Miri'KOK'ol.odlCAl. WOKK OF SMITHSONIAN INSTITUTION. {)1 



ili icct 1 licir operators ((> i-e[)I;icc in tln-ir i<\iiular iiioiiiiiii; disjialclies 

 Hie signal, "•(). K.,'' by wliicli they wciv. acciistoincd to ainiouiicc that 

 tlicir lilies were in order, by sncli words as "fair." '•cloudy/' etc., thus 

 .iii\iii.U. without additional trcuible, and as coiu'isely as possible, a suin- 

 niaryofthe condition of the weather at the ditfeient stations, which 

 slionld be comnuinicated to liinu This request was coini)lied with, and 

 such elementary telegraphic Aveather re])()rts were thus furnished the 

 Institution daily, without charge. This action of ]*rof. Henry, which 

 has sometimes been erroneously ascribed to Prof. Espy, was the be- 

 ginning of telegraphic weather service, nothing of the kind having 

 been attemi)ted in Euro])e until a later date, and by means of these re- 

 ports ])redictions of coming storms, with all the Jiow recognized advan- 

 tage to the country at large, were juade possible. With the material 

 thus obtained the Institution was enabled in LS.")!), to construct the hrst 

 current weather map, gi\'ing daily, from "live data," the meteorological 

 conditions over the whole cimntry. This ma]) was hung where the pub- 

 lic <'ould have g<Mieral access to it to observe the changes, and its indi 

 cations were tirst published at large by signals displayed from the high 

 tower of the Institution. This method was followed, and further ex- 

 tended, by publications in the Washington Eroiiiuj t^iar in ISoT, and 

 such general interest was manifested in the subject that telegraphic 

 weather rei)orts were thereafter furnished to the yHtar for daily publi- 

 cation. The systematic notification of the general i)ublic by the press 

 and otlierwivSe of Aveather observations, api)ears, then, to have been 

 undoubtedly due to Henry, and unquestionably to have preceded by a 

 year a similar j)ubIication in 1858, of Leverrier, to whom this pioneer 

 step has been erroneously attributed. 



In 1858, the meteorological inap already in use was improved by the 

 adoption of circular disks of different colors, which were attached to it 

 by pins at each station of observation, and indicated by their color 

 the state of the atmosphere — white signifying clear Aveather; gray. 

 cloudy; black, rain, etc. The disks had an arrow stamped u])on them, 

 and as they AA'cre so arranged that they could be attached to the map in 

 any direction, the motion of the Avind at each station was shown by them, 

 and the ''probabilities'' thus more accurately forecast. 



The study of the meteorological data, begun in 1849, continued under 

 the direction of the Institution fm- twenty-five years, during which tinu' 

 numerous publications were issued relative to temperature, rainfall, 

 hygrometry, and casual phenomena, Avhile i)oi)ular information was con- 

 tinuously disseminated by publishing telegraphic weather reports, maps, 

 etc. Ajnong the associates of the Institution in this branclj of investi- 

 gation may be mentioned I*rof. J^vspy, and later. Prof. J. H. Coftin, Mr. 

 C. A. Schott, ami others. Their Avork may be concisely <lescrib(^d as 

 follows: Prof. Espy utilized the already collected data in the prepa- 

 ration of his Third an<l Eourtli Meteorological Reports. After the 



