300 THE SEASONS CLIMATE AND HEALTH 



Region are to be accounted for, first, because this region lies in 

 the path of the numerous northwest storms, and second, be- 

 cause the water surfaces offer less resistance to the moving air. 



The high winds of the western plains may also be accounted 

 for, first, by noting the even slope of the land from the Rockies 

 eastward and the treeless character of this region, and second, 

 the marked difference in the temperature of the mountain 

 region on the west and of the Mississippi valley on the east 

 during the summer months (see Fig. 218). 



As an aid in selecting a location having a suitable climate 

 little general information regarding winds can be given. Both 

 their velocity and direction are largely determined by local 

 conditions. 



D. SUNSHINE 



320. Sunshine. Physicians, as well as all thinking and 

 observing people, have great faith in the curative and health- 

 giving power of sunshine. The sun bath is frequently pre- 

 scribed in the treatment of many diseases. Direct sunlight 

 is known to be one of the best of germicides; most disease germs 

 die quickly when exposed to the direct rays of the sun. Even 

 diffused sunlight is known to have great germicidal effects. 

 So widespread and strong has become the faith in the beneficial 

 effects of sunlight, that modern architecture has felt its in- 

 fluence. Modern dwellings as well as hospitals and sanatoriums 

 are being constructed more and more with the view of admit- 

 ting the largest amount of direct sunlight possible. Figs. 

 225 and 226 show the relative amounts of sunshine for the 

 United States for the summer months and winter months. 



Exercise 72. Study of the Sunshine Maps, Figs. 227 and 228 



What portion of the United States has the highest percentage of 

 sunshine? What portion the lowest? 



Is the percentage of sunshine greater in the summer or in the winter? 



Compare the sunshine map for the summer months with the rela- 

 tive humidity map for the same months. Is there any similarity? 



