186 



CARNEGIE INSTITUTION OF WASHINGTON. 



In the following table the first column indicates the spectral type 

 according to the Harvard classification. Column 2, headed R. A., 

 gives the right ascension, and column 3, headed D, gives the declination 

 of the solar apex as derived from the separate solutions by type. The 

 last column, headed V, indicates the velocity of the sun's motion as 

 derived by Campbell for each separate type. 



As can readily be seen, the results for the K and M types and those 

 for the A and F types are closely similar, but the two groups are 

 distinct. In other words, there seems to be some peculiarity in the 

 systematic motions of the early type stars as represented by the A 

 and F types, quite at variance with the systematic motions of the 

 later types, as represented by the K and M types. The B-type stars, 

 though an early type, have such small real velocities that any sys- 

 tematic peculiarity in their motions would have but little effect upon 

 the determination of solar motion. It is, therefore, not surprising 

 to find the solar motion as derived from this type closely approxi- 

 mating the general solution for all types. 



There may be some significance attachable to the fact that the 

 apices as given in the table are very nearly distributed along a 

 parallel of approximately 21° galactic latitude. 



The G-type stars, as previously stated, give an anomalous result. 



A number of star groups have been collected where there seems to 

 be a possible community of motion, but where the proper-motions 

 are so small as to render it impossible to determine a convergent 

 point by their means. These groups have therefore been recom- 

 mended to the spectroscopist for attention. 



In the case of a number of these groups a mean value for the 

 proper-motion of each group has been taken, and their directions of 

 motion plotted with a view toward uncovering any possible system- 

 atic motion among stars of small proper-motion. As a result, four 

 groups have been found with a common intersection at about right 

 ascension = 4^ 45"" and declination = — 15°. While the effect may 

 be the result of chance, the rather sharp convergence would seem to 

 indicate causal connection. 



Another investigation dealing with stars of large proper-motion, 

 20 seconds per century or more, is being pushed. This subject has 



