FALLEN RAIN. 67 



times wrongly compared, because the ditference in 

 rainfall may be caused by the difference in altitude. 

 Finally, the best observations that have been made 

 point to different conclusions. For example, measure- 

 ments taken in Prussia go to show that there is an 

 increase of rain over the forest, and that it is greater 

 the higher the station. Thus, near the level of the sea 

 it was only 1.25 per cent greater than over the open 

 country, while at altitudes between 2,000 and 3,000 feet 

 it reached 43 per cent. Observations made at Nancy, 

 in France, w^hich lies about TOO feet above the sea, show 

 an average yearh^ increase of 16 per cent. The Bava- 

 rian observations, on the contrar}^, do not indicate 

 more rain over the forest. The best evidence at hand 

 fails to show a decrease in rainfall over the United 

 States in the last hundred years, in spite of the im- 

 mense areas of forest that have been burned and cut. 

 But it should not be forgotten that most of those areas 

 have grown up again, first with brush, and afterwards 

 with trees, so that the proportion of land covered with 

 leaves is still very large in all that part of the country 

 which was once under forest. In India, again, a large 

 amount of statistics has been collected which leads to 

 the conclusion that forests do influence rainfall. The 

 truth probably is that more rain falls over the forest 

 than over open country similarh^ placed, but how much 

 more it is impossible to sa}". The excess falls chiefly 

 in the form of summer showers. One of the best 

 authorities has estimated the difference at 10 per cent. 



FALLEN KAIN. 



Whatever doubt there may be about the action of 

 the forest in producing rain, there is none about its 



