ASTRONOMY 51 



the "arc of Peru," that arc which when measured by 

 French astronomers in an earlier century afforded the 

 first practical proof of the ellipticity of the earth. The 

 same scale of achievement is seen in the work of precise 

 leveling conducted by LALLEMAND and his associates, 

 repeating and extending the earlier work of BOURDALOUE. 

 The French have been very active in developing the 

 application of wireless telegraphy in longitude deter- 

 minations. This is illustrated by their observations 

 between Paris and Poulkovo, Paris and points in Al- 

 geria, and culminating in the Paris- Washington campaign 

 of 1913. 



Observational Astronomy. France has equipped many 

 observatories where work is being conducted, following 

 carefully prepared plans, well organized, and actively 

 executed. The long series of publications from these 

 institutions Paris, Bordeaux, Nice, Abbadie, Toulouse, 

 Meudon, Besangon, Marseille, Lyon, Algiers bear 

 ample testimony of their fruitfulness. In the field of 

 observations of position, the most notable among 

 many excellent star catalogues is that of the Paris Ob- 

 servatory, in eight volumes. BOSSERT'S catalogue of 

 proper motions is important in any work dealing with 

 stellar motion. Double stars have been actively observed 

 at Toulouse and by JONCKHEERE, who made many and 

 important discoveries in this field, at the Observatoire 

 d'Hem and later at Lille. In the discovery of celestial 

 bodies the French observers present about sixty comets, 

 about 1 80 asteroids, and many nebulae. Here the 

 names CHARLOIS, CHACORNAC, COGGIA, PERROTIN, the 

 brothers HENRY, STEPHAN, BORRELLY, TEMPLE, GIACO- 

 BINI, QUENISSET, and others, are familiar. In photo- 

 metric work the numerous and careful observations of 

 LUIZET are of especial value. 



