The National Geographic Magazine 



for correction, or disallows, under the 

 Superintendent's direction, all items of 

 expenditures irregular in form or jn con- 

 travention of law or regulations, and 

 refers to the Comptroller of the Treas- 

 ury for decision all questions of law in- 

 volving a payment to be made by him. 

 The editor, reporting to the Superin- 

 tendent, compiles the administrative 

 part of the annual report and acts as 

 editor in connection with all other pub- 

 lications of the Survey except the 

 charts. 



THE EXTENSION OF FIELD WORK 



The acquisition of Florida and Oregon 

 in 1819 and of Texas and California 

 soon after the reorganization of the 

 Survey before described vastly extended 

 the operations, and in view of the de- 

 sirability of connecting the surveys of 

 the Pacific and Atlantic coasts, a trans- 

 continental triangulation was authorized 

 in 1 87 1. Eight years later, in recogni- 

 tion of one of its functions, the name 

 of the organization was changed to that 

 of Coast and Geodetic Survey. « 



When Alaska was purchased in 1867 

 the charting of its vast and intricate 

 shore line was added to the duties of the 

 Survey, and still more recently, in con- 

 formity with and in pursuance of the 

 established policy, its labors were ex- 

 tended, to use the phraseology of the 

 law, to all " the coasts under the juris- 

 diction of the United States, ' ' in order to 

 include Porto Rico, Hawaii, Guam, the 

 Samoan Islands, and the Philippines. 



The plan of reorganization contem- 

 plated a chain of triangles along the 

 coasts which should unite and coordi- 

 nate all the local surveys. Astronomical 

 observations were to fix the geographical 

 position of the triangulation, and the 

 differences of longitude between some of 

 principal stations and Europe were to tje 

 determined. 



The topography was to be carried in- 

 land as far as would subserve the pur- 



poses of commerce and defense, and, 

 resting upon the data thus obtained, 

 soundings were to be made along the 

 shores and seaward to insure the safety 

 of commerce. Such was the simple 

 scheme, but there were inherent in it 

 certain requirements for the accomplish- 

 ment of which extended researches in 

 many branches of science were needed, 

 and there were inherent in it also possi- 

 bilities for greater usefulness to the na- 

 tion and the world than the mere attain- 

 ment of the immediate objects sought. 

 It was foreseen that the triangulation 

 if carried out with sufficient care would 

 ultimately form the basis of a national 

 trigonometric survey. The great ex- 

 tent of territory to be covered indicated 

 that the triangulation would be used to 

 determine the size and figure of the 

 earth, which is the ultimate base of di- 

 mensional astronomy. The need of 

 compasses on. the charts compelled the 

 determination of at least one of the 

 elements of the earth's magnetism and 

 a study of the law of its variation. The 

 rise and fall of tides required observa- 

 tions along the coasts which would dis- 

 close the law of their periodicity in order 

 that predictions could be made long in 

 advance; a needful regard to bench- 

 marks to which the tides were referred 

 would betray the subsidence or rise of 

 the land. Observations on tidal and 

 ocean currents were needful to supple- 

 ment the other information on the 

 charts. The determination of astro- 

 nomical positions required the perfec- 

 tion of existing star places, and thus 

 practical astronomy was stimulated, and 

 when the importance of the geodetic 

 function of the Survey was recognized 

 by law, the pendulum, by means of 

 which the figure of the earth can be 

 determined, was employed in gravity 

 research. 



Deep-sea soundings and incidental 

 physical observations and dredgings 

 contributed no little to our knowledge 

 of marine life. 



