NOVEMBEE 6, 1908] 



SCIENCE 



653 



purpose. The placing of wire netting around 

 the louvered shelter where the meteorograph 

 is installed might give this instrument pro- 

 tection from electric shock, hut the projection 

 of the wind vane and anemometer masts from 

 the shelter may attract sufficient electricity to 

 fuse the netting and reach the instrument by 

 way of the mechanical connections. There 

 has been actual danger on Mount Rose, so far 

 as known, only this single time during the past 

 three years. J. E. Church, Jr. 



Univeesity of Nevada, 

 Reno, Nevada 



the blowing of soils 



When a boy on my father's farm in Iowa 

 I experienced a three days' dust storm, when 

 the air was so full of dust that one could 

 hardly see, and the sun was almost obscured. 

 After the storm I noticed that drifts of loose 

 earth had accumulated in all the protected 

 hollows, in the lee of corn shocks and fences, 

 and on the grass lands adjacent to the cul- 

 tivated fields. We had no other storm so 

 severe as this one, but I noticed that the drift- 

 ing soil particles in the air were gradually 

 filling up a small pond that adjoined a plowed 

 field. This little pond was so situated that 

 no wash from the plowed area could enter it, 

 and its filling up was undoubtedly due to the 

 deposition of wind-blow particles. Some years 

 ago I again visited the place and found that 

 this pond was dry and filled up practically 

 level with the surrounding land. 



In the spring of 1889 I had occasion to 

 observe the erosion by the wind of a recently 

 plowed field on my father's farm, near Yates 

 Center, Kan. The field sloped gently toward 

 the southwest, and for several days the wind 

 blew violently from that direction, carrying 

 away the soil in some of the most exposed 

 places to the full depth to which it had been 

 loosened by plowing. Most of the soil was, of 

 course, dropped in the lee of the first obstruc- 

 tion; but the finer particles were probably 

 carried for many miles. Other fields in the 

 vicinity suffered the same fate, and after the 

 siorm was over our neighbor adjoining us on 

 the north had the bulk of our soil. Most of it 



piled in big drifts just back of an osage 



Later, near Albuquerque, N. M., and at 

 Cibicu, Ariz., I was impressed by the strong 

 indications of eolian origin offered by the 

 adobe clay of this region. This material can 

 hardly have been formed by glacial action as 

 no traces of such can be found, and fluvial 

 action is in most cases excluded by the topog- 

 raphy. The deposit is found superimposed 

 on many geologic formations and at a wide 

 range of altitudes. It may be partly rain 

 wash •from the hills, but were it entirely so it 

 would show a non-uniformity of mechanical 

 composition — becoming finer in grain with 

 distance from the hills. This does not 

 occur — the deposit being very uniform. It is 

 also remarkably level, showing no traces of 

 the descending slopes characteristic of alluvial 

 fans. Becoming convinced that this deposit 

 was largely of eolian origin, I began to look 

 about for evidences that deposits are made and 

 materials moved by the wind. The following 

 observations resulted: 



1. On the Jemez coal lands near Albu- 

 querque, N. M., it was noticed that, on windy 

 days, a sheet of dust was continually blown 

 completely over the region from Mesa Blanca 

 and adjacent ridges. 



2. At Cibicu, Ariz., fine dust settled on any- 

 thing spread on the ground after a reddish 

 southwestern sky at sunset, indicative of dust 

 storms in the Gila-Salt River desert many 

 miles away. This happened even when there 

 was apparently no wind at Cibicu during the 

 previous night and the day. 



3. During a year of very slight rainfall at 

 Fort Apache, Ariz., the adobe flats received 

 even more increment than in years when the 

 rainfall was normal. In this region the soil 

 particles are continually being blown to the 

 eastward from the region to the south of the 

 long tongue-like ridge of the Mogollon range 

 which extends to within a few miles of Fort 

 Apache, and the dirt is being collected in the 

 grass-covered area to the leeward of this ridge, 

 but so slowly that the growth of vegetation 

 keeps pace with the deposition. 



4. The accumulation of wind-blown earth is 



