EESULTS OF COMPARATIVE OBSERVATIONS : SWITZERLAND. 255 



and percolation of water, bnt we are not aware that the results of either 

 of these have been published except irregularly. The temperature of 

 trees wasalso observed by placing thermometers in holes bored at breast- 

 high and in the tree tops at the height of 15 meters at the first station, 

 at 9 meters at the second, and at 14 at the third. 



Besides these instrumental stations, observations upon the periodical 

 phenomena of animal and vegetable life, «&;c., were established at over 

 50 stations in the canton, whose elevations were ascertained.* These 

 observations, both instrumental and phoenological, have been continued 

 since 1869 without change, the former being published monthly and the 

 latter annually. Those relating to temperature, moisture, and rain-fall, 

 are of most interest in our present inquiries, and in the absence of pub- 

 lished generalizations," we iiave calculated from the monthly reports of 

 eight years^ (1809 to 1876 inclusive), the following mean results: 



I — Mean temperature of the air at ireast height and in the tree tops. {Centigrade). 



' The returns for November, 1870, are wanting, and the results for that month accordingly em- 

 brace but seven years. 



