210 Mr. Herschel’s and Mr. South’s observations of the apparent 
2 Bootis continued. 
Distance. 
1780.67 ; 4" + ; H. if- diameter, with 222 (estimation.) 
1780.69 ; 3.38 ; H. Catalogue of 1782, single measure. 
1804.25 ; 6 + ; “ Too far to estimate by diameters. The small star is now farther 
“ off than formerly. It is farther off than in w Bootis, which 
“ is in the 3rd class, though | is in the second.” H. “ Account 
“ of Changes,” &c. ;” it is 6". 
1822.63 > 8. 696; H. and S. ut supra, mean of 18 measures. 
1 823.30 ; 6 .667 ; Amici. Letter to Baron de Zaoh, Corr. Ast. viii. p. 216. 
If we lay down the distances and angles here given on a 
scale (with the exception of M. Amici’s, which is evidently 
much too small ; indeed all his measures hitherto published, 
appear to err more or less on that side), the apparent relative 
orbit of the small star ss's", will be found not to deviate 
much from a strait line, the slight degree of concavity to- 
wards the large one observable in it (See fig. i , Plate IV.) 
being not to be depended on, on account of the uncertainty 
of the estimation on which the distance of 6" depends. 
Moreover the motion in it will be found to be not far remote 
from uniformity. The position ss' and s' s 1 ' being in the ratio 
of 18 to 24, and the times in that of 18: 22. The obvious 
conclusion therefore is, that the two stars are unconnected, 
and the relative motion merely the difference of their proper 
motions ; If so, both stars must have a considerable proper 
motion, for the large one (according to Piazzi) has one 
which alone would carry it in the sp direction, at an angle of 
about 40° from the parallel (and therefore almost directly 
away from the small star, at the rate of about 0^.30 per an- 
num.) This would explain the increase of distance, but not 
the angular motion. To explain both it becomes necessary 
