234 COMPARATIVE METEOROLOGICAL OBSERVATIONS. 



G. Winds. — Where the situation permits, the wind-vane should be fixed on a dwell- 

 ing, and should be fastened to a spindle which reaches the ceiling of a room on the 

 first floor, with an index corresponding with the indications of the vane on a dial 

 marked with the eight principal points. In classifying the different degrees of force, 

 signifies calm ; 1, a slight wind, gently moving the leaves ; 2, a moderate wind, which 

 moves the branches of the trees in the open field and creates a slight noise ; 3, a strong 

 wind, moving the larger limbs of trees, walking against it being difficult, and light 

 objects being carried by it into the air ; and 4, a storm, keeping the trees in constant 

 motion, and occasionally breaking branches and carrying leaves and dust to a great 

 height, accompanied by a loud whistling noise and incessant guats of wind. Walking 

 against this wind is difficult and almost impossible. 



7. Cloudiness. — The extent of cloudiness is divided into four degrees: denotes a 

 clear sky, and 4 denotes entire cloudiness, and is also used for a thick fog or a rain that 

 covers the whole horizon. The numbers 1,2,3 denote intermediate degrees. 



8. Movement of clouds. — The direction of movement in clouds should be noted 

 where possible, and, if at different heights, their several directions. No entries are to 

 be made where the motion cannot be ascertained. 



9. Precipitation. — In recording watery deposit, R is used for rain ; S, for snow ; R 

 S, for rain and snow ; H, for hail ; SI, for sleet ; D, for dew ; F, for frost ; and Fg, for 

 fog. The latter may be rising, falling, heavy or thick, moderaie or slight, and should be 

 marked by these words. The time of occurrence and the duration of these several 

 forms of precipitation are to be indicated by adding two figures denoting their begin- 

 ning and ending, as R, 2-6 p. m. 



Hours for observation. — Daily observations should be made at 9 a. m. and 5 p. m. from 

 March to November, inclusive, and at 9 a.m. and 4 p.m. in December, January, and 

 February. In expectation of prompt attention to their duties on the part of observers, 

 the number of daily observations has been fixed at two only. At 9 a. m. the minimum 

 temperature of the night, and at 5 p. m. the maximum of the day should bo read on 

 the thermometrograph and entered, always readjusting the instrument. One daily 

 observation of the rain, at 5 p. m., is sufficient, unless unusually heavy rains should 

 make more than one measurement necessary. 



The instruments in the open fields should be read first, and those in the woods im- 

 mediately after. First note the temperature of the air on the dry thermometer of the 

 psychrometer ; next wet the other bulb ; then read the maximum and minimum ther- 

 mometer ; then the atmometer, rain-gauge, and earth thermometers ; and lastly, read 

 the wet bulb thermometer. After this, note the winds, cloudiness, and any remarks 

 that may be necessary. On the last day of each month the water is drawn off from 

 the sunken vessel and measured. Days on which, at any of the designated hours of 

 observation, the temperature is below the freezing point, or frost has occurred during 

 the night, are to be noted as " frost days," or if snow has fallen, " snow days." If, from 

 any cause, the observer is prevented from making the observations himself, he must 

 employ a competent and reliable person to supply his place. When this is not 

 practicable, the columns under their respective heads must be left blank. If, how- 

 ever, within an hour or two afterward, he should be enabled to make the observation 

 himself, he must do so, noting the time under the head of " remarks." Under no circum- 

 stances should the observer enter anything in the tables obtained from his own calcu- 

 lations on guess-work. It is recommended to observers that they never rely upon mem- 

 ory, but that they make the entries in pencil in a memorandum-book at each reading, 

 and immediately after reading, the same to be copied into the blanks as soon as ho 

 reaches home. 



Transmission of the tables. — On the first day of each month the tables are to be trans- 

 mitted to the director of the Central Forest Academy. Each observer will receive two 

 blanks for each month, one of which he may retain for his own use. In all cases the 

 original is to be sent — never the copy. 



Under this system of observation seven stations were established, 

 viz : At Diischlberg (2,776 Paris feet above sea-level) ; at Sceshaupt 

 (1,830 feet); at Bohrbrunn (1,407 feet); at Johanneslcrenz (1,407 feet); 

 at Ebracli (1,172 feet); at Altenfurth (1,400 feet); ^nd Aschaffenburg 

 (400 feet). For a part of the time observations were included from Pro- 

 menliof. Tbe temperatures given are those of Keaumur's scale, in which 

 freezing water is 0^, and boiling water 80°. 



At the end of four years a synopsis of results was published by Dr. Ernst 

 Ebermayer,^ from which the following summary is derived. They are ac- 



^ Die physikalischen Eimvirlcungen des Waldes aiif Luft und Boden, nnd seine Idimatolo- 

 gische and hygicncsche Bedeutung. Berlin (1873), pp. xii, 266, and 253, with an atlas. 

 Dr. Ebermayer has also iiublished another volume of forest results of observations 



