REPORT OF THE SECRETARY. 39 



off the middle or south Atlantic coast. This new development is not 

 indicated by surface observations, but the Mount Weather flights 

 show north winds at high altitudes in advance of such formation. 

 Again, when an atmospheric depression is approaching from the 

 southwest, and the kite records show winds turning to the right with 

 ascent, the usual warming up in the Atlantic States is retarded about 

 twenty-four hours. Likewise, the turning of the winds to the left 

 with ascent shows the depth of the cold northwest wind, from which 

 inferences may be drawn as to the probable fall in temperature at the 

 surface of the earth within the ensuing twenty-four hours. The 

 thicloiess of the advancing stratum from the west or northwest also 

 furnishes a clue to subsequent temperatures; when shallow, the cold 

 is neither severe nor prolonged; but when the stratum is thick, and 

 abnormally low temperatures are reported aloft, the cold will be of 

 marked intensity and will prevail several days. 



The hurricane season of the year was marked by a number of severe 

 tropical disturbances, but in every instance warnings to shipping and 

 other interests were given sufficiently in advance to enable them to 

 take all necessary precautions. These storms comprise the Galveston 

 hurricane of July 21, 1909, the hurricane that struck the coast near the 

 mouth of the Eio Grande on August 27, 1909, the tropical storm that 

 reached the Louisiana coast on September 21, 1909, and the Key West 

 hurricane of October 11, 1909. That none v/as attended by loss of 

 life is freely attributed by the press and public to the ample advance 

 warnings of the Bureau. A somewhat extended account of the Key 

 West hurricane appeared in my last report, in which it was shown 

 that the special efforts of the Bureau were successfully directed to 

 warning workmen engaged in the extension of the Florida East Coast 

 Railroad, and that about 3,000 emploj^ees were withdrawn from 

 dangerous points as a result of timely advices. 



The cooperation of steamship lines has been requested during the 

 coming year as an aid to the forecaster in predicting the direction 

 of movement and the intensity of hurricanes in southern waters, 

 through the receipt of A\dreless reports from vessels that may encoun- 

 ter conditions indicating the presence of a hurricane in their neigh- 

 borhood. A circular was also issued to storm- warning distributing 

 centers on the Atlantic and Gulf coasts, having for its object a revival 

 of interest in the Bureau's system of furnisliing hurricane warnings 

 to people living in districts where unusually high tides would likely 

 cause loss of life and property. 



Forecasts for extended periods were made from time to time, as 

 justified by general weather conditions, and since the latter part of 

 March, 1910, regular weekly forecasts for the United States, together 

 with a general r^sum6 of the weather for the northern hemisphere, 

 have been issued. Gratifying success has been experienced in the 



