296 BULLETIN OF THE 



An appropriation for the purpose having been made by the 

 Regents, a large number of observers scattered over the United 

 Slates and the Territories became voluntary correspondents of 

 the Institution. Advantage was taken of the stations already 

 established under the direction of the War, and of the Navy 

 Departments, as well as of those provided for by a few of the 

 States. The annual reports of the Secretary chronicled the 

 extension and success of the system adopted ; and in a few years 

 between five and six hundred regular observers were engaged in 

 its meteorological service. The favorite project of employing 

 the telegraph for obtaining simultaneous results over a large 

 area was at ouce organized; and in 1849, a system of telegraphic 

 despatches was established, by which (a few years later) the in- 

 formation received in Washington at the Smithsonian Institution 

 was daily plotted upon a large map of the United States by 

 means of adjustable symbols. Espy's generalization that the 

 principal storms and other atmospheric changes have an east- 

 ward movement,* was fully established by this rapidly gathered 

 experience of the Institution ; so that " it was often enabled to 

 predict (sometimes a day or two in advance) the approach of any 

 of the larger disturbances of the atmosphere. "f 



Eminently eflScient as the enterprise approved itself, increasing 

 experience served to demonstrate the increasing demands of the 

 service; and it was seen that to prosecute the subject of meteor- 

 ology over so large a territory, with the fulness necessary, would 

 require a still larger force of observers, and a greater drain upon 

 the resource.s of the Institution, than could well be spared from 

 other objects ; and as the great value of the system was fully 

 recognized by the intelligent, the propriety of maintaining a 

 meteorological bureau by the national support was early pre- 

 sented to the attention of Congress. This most important depart- 



station within every hundred square miles of the United States ; and he 

 sagaciously pointed out that " When the magnetic telegraph [then an 

 infant three years old] is extended from New York to New Orleans and 

 St. Louis, it may be made subservient to the protection of our com- 

 merce." Tills interesting letter was publishe'l in full as "Appendix No. 

 2," to the Report. In 1848, a paper was read before the British Associa- 

 tion by Mr. .John Bail, "On rendering the Electric Telegraph subservient 

 to Meteorological Research : in which the author suggested tliat simulta- 

 neous observations so collected, might reveal the direction and probable 

 time of arrival of storms. (^Report. Brit. Assoc. Swansea. Aug. 1848. 

 Abstracts, pp. 12, 13.) 



* Franklin is said to have heen tlie first who stated the general law, 

 that the storms of our Southern States move off to the northeastward 

 over the Middle and Eastern States. 



f Smithsonian Report for 18t;4, p. 44. An interesting and instructive 

 resume of results accomplished within fifteen years was given in this Re- 

 j'ort, pp. 4i-4j : and continued in the succeeding Report for 18(35, pp. 

 50-59. 



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