46 



SCIENCE. 



[N. S. Vol. XXI. Xo. 524. 



of the hour bids us look forward with cheer- 

 ful optimism. 



R. S. Woodward. 



THE AMKinCAX ASISOCIATIOX FOR THE 

 ADVAXCEMENT OF SCIENCE. 

 THE I'RESEXT .STATE OF GEODEHY.'' 



The problems of geodesy, like those of 

 most sciences, enter upon new phases with 

 the accunuilation of facts bearing upon 

 them. The problem of determining the 

 amount of the earth's compression was 

 added to that of determining the size of 

 the supposed sphere as soon as Newton had 

 demonstrated its oblateness. The contro- 

 versy to wliich Newton's theory gave rise 

 was settled by the famous geodetic opera- 

 tions of the eighteenth century which fur- 

 nished the cardinal facts in regard to the 

 earth's figure and size. 



What may be regarded as the slow prog- 

 ress of a more precise knowledge of the 

 earth's dimensions since that time must be 

 attributed to the difficulties inherent in the 

 problem. 



In the first place the dimensional meas- 

 urements must necessarily be confined to 

 the continental areas which occupy but 

 three elevenths of the earth's surface. The 

 configuration and relationship of these 

 areas make it impossible to girdle any sec- 

 tion of the earth by direct measurement. 



Secondly, the admeasurement of these 

 areas is far beyond the reach of individual 

 enterprise and can only take place when 

 the practical needs of governments suggest 

 the utility of great mensurational surveys 

 which at the same time and without great 

 additional expense will furnish the data 

 required for a more perfect knowledge of 

 the spheroid. In making this statement 

 it is not forgotten that individuals and 

 governments did undertake in all ages 



* Addrpss of the vicc-presWcnt and (■hainiiaii of 

 Spcfion A — ^fatliP7iiaties and Astronomy, Amer- 

 ican Association, Pliiladelpliia, December, 1904. 



measurements for the purely scientific pur- 

 pose of determining the size of the earth, 

 for the desire for knowledge on this sub- 

 ject may be reckoned coeval with intellec- 

 tual development of man. 



Happily it may be said also that by their 

 collective action the governments of the 

 world have shown in recent times that it is 

 considered a governmental function to sup- 

 port and promote researches in this bi'anch 

 of science. I allude, of course, to the ex- 

 istence of the International Geodetic Asso- 

 ciation. It will not be out of place to say 

 in this connection that the association exists 

 by virtue of a formal convention between 

 the participating governments, which are, 

 at the present time, the United States, 

 Japan and Mexico and all the European 

 nations save Portugal. Roiunania and the 

 group south of the Danub*. No account 

 of geodesy would be complete that failed 

 to consider the aims and labors of this asso- 

 ciation. Its history is part of the history 

 of geodesy since 1861. At that time it 

 began its career as the ]\Iittel Europaisehe 

 Gradmesung. In a few years it expanded 

 into an European association and in 1886 

 it became international. 



It is not generally known that it was this 

 association which instigated the French 

 government to invite the world to establish 

 an international bureau of weights and 

 measures at Paris. Without detracting in 

 any way from the labors of Bessel, Clarke 

 and others in intercomparing geodetic 

 standards, the successful labors of the 

 bureau which in consequence was estab- 

 lished in Paris removed at least some of 

 the difficulties that were encoimtered by 

 the investigators in this branch of science, 

 and by those engaged in the practical work 

 of the measurement of the earth. 



The history of geodesy is full of in- 

 stances of confusion and wasted energy diie 

 to the lack of a common standard, and the 

 results of many arc measures which would 



