REPORT OF THE CHIEF OF THE WEATHER BUREAU. 



United States Department of Agriculture, 



Central Office of the Weather Bureau, 



Washington, D. C, October 10, 1910. 

 Sir: I have the honor to submit a report of the operations of the 

 Weather Bureau during the fiscal year ended June 30, 1910. 



Willis L. Moore, 

 Chief of Weather Bureau. 

 Hon. James Wilson, 



Secretary of AgHculture. 



MOUNT WEATHER RESEARCH OBSERVATORY. 



Upon the completion of the new main observatory at Mount 

 Weather, the necessary instrumental equipment for taking a full set 

 of meteorological observations was immediately installed, and the 

 first observation in the new building w^as made on February 18, 1910. 



Two observations of the surface meteorological conditions are 

 made daily and telegraphed to Washington, D. C. These observa- 

 tions form a part of the general groundwork upon which the daily 

 forecasts of the weather are made. 



aerial research. 



In addition to the observations of the surface conditions, there is 

 also telegraphed to Washington each day a brief statement of the 

 observations made in the free air at different heights above Mount 

 Weather. 



In the beginning of aerial research by the Weather Bureau, in 

 1897, it was conceived that a synoptic chart of upper-air conditions, 

 made daily, if possible, would be a decided gain to meteorology. 

 Therefore a network of 17 stations was equipped with kites as the 

 sole means of sending recording instruments into the air. It soon 

 developed that kite flights could be made only on daj^s when there 

 was sufficient wind, and that these formed a smaller percentage of 

 the whole than was expected. For this and other reasons the plan 

 of constructing a chart of upper-air conditions was abandoned. 



In planning the upper-air work at Mount Weather, advantage was 

 taken of this earlier experience, and nn equipment was installed that 

 promised to insure flights in almost any kind of weather. To a cer- 

 tain extent the equijiinent now on hand has fulfilled its promise. 

 At times, however, the winds blow over the mountains at almost 



73477°— AGR 1910 11 161 



