SUNSHINE AND CLOUDINESS IN NEBRASKA. 47 



age of 8.0 hours; June averages 7.5 hours; and September 7.4 hours. 

 It will thus be seen that the percentage of sunshine is relatively great- 

 est at that season of the year when crops are ripening and being har- 

 vested, in other words, when sunshine is most welcome to the ao'ri- 

 cullurist. 



As to the intensity of sunshine in Nebraska we know as yet but 

 little by direct measurement of it. A few months' observations have 

 been made at the experiment station at Lincoln with a self- registering 

 actinometer, but the data are as yet too few to give much information. 

 By inference, however, we know that the intensity of the sun's rays 

 in Nebraska is greater than in most parts of the country. Our abso- 

 lute humidity, or the actual amount of moisture present in the atmos- 

 phere, is decidedly less on the average than in the states lying nearer 

 the seaboard or to the great lakes, and this low degree of humidity is, 

 to some extent, a measure of the capacity of the atmosphere to trans- 

 mit the sun's rays. Further, the number of days in summer with a 

 high mean temperature is large for this latitude and argues large pen- 

 etrating power for the sun's rays. 



It will thus be seen that in the years when we have our normal 

 amount of rainfall the conditions could scarcely be more favorable 

 than they are in Nebraska; with about two-thirds of our rainfall oc- 

 curring in the' five months of the growing season and reaching its 

 maximum in the earlier part of the season when growth is most rapid, 

 and with sunshine at a maximum when crops are maturing and being 

 gathered we have conditions well nigh ideal. 



But what shall we say of the years of drought when the intensity 

 and duration of sunshine proves an adversary instead of a friend? It 

 is important then that we should clearly understand the forces with 

 which we have to contend, and should so cultivate our farms and 

 orchards as to reduce the evil to its lowest terms. At the summer 

 meeting of the Society I presented facts showing how excessive is our 

 evaporation and how important therefore that, by means of surface 

 cultivation and mulching, we should husband our resources in the mat- 

 ter of soil moisture. The facts presented to-day will show one reason 

 why evaporation is so large in the summer months and will serve to 

 emphasize this matter of the importance of learning how to handle the 

 soil to the best advantage, which is evidently one of the problems which 

 is to demand our careful attention here in Nebraska. 



