TABLES 84-85. 

 LENGTH OF THE SECONDS PENDULUM. 



TABLE 84. Length of Seconds Pendulum at Sea Level for Different Latitudes.* 



107 



TABLE 85. -Length of the Seconds Pendulum. 4 



1 Laplace ? " Traite de Mecanique Celeste," T. 2, livre 3, chap. 5, sect. 42. 



2 Mathieu : " Sur les experiences du pendule ; " in " Connaissance des Temps 1816." 

 Additions, pp. 314-341, P- 332. 



3 Biot et Arago: " Recueil d' Observations geodesiques, etc." Paris, 1821, p. 575. 



4 Sabine : " An Account of Experiments to determine the Figure of the Earth, etc., by 

 Sir Edward Sabine." London, 1825, p. 352. 



5 Saigey: "Comparaison des Observations du pendule a diverses latitudes; faites par 

 MM. Biot, Kater, Sabine, de Freycinet, et Duperry;" in "Bulletin des Sciences Mathe- 

 matiques, etc.," T. i, pp. 31-43, and 171-184. Paris, 1827. 



6 Pontecoulant : "Theorie analytique du Systeme du monde," Paris, 1829, T. 2, p. 466. 



7 Airy : " Figure of the Earth ; " in " Encyc. Met." 2d Div. vol. 3, p. 230. 



8 Poisson: "Traite de Mecanique," T. i, p. 377; "Connaissance des Temps," 1834, 

 pp. 32-33 ; and Puissant : " Traite de geodesic," T. 2, p. 464. 



9 Unferdinger : " Das Pendel als geodatisches Instrument ; " in Grunert's "Archiv," 1869, 

 p. 316. 



10 Fischer : " Die Gestalt der Erde und die Pendelmessungen ; " in " Ast. Nach." 1876, 

 col. 87. 



11 Helmert: "Die mathematischen und physikalischen Theorieen der hoheren Geo- 

 dasie, von Dr. F. R. Helmert," II. Theil. Leipzig, 1884, p. 241. 



12 Harkness. 



* The data here given with regard to the different determinations which have been made of the length of the 

 seconds pendulum are quoted from Harkness (Solar Parallax and its Related Constants, Washington, 1891). 

 t Calculated from a logarithmic expression given by Unferdinger. 



SMITHSONIAN TABLES. 



