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V. On the changes which have taken place in the declination of 
some of the principal fixed Stars. By John Pond, Esq. As- 
tronomer Royal, F. R. S. 
Read April 18, 1822. 
The mural circle having in September last been put into 
complete repair, and declared by Mr. Troughton to be in as 
perfect a state as when first erected, I resumed my examina- 
tion of the principal fixed Stars which form the Greenwich 
Catalogue. In the course of a very short time, I found that 
several anomalies, which had previously given me much per- 
plexity, still subsisted : some of these were of such a nature 
as to lead to a suspicion that a change might possibly have 
taken place in the figure of the instrument ; on the other hand, 
there were circumstances, that strongly militated against such 
a supposition. 
Several of the stars in which the supposed discordance ap- 
peared the greatest, passed over almost the same divisions 
with others, in which no such discordance could be perceived. 
Moreover, in examining these discordances in different points 
of view (that is, both with respect to their right ascensions 
and polar distances) I fancied I perceived something like a 
general law, that was quite incompatible with any possible 
hypothesis of error in the instrument. 
On a point of this importance, I clearly saw the necessity 
of devising some new method of observation which might 
