REPORT OF THE SECRETARY. 181 



picture screens are also being utilized in eight large cities for dis- 

 playing the "weather forecasts for the information of the general 

 public. 



The forecast distribution already described does not include that 

 effected through the issue of the daily weather maps. In 1896 these 

 maps were issued at 75 stations, having an annual output of more 

 than 3,000,000 maps. At present the map is printed at 58 stations, 

 having an annual issue of over G,000,000 maps. The decrease in the 

 number of stations issuing the regular station weather map has been 

 brought about through the substitution at many points of a news- 

 paper map, generally ImoAvn as the commercial map. A map of 

 this character was first printed at the Centennial Exposition in 

 1876, and in 1896 it was being published in four papers, having a 

 combined circulation of 110,000 daily. In 1910 a plan for its issue 

 under improved methods was brought to the attention of the press 

 of the country, and the officials of the bureau were urged to make 

 every effort to obtain a wide circulation of the publication by this 

 means. At the end of four months 65 papers were publishing the 

 map, and by the following January 100 dailies were making this 

 an important news item. In July, 1912, the commercial map was 

 being prepared at 91 stations and furnished to 147 daily newspapers, 

 with an annual circulation of 985,000,000 copies. 



At the beginning of 1896 there were 173 storm-warning display 

 stations in operation. The number has gradually been increased, 

 until in 1912 there are 619 stations displaying signals to warn 

 mariners of approaching storms. Twenty-five of the stations also 

 disseminate storm warnings by radiotelegraph to vessels at sea. 



FROST STUDIES AND WARNINGS. 



Since 1896, 89 special stations have been established in the fruit 

 sections in connection with the study of frost formation and to assist 

 in making more accurate forecasts and frost warnings for mountain 

 orchard districts, cranberry marshes, the northern vineyards, and 

 deciduous fruit sections. Prior to that time frost warnings were 

 based on reports of general conditions only, no data from the fruit 

 districts being available from which the influence of local conditions 

 of topography and air drainage could be taken into account. The 

 extension of this special warning service into new districts is shown 

 in the following table: 



Districts receiving special frost loarnings. 



In 1896. 



Florida. 

 Louisiana. 

 Texas. 

 California. 



In 1912. 



Wisconsin. 

 Ohio. 



New Jersey. 

 Massachusetts. 



