SOLAR AND STELLAR PROPER MOTIONS. 
159 
were ascertained to be, in right ascension, 273° 21' and in 
declination, +27° 19'. At the same time the annual, an¬ 
gular motion of the solar system, as seen from a sixth mag¬ 
nitude star, was found to be 0 // .43642. 
The principal results, derived from the laborious compu¬ 
tations undertaken during the last hundred years to de¬ 
termine the position of the solar apex, as well as the velocity 
of the solar motion, are collated in the following table. In 
some cases, the epoch for which the computation was made? 
is omitted in the original papers, and in others it is indefinite. 
Only those are given in the table about which there is no 
doubt. The date given, is the time of publication. 
The values of the solar motion given by Herschel and 
Airy were considered by the authors themselves as of little 
weight. Rancken’s value is indeterminate. The mean is 
given of the seven other determinations. 
The values found by 0. Struve and by Dunkin were for 
the distance to first magnitude stars, that by L. Struve for 
the distance to sixth magnitude stars, while the values given 
by Stone and Bischof were for the mean distances of the re¬ 
spective groups of stars used by each author. 
But little importance is attached to the means of the coor¬ 
dinates of the solar apex, for it is impossible to assign proper 
weights to such data. 
It is intended to give each determination as deduced by 
the author and, in the means, equal weight is given to the 
separate values. 
18—Bull. Phil. Soc., Wash., Vol. 11. 
