30 FOREST INFLUENCES. 



been printed a separate publication on this subject, but I have not seen 

 it; its data are said by Dr. Lorenz-Liburnau to differ somewhat liom 

 those in the Com])tes rendus. 



GERMANY. 



In 1808, witli the aid of the Bavarian Government, Dr. Ebermayer 

 began his well-known series of observatious. The results for the first 

 year were made the subject of an independent publication. They relate 

 exclusively to the problem of the interior forest climate, and the con- 

 clusions reached by Dr. Ebermayer have been generally confirmed by 

 later observations. Dr. Hough has devoted twenty pages of his report 

 for 1877 (pp. 230-251) to an account of this service and an abstract 

 of its results, so that they do not need to be detailed here. Dr. Eber- 

 mayer, then in the forestry school at Aschaffenburg, is now professor 

 at Muuich, and his publications on forest meteorological topics still con- 

 tinue. In the beginning of 18G9 three pairs of parallel stations were 

 established in Switzerland. They are also described by Dr. Hough in 

 his report (p. 255) cited above. 



In 1875 the German meteorological forestry service was established. 

 The stations are here in pairs, one in the forest, the other outside, and 

 the observatious are made in succession at the two stations of each 

 pair. The rule was adopted to have each of the stations at least 200 

 yards (182.8 meters) from the margin of the forest, but this was not 

 found to be always practicable, and the distance in one place sinks to 

 less than ninety yards (82.29 meters). The stations were selected to rep- 

 resent every variety of position possible as to distance from the coast, 

 topography, and kind of trees, and each station of the pair was put 

 under very similar conditions of soil and elevation. Seventeen such 

 stations have been established; ten in Prussia, three on the Imi^erial 

 lands, and one each in Wiirtembcrg, in Brunswick, in Thuriugia, and 

 in Hanover. The observ-ations at Wiirtemberg station continued only 

 from the beginning of 1880 to the end of 1885. The other stations are 

 still active; they are conducted on a uniform jdan and arc under the 

 direction of Dr. Miittrich, of the academy of Eberswalde. The instru- 

 ments are made by Fuess; they are carefully compared when put up 

 and are regularly inspected once in five years. Instruments are kept 

 in reserve at each station so that the defective ones can be at once re- 

 X)laced without breakiug the continuity of the observatious. 



The Hanover station is Lintzel, and this is exceptional in that it is 

 among the young plantations of trees now formed on the great Luue- 

 berger heath. Field and forest stations both exist, but tree-top obser- 

 vations are not made. The in^ncipal features of the stations are shown 

 in the accompanying table, in which they are arranged in order from 

 northeast to southwest. By the elevation is meant that indicated by 

 the barometer, which is so nearly the same for each station of the pair 

 that it may be taken from either. The readings are exact, except for 



