156 
EASTMAN. 
1167 stars. On the supposition that the irregularities of 
proper motion were entirely due to accidental errors of ob¬ 
servation, he found the coordinates of the solar apex to be 
in R. A. 261° 14'.0 and in Dec. +32° 55'.0. On the suppo¬ 
sition that the irregularities were due entirely to the pecu¬ 
liar motions of the stars, he found the coordinates to be 
263° 43.9 and 4-25° O'.5. On the first supposition he found 
the angular value of the annual solar motion to be 0".3346, 
and on the second supposition 0".4103. 
In 1863, Mr. E. J. Stone 92 using the factors of solar motion 
computed by Mr. Main, in his Catalogue of proper motion 
stars, proposed to test the possibility of determining the 
linear velocity of the solar system, so as to obtain any con¬ 
siderable diminution of the sums of the squares of the cor¬ 
rected proper motion. 
Assuming the linear unit to be the mean distance of the 
group of stars considered, and therefore the distances of all the 
stars to be equal, he found, using the entire number of factors 
computed, the sum of the squares of the uncorrected proper 
motions in R. A. to be 0 S .525 and the velocity of solar mo¬ 
tion to be 0".054. The sum of the squares of proper motions 
corrected for solar motion was 0 s .473. Concluding that the 
small value of the solar motion was due principally to the 
inaccurate factors for stars near the pole, he omitted the data 
for the 13 circumpolar stars and from the remaining 91 
stars, he found, * 
From From 
R. A. Dec. 
The sum of the squares of the uncorrected 
proper motions.0 S .464 48.539 • 
The sum of the squares of the corrected proper 
motions.0 S .381 44.862 
The velocity of solar motion.0".434 0".341 
The author remarks in conclusion, ‘ I think we may fairly 
conclude that, so long as we confine our attention to large 
proper motions, we have numerical evidence of a drift such 
22 Stone, E. J. Month. Not. Roy. Ast. Society, xxiv, 1864; 36. 
