Some Notes concerning the Vegetation of Germania Land 373 



March 15, 1908. 



Time 12.5 p. m. 12.50 p. m. 



Air — 22.6 — 23.2 



Black bulb + 5.7 + 4.5 



Difference 28.3 27.7 



March 21, 1908. Sun's altitude 13° 19' 



Time 11a.m. 11.30a.m. 12mid. 12.35p.m. 1.10p.m. 1.30p.m. 



Air —27.2 —25.6 —26.5 —28.5 —26.5 —27.0 



Black bulb + 5.0 + 7.0 + 5.2 + 6.1 4- 6.6 + 3.3 



Difference 32.2 32.6 31.7 34.6 33.1 30.3 



March 26, 1908. 

 Time 1 p.m. Air —11.3 Black bulb -f 15.6 



March 31, 1907. Sun's altitude 17°14' 



Time 11a.m. 11.30 a.m. 12.30 p.m. 



Air —19.2 —19.5 —19.4 



Black bulb + 15.0 + 18.0 -f 14.4 



Blank bulb — 5.0 — 3.8 — 3.7 



March 31, 1908. 



Time 11 a. m. 2 p. m. 



Air —21.5 —18.8 



Black bulb + 7.6 + 12.0 



Difference. 29.1 30.8 



April 2, 1908. 



Time 12 midday 12.50 p. m. 2 p. m. 



Air — 27.2 — 26.4 — 23.2 



Black bulb -h 9.3 +6.6 +11.0 



Difference. 36.5 33.0 34.0 



These observations, which were distributed over 11 days during 

 the years 1907 and 1908, show what is especially characteristic of 

 the radiation, viz. its quick rise in the spring. On March 10, 1907, 

 the black-bulb thermometer, for the first time, reached a positive 

 temperature, and differed from the temperature of the air by 29.6°. 

 Three days afterwards the insolation was + 10.8"; the difference 

 being then 28.5°, the temperature of the air having simultaneously 

 risen 11.1°. The reading on the 15th at 11.30 a.m. gave the same 

 difference. But on the 31st the black-bulb thermometer registered 

 -\- 18.0° with about the same temperature of the air as on the 15th, 

 and the difference then reached 37.5° ; this was the maximum for 

 the year 1907. 



