. lxxi.) furnished by Mr Norris, a gentleman who had frequent opportunities of observing its singular properties and effects.

On that part of the coast of Africa which lies between Cape Verde and Cape Lopez, an easterly wind prevails during the months of December, January, and February, which by the Fantees, a nation on the Gold Coast, is called the Harmattan. Cape Verde is in 15° north latitude, and Cape Lopez in 1° south latitude; and the coast between these two capes runs in an oblique direction nearly from west-south-west to east-south-east, forming a range of upwards of 2100 miles. At the Isles de Los, which are a little to the northward of Sierra Leone, and to the southward of Cape Verde, it blows from the eastsouth-east, on the Gold Coast from the north-east, and at Cape Lopez, and the river Gabon, from the north-northeast. This wind is by the French and Portuguese, who frequent the Gold Coast, called simply the north-east wind, the quarter from which it blows. The English, who sometimes borrow words and phrases from the Fantee language, which is less guttural and more harmonious than that of their neighbours, adopt the Fan tee word harmattan.

The harmattan comes on to blow at any hour of the day, at any time of the tide, or at any period of the moon, and continues sometimes only a day or two, sometimes five or six days; but it has been known to last fifteen or sixteen days. There are generally three or four returns of it every season. It blows with a moderate force, not quite so strong as the sea-breeze, which every day sets in during the fair season from the west, west-south-west, and south-west, but somewhat stronger than the land wind at night from the north and north-north-west.

A fog or haze is one of the peculiarities which always accompanies the harmattan. The gloom occasioned by this fog is so great, as sometimes to obscure objects near at hand. The English fort at Whyddah stands about midway between the French and Portuguese forts, and not quite a quarter of a mile from either, yet often neither of the other forts can be discovered from the intermediate one. The sun, concealed during the greater part of the day, appears only a few hours about noon, and is then of a mild red, exciting no painful sensation in the eye.

Extreme dryness is another property of this wind. No dew falls during the continuance of the harmattan; noris there the least appearance of moisture in the atmosphere. Vegetables of every kind are much injured; all tender plants, and most of the productions of the garden, are destroyed; the grass withers, and becomes dry like hay; the vigorous evergreens likewise feel its pernicious influence; the branches of the lemon, orange, and lime trees droop; the leaves become flaccid, wither, and, if the harmattan continues to blow for ten or twelve days, are so parched as to be easily rubbed to dust between the fingers; and the fruit of these trees, deprived of its nourishment, and stinted in its growth, only appears to ripen, becoming, in fact, yellow and dry, without acquiring hall the usual size. The natives take the opportunity of the extreme dryness of the grass and young trees to set fire to them, especially near the roads, not only to keep those roads open to travellers, but to destroy the shelter which long grass, and thickets of young trees, would afford to skulking parties of their enemies. A fire thus lighted spreads with such rapidity as to endanger those who travel. In this situation a common method of escape is, on discovering a fire to windward, to set the grass on fire to leeward, and then follow your own fire. There are other extraordinary effects produced by the extreme dryness of the harmattan.

The parching effects of this wind are likewise evident on the external parts of the body. The eyes, nostrils, lips, and palate, are rendered dry and uneasy, and drink is often required, not so much to quench thirst, as to remove a painful aridity in the fauces. The lips and nose become sore, and even chapped; and though the air be cool, yet there is a troublesome sensation of prickling heat on the skin. If the harmattan continues four or five days, the scarf skin peels off, first from the hands and face, and afterwards from the other parts of the body, if it continue a day or two longer. Mr Norris observed, that when by exercise sweat was excited on those parts which were covered by his clothes from the weather, it was peculiarly acrid, and tasted, on applying his tongue to his arm, something like spirits of hartshorn diluted with water.

Salubrity forms a third peculiarity of the harmattan. Though this wind is so very prejudicial to vegetable life, and occasions such disagreeable parching effects on the human species, yet it is highly conducive to health. Those labouring under fluxes and intermitting fevers generally recover during an harmattan. Those weakened [7:11:149]by fevers, and sinking under evacuations for the cure of them, particularly bleeding, which is often injudiciously repeated, have their lives saved, and vigour restored, in spite of the doctor. It stops the progress of epidemics; the smallpox and intermittent fevers not only disappear, but those labouring under these diseases, when an harmattan comes on, are almost certain of a speedy recovery.

This account, however, differs from that given by Dr Lind, who calls the harmattan a malignant and fatal wind. (See his Diseases of Hot Climates.)