158 



SCIENCE. 



[Vol. XIX. No. 476 



four hundred different stocks as against a very few mated in 

 the case of the cow. 



Such deductions as the writer opposes are, in his opinion, 

 misleading-, rest on unstable bases, namely, imagination and 

 tradition, and are better avoided and the time better spent 

 in legitimate genealogical work. To eke out with such 

 matter what is feared will otherwise prove dry and without 

 interest is unscieutific and wrong. With the belief that this 

 review, though hasty, may appeal to the common sense of 

 the conscientious reader the sub-ject is left, the writer believ- 

 ing a simple bi-ief statement of fact preferable to a long and 

 confusing rehash of unnecessary arguments. 



Veritas. 



A COMPARISON OP THE DESERTS OP NORTH 

 AMERICA WITH THOSE OP NORTH APRICA 

 AND NORTHERN INDIA. 



In a paper read before the Geographical Society of Berlin 

 Jan. 2, Professor Johannes Walther made some interesting 

 observations on the deserts of North America, North Africa, 

 and Northern India. It was with the object of being able, 

 from his own observations, to institute a comparison between 

 these deserts that the author took the opportunity afforded 

 by the meeting of tlie Fifth International Congress of Geol- 

 ogists of visiting the North American deserts. 



The most striking contrast between the North American 

 deserts and those of north Africa consists in the far greater 

 wealth of vegetation which characterizes the former. In 

 every direction the eye is met by yellow blossoming halo- 

 phytse, silver-gray artemisise, 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 where the saline composition of the soil kills vegeta- 

 tioQ. The Van Horn deserts in western Texas, the Gila 

 deserts in California, are equality rich in vegetation: the 

 altitude of those deserts above the sea level makes no impor- 

 tant 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 funda- 

 mental differences as regards vegetation, there is a surprising 

 similarity between them as regards cei'tain important and 

 characteristic desert phenomena, especially with regard to 

 the topography of the country. There is the prevalence of 

 plains, with mountains rising from them like islands, with 

 no intervening heaps of debris 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 1,000 feet in depth. Another feature common to 

 both is the large number of isolated '"island" mountains 

 and of amphitheatre formations in the valleys; also the in- 

 tensive effect of insolation, which splits the rocks and flints, 

 and disintegrates the granite into rubbish. The denudating 

 influence of the wind is visible not only in the characteristics 

 of the surface forms just mentioned, which differ in impor- 

 tant points from erosion forms, but it can be directly observed 

 in the mighty dust-storms which riish through the desert. In 

 North America, as in north Africa, four types of denudation 

 products are found — gravel beds, sand dunes, loam regions, 

 and salt deposits. 



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 cumula- 

 tive disintegration in the tropics. Water, which is such a 

 predominating influence in temperate regions, destroying 

 the rocks, dissolving them chemically, while the frost pounds 

 them up mechanically, has in the deserts about sixty days 

 in the course of the year to do its work of destruction among- 

 the rocks and to carry away debris. During the remaining 

 300 days of the year denudation in the desert is at a stand- 

 still, but not entirely. Small and large stones are split by 

 the heat, and huge granite blocks are severed in two by im- 

 mense Assures; and thus the rocks are destroyed by dry heat 

 at a time when denudation by means of water is reduced to 

 a minimum. In this way the process of destruction goes on. 

 in one form or other uninterruptedly throughout the whole 

 year. The disintegrated material is then carried away by 

 the desert rains or by the storms, which whirl great masses 

 of loose matter high into the air and transport it further. It 

 is clear, therefore, that dry denudation possesses an intensive 

 power which, although not equal to the denuding effect of 

 water, may be compared with it. 



NOTES AND NEWS. 



In the death of Thomas Hockley, which occurred on the 12tb 

 of March, in Philadelphia, the scientific institutions in that city 

 have suffered a serious loss. Mr. Hockley was a member of nearly 

 all the local learned societies, and as an ofiScer of many of them 

 did much to promote scientific woi-k. As treasurer of the Uni- 

 versity Arehseological Association, the Department of Archaeology 

 of the University of Pennsylvania, the Numismatic and Anti- 

 quarian Society, as well as of the Zoological Society and the Fair- 

 mount Park Art Association, he gave his services without pecuniary 

 profit or even the prominence which he deserved, and he will be 

 remembered as one who did uiuch to advance public interests 

 through self-sacrificing devotion to the general good. 



— At the Berlin Geographical Society, on Jan. 3, Herr L. 

 Cremer read a report upon the journey undertaken by him in the- 

 summer of 1891 to Spitzbergen, with the object of exploring the 

 coal beds there. The author in the course of his six weeks'" 



•journey travelled along the west coast as far as Magdalena Bay, 

 and found, besides the coal beds in Ice Fjord and Bell Sound,, 

 which were discovered by Swedish explorers, various other coal- 

 veins which appear to be well worth working. 



— In the second lecture of the Lecture Association of the Uni- 

 versity of Pennsylvania's course on "Early Religious Ideas," on 

 Feb. 28, Mrs. Cornelius Stevenson spoke as follows: "The primi- 

 tive animism of the men of the age of stone always remained at 

 the foundation of the religion of Egypt, and continued to develop 

 its superstitious practices, whilst the national faith had assumed 

 an ever-growing metaphysical character. At the opening of his- 

 tory the Egyptians had already recognized the unity of the life- 

 giving principle, but whatever may have been the ideas of their 

 advanced thinkers with regard to the nature of the unity, there 

 is no doul)t that, to each local worshipper, the god he prayed to 

 was strictly the god worshipped in his locality — and this did not 

 exclude the recognition of the other gods. The whole structure 

 of the Egyptian religion rested upon a belief in the divine nature 

 of life, and, in its immortality through transformation, man could 

 attain his immortality, not (in early times) through his merits, 

 but through physical means. Hence the precautious taken to pre- 

 serve the remains, and the statues made in his image, on which 

 the spirit might lean in case his body should be destroyed. Meta- 

 physical speculation on the nature of the universal soul grew out 

 of solar worship, and, influenced by Aryan contact, at last super- 

 seded it. But even then the primitive animism, preserved in the 

 cultus of the sacred animals regarded as incarnations of the 

 divinity, although it assumed in the sanctuary a symbolic char- 



