Dust-winds at Hankow

Abstract

DURING the spring of 1878 my attention was directed to the dust-winds which are not of unfrequent occurrence along the valley of the Yang-tse in the warm and dry seasons of the year. These dust-winds, as I observed them at Hankow, had sometimes the appearance of a dense mist; whilst at other times the air seemed to be penetrated by a fine haze; and in all cases a fine and almost impalpable dust was deposited which was with difficulty excluded from the interior of houses. Their duration varied from a few hours to two days; and from the fact that one of the dust-winds was simultaneously experienced at Hankow, Kiukiang, and Chinkiang—a portion of the river's course nearly equal to 450 miles— I may conclude that they were not local phenomena, but possessed a considerable horizontal extension. The dust, which in all respects resembles the loam forming the banks and alluvial plains of the Yang-tse, is composed of mineral particles and vegetable débris—the former varying from 1/500 to 1/1000 of an inch in size, and being generally siliceous or calcareous in composition.