184 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



libraries, and other individuals or institutions interested in the 

 marine meteorological work of the Weather Bureau. 



The charts of the north Atlantic were first published in 1909, with 

 a monthly issue of 3,000, which has since been increased to 6,000. 

 The north Pacific issue in 1909 was 1,500, while the issue at present 

 is 3,100; that of the south Atlantic has been increased from 1,000 to 

 2,230, the south Pacific issue from 1,500 to 2,250, the Indian Ocean 

 edition from 1,800 to 2,250, and that of the Great Lakes from 1,000 

 to 1,200. 



VESSEL-REPORTING SERVICE. 



The Weather Bureau maintains vessel-reporting stations at Block 

 Island, Cape Henry, Sand Key, Southeast Farallon Island, Point 

 Reyes Light, North Head, Port Crescent, and Tatoosh Island, where, 

 in addition to their meteorological duties, the officials are required 

 to report all wrecks, marine disasters, etc., and to transmit com- 

 munications between owners, underwriters, and others interested in 

 marine matters. As an instance of the enormous volume of work of 

 this character done at these stations, it may be mentioned that during 

 the year 1912 the Weather Bureau station at Cape Henry, Va., re- 

 ported 19,876 vessels as having passed that station. 



COOPERATIVE OBSERVATIONS AND CLIMATOLOGICAL REPORTS. 



It was early apparent that only a limited number of telegraphic 

 observation stations were required for forecasting purposes. For 

 establishing and recording the climatic conditions of the country, 

 however, it was necessary that a much wider distribution of observa- 

 tion stations be provided. This gave rise to the establishment of the 

 climatological service of the bureau, which was brought about by 

 enlisting the cooperation of public-spirited citizens in the formation 

 of a widespread system of observations. At first a full equipment 

 of the few scattered stations with standard instruments was not 

 possible, and the results obtained from many of the early observa- 

 tions were unsatisfactory. During the last 10 or 15 years, however, 

 the equipment has been improved until now practically all stations 

 are supplied with accurate and well-exposed instruments. 



In the earlier years this system covered only the older settled dis- 

 tricts, but the observation stations were gradually extended into the 

 far western mountains and valleys, and even into the island de- 

 pendencies and Alaska. At the present time no important area of 

 the country is without the means of approximating its main climatic 

 features. 



During the past 16 years the number of cooperative stations has 

 increased from less than 3,000 to slightly more than 4,000, practically 

 the entire extension having been effected in the trans-Mississippi 

 districts. 



