WEATHER BUREAU. 95 



LIBRARY. 



During the fiscal year 1,130 books and pamphlets were added to 

 the library, the total strength of which is now well over 41,000 vol- 

 umes. Most of the gaps in periodical publications occasioned by the 

 war have now been filled, the chief exceptions being Russian publica- 

 tions. A nearly exhaustive bibliography of the climatology of South 

 America was published in October. The various catalogues have 

 been kept up to date. One of these, not mentioned in any previous 

 report, is a catalogue of portraits of meteorologists. This has been 

 in progress for several years and is probably the only one of its kind 

 in existence. At least one additional trained assistant is greatly 

 needed, in order to enable the library to undertake important work 

 outside of routine. 



MARINE METEOROLOGY. 



The marine meteorological work progressed satisfactorily during 

 the year. A larger amount of data was furnished the Hydrographic 

 Office for publication on the Pilot Charts, and at the same time an 

 increased volume of material of value to marine interests was sup- 

 plied through publications of the bureau. 



During the year arrangements were perfected for an interchange 

 of marine reports with the French meteorological service. 



The amount of data furnished for use in admiralty cases was about 

 the same as in previous years. 



It was possible near the end of the year to augment the force en- 

 gaged on the marine work at Washington, where a reduction had 

 been necessary during the preceding year. A further increase of this 

 force is needed to make greater use of the material now being re- 

 ported by observers, and which supplies the fullest record we have 

 of detailed weather conditions over the Northern Hemisphere. 



The volume of reports reaching the bureau still reflects the de- 

 pressed state of shipping, but shows, nevertheless, the continued in- 

 terest of seamen in the marine meteorological work. 



^In' 



Reference to the increasing use of radio at sea and its influence on 



'fe 



the transmission of weather information will be found elsewhere. 



INSTRUMENT DIVISION. 



The maintenance of the instrumental and storm warning equip- 

 ment of the Weather Bureau, which has an estimated value of 

 $700,000, together with the purchase of necessary new equipment, 

 has been accomplished at an expense of about $26,000. Station 

 officials have cooperated with the division by making diligent effort 

 to keep down expenses without permitting the equipment to 

 deteriorate. 



The major portion of the work of repairing instruments, includ- 

 ing the rebuilding of special thermographs for fruit-frost investi- 

 gations, has been performed in the instrument shop, and important 

 progress has been made in the development of new forms of appa- 

 ratus and instruments, 



A new form of solar radiation receiver, utilizing the principle of 

 thermo junctions, was worked out with the joint efforts of several 



