3 
and positions 0/ 458 double and triple stars , 
presented to public view, the mean result of each night’s 
work is here noted ; but as the number of observations, and 
the differences between the extreme measures of each series 
are also specified, it is hoped that the alteration will be satis- 
factory to the Society. 
As in these observations I have not had the powerful aid 
of Mr. Herschel, it has been my endeavour as far as possible 
to compensate for the loss ; hence, instead of taking ten indi- 
vidual observations both of distance and position on the same 
night, and thereby considering the star measured, I have 
divided the work generally assigned to each star between 
two evenings, the better to correct any error which unfa- 
vourable state of atmosphere, inaccurate micrometrical read- 
ings, or particular bias of judgment might entail; and when 
the results have exhibited discordances greater than seemed 
justified by the difficulty of the observations, a third, or even 
a fourth night’s determination has been found useful. 
To the observations contained in the former Memoir, pecu- 
liar interest was attached by the comparison of them with 
the results obtained by other astronomers ; of which by far 
the most important were those derived from the labours of 
Sir W. Herschel ; but as the observations which are re- 
corded in the Philosophical Transactions are (from circum- 
stances before * adverted to ) of themselves inadequate to 
furnish the final results arrived at by that illustrious astro- 
nomer, it is grateful to me, and doubtless will also be to the 
Society, that the kindness of Mr. Herschel has supplied the 
necessary information ; thus the existence of fresh connected 
systems is substantiated, and adegree of present importance con- 
ferred on the following pages, which he alone could bestow. 
* See Phil. Trans, for 1824, Part III. page 20. 
