DEPARTMENT OF MERIDIAN ASTROMETRY. 



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Two supplementary investigations are under way. One is a test of 

 the larger groups for a possible difference between galactic and extra- 

 galactic stars. The other is to divide the general group, and possibly 

 the larger groups A and K, according to amount of proper-motion. 

 It may be that the range from to 20" per century is too wide to be 

 properly included in a single group. 



Table 2. 



SAN LUIS DECLINATIONS. 



Mr. Roy has completed a preliminary discussion of the San Luis 

 declinations. After applying all known instrumental and personal 

 errors, mean latitudes were formed for progressively increasing declina- 

 tions and for each observer in the four combinations of the two circles, 

 clamp east and clamp west. Since the Pulkova refractions were em- 

 ployed in the reductions, it was to be expected that the resulting lati- 

 tudes would exhibit a residual refraction term, owing to the elevation 

 of the station at San Luis. From the residual latitudes a tangent 

 term was computed, as in table 3. 



Table 3. 



The tangent term was then applied to the mean latitudes, producing 

 a very fair agreement. 



Certain pecularities are to be noted, however. Table 3 shows large 

 constant differences. The differences in mean latitude among the 



