THE "HARM ATT AN." 89 



to simplify and methodise these researches, a paper is subjoined particularising the various 

 departments in reference to which information is more especially wanted ; so that each officer 

 may select one or more of those departments most congenial to his tastes and inclinations. 



"All captains and commanders are required to render every facility consistent with the proper 

 duties of their respective vessels to those officers who may manifest a zealous co-operation in the 

 pursuits herein specified ; and it is to be plainly understood that I do not officially require the 

 officers to perform any involuntary duty. I shall exact that only which may come within the 

 legitimate sphere of my authority, leaving to the officers themselves to engage, as far as they 

 may see fit only, in those investigations which, in an official point of view, may be considered 

 as on their parts gratuitous. 



"It will always give me the greatest pleasure to bring to notice the labors of each and every 

 individual who may contribute to the general work." * 



During the 21st, 22d, and 23d of December, the wind continued from the northward and 

 eastward ; about noon of the 23d it inclined to the southward of east, hauling around at night, 

 however, more to the north ; and on the 24th, when the ship was abreast of Brava and Fogo, 

 it stood at E.N.E. 



The haze, however, was such that nothing more than a glimpse could be obtained of Fogo ; 

 and the winds are thus particularly referred to above because of their possible connexion, at 

 this time, with the haze. They are physical facts, and therefore ought to be recorded. This 

 haze is common to these latitudes, and is by many supposed to be caused by what is called the 

 "Harmattan." This is the name given to a wind which, passing over Africa, takes up in its 

 sweep, as is supposed, an impalpable dust, and carries it far away to the westward. The 

 Commodore himself had remarked the haze or dust, on former cruises, more than five hundred 

 miles west of the Cape de Verd islands. When commanding a squadron, in 1844, on the 

 western coast of Africa, he had carefully noted several facts connected with this wind, certainly 

 the most remarkable on that coast. A thousand incredible stories are told of its singular effects. 

 It is said, for instance, that its dry and subtle properties will check or cure various diseases, 

 heal up the most inveterate ulcers, destroy cabinet work, break window glass, and stop the 

 motion of timepieces. But apart from these strange stories, it must still be said that the efiects 

 of this wind are extraordinary. In some respects it resembles the Sirocco, and also the 

 Levanter of the Grecian archijielago. 



It commences about the middle of December, and continues until the latter end of March. 

 Like the Sirocco, it has been supposed to take its rise in the deserts of Africa ; but, unlike the 

 Sirocco, instead of producing a burning and oppressive temperature, it is a chilling wind. Its 

 direction is always from the land, and it sometimes increases to a strong breeze ; it does not, 

 however, blow steadily during its season, but frequently intermits, when land or sea breezes 

 take its place. 



At the Cape de Verds and the Gambia, the "■ Harmattan ' ' appears to form a junction with 

 the northeast trades prevailing there at a certain season, and to blow with little interruption 

 from January until April. 



*The subjects suggested by the Commodore, in his order, embraced hydrography, meteorology, naval architecture in its 

 adaptation to war and commerce, military affairs, geology, geography, terrestrial magnetism, philology and ethnology, artistic 

 matters, costumes, &c., religions, diseases and sanitary laws, agriculture, statistics of supplies, botany, entomology, 

 ornithology, zoology, conchology, ichthiology, and the magnetic telegraph ; and we trust the appendices to this narrative will 

 show that the commander did not misjudge either as to the attainments or zeal of his officers. 



12 J 



