352 PROCEEDINGS OF THE AMERICAN ACADEMY 



by him close enough is somewhat doubtful ; there seems, however, to 

 be no doubt that an interpolation between Bradley and the modern 

 catalogues to the epoch of Struve's earlier work would give on the 

 whole somewhat greater right ascensions of the stars of my list than 

 Struve himself, even after the systematic corrections used by Arge- 

 landoi', which arc derived from adopted positions of the clock stars, 

 were applied. 



In other words, the distribution of the early observations of any 

 given polar is apt to be so irregular that any least-square solution will 

 give somewhat uncertain results; and it will not be soon possible to 

 arrange a really normal catalogue for these, any more than for other 

 needed stars ; a difficulty which in this case is aggravated by the small 

 number of those objects in the critical positions which have been fre- 

 quently enough observed. 



