Page:Popular Science Monthly Volume 43.djvu/151

Rh possible. Other women followed her example, and the fan was invented. The Chinese historians trace the use of the fan in their country back to a contemporary of Rameses II of Egypt; and it is mentioned by a writer of a thousand years before the Christian era. In ancient Grecian life, a eunuch, in one of the tragedies of Euripides, relates how he waved a fan, "according to the Phrygian fashion," before the hair, face, and bosom of the fair Helen. Fans were early adopted by Roman matrons, who had two kinds—the flabella of ostrich plumes, and the labella of thin woven stuff stretched over a frame. A Roman woman never went out without a slave (flabellifera) whose duty it was to fan her. It is not known whether the fan was used in Europe as an article of the feminine toilet between the fall of the Roman Empire and the eleventh century, for it is not mentioned in that relation; but it was certainly used a great deal in the ceremonies of Roman Catholic worship, when the deacons and the acolytes waved it over the altar at mass. This usage Père Bonami assumes to have traced back to the apostles. Fans are represented in manuscripts and on monuments of the twelfth century and inventories of the fourteenth, under different names, but without specification of their use. They seem to have been disused in the church in the thirteenth century, to appear again after the Crusades in the warmer countries—Spain and Italy—as an accessory to woman's dress; but were not seen in France till the sixteenth century, when they were introduced at court by the Italian perfumers who came in the suite of Catherine de Medicis.

American and African Deserts.—The most striking contrast between the North American "deserts" and those of North Africa is described by Prof. Johannes Walther, of Berlin, as consisting in the far greater wealth of vegetation which characterizes the former. In every direction the eye is met by the yellow-blossoming halophytæ, silver-gray artemisiæ, and prickly cacti; between the opuntias are found cushions of moss, and at the foot of the hills juniper trees seven feet high with trunks a foot thick. Such are the features of the landscape of the deserts of Utah, where plant-growth has completely disappeared only in those places in which the saline complexion of the soil kills vegetation. The Van Horn deserts in western Texas, and the Gila deserts in California are equally rich in vegetation; the altitude of these deserts above the sea-level makes no important difference. Either the mean rainfall in the American deserts is greater than in those of Africa, or else the flora of the American deserts is better adapted to a dry atmosphere. Although the deserts of the two continents present fundamental differences as regards vegetation, there is a surprising similarity between them as regards certain important and characteristic desert phenomena, especially with respect to the topography of the country. There is the prevalence of plains, with mountains rising from them like islands, with no intervening heaps of débris passing from the plains to the steep mountain slopes. This phenomenon is the more striking, as there are no rubbish deltas, even at the outlet of valleys a thousand feet deep. Another feature common to both is the large number of isolated "island" mountains and of amphitheatre formations in the valleys; also the intensive effect of insolation, which splits the rocks and flints, and disintegrates the granite into rubbish. The denuding influence of the wind is visible not only in the characteristics of the surface forms just mentioned, which differ in important points from erosion forms, but it can be directly observed in the mighty dust-storms which rush through the desert. In view of such agreement of important and incidental geological phenomena in regions so remote from each other, the phenomenon of desert formation must be considered to be a telluric process which runs its course according to law, just as the glacial phenomena of the polar zone or cumulative disintegration in the tropics.

Wind Effects.—In a paper on The Wind as a Factor in Geology, published in the Engineer's Magazine, Mr. George P. Merrill, after mentioning several familiar examples of the formation of dunes in Europe, passes to the account of similar phenomena in the United States. In May, 1889, a dust-storm occurred in Dakota during which the soil was torn up to a depth of four or five inches and scattered in all directions; while drifts