126 



FORESTRY IN GERMANY. 



The following table gives the difference in temperature according to observa- 

 tions made at Berne, Switzerland : 



S/iozuing difference in tejuperattcre lo feet above ground^ according to observations at 

 Berne, Switzerland, for the years iS6g to j88o. 



Spring. 



Summer. 



Winter. 



1870. 

 1871. 

 1872. 

 1873. 

 1874. 

 1S75. 

 1876. 

 1877. 

 1878. 

 1879. 



-1.39 

 —1.24 

 -1.63 

 -r.28 

 -0.98 

 -0.89 

 —1.04 

 -0.52 

 -0.36 

 -I. OS 

 -2.12 

 -0.06 



The foregoing table indicates that the temperature throughout the year, 

 on an average, is lower in the forest than in the open land ; but this cooling 

 influence is most noticeable in mid-summer, is very small in winter, and is 

 about half way between the two in spring and autumn. 



The difference between the temperature of the ground in the forest and 

 on open land for an average of twelve years (1869 to 1880), at three stations 

 in Switzerland, was as follows: 



It remains, however, to be demonstrated how great the influence of this 

 difference of temperature in the forest and open land is on the general 

 climate of the country, and whether the temperature outside of the forest is 

 conditioned upon it. 



No data are given as to what proportion of forest is the most favorable for 

 vegetation and health. 



The relative humidity of the air in the forest and on the open land is 

 given by Professor Ebermayer, as follows : 



