[ 70i J 
globe of the earth by the actions of the fun and moon, 
and have endeavoured to determine their precife 
quantity and laws of variation. You obferved your- 
lelf, that the fuppofition you made ufe of, of the 
earth’s pole moving round the periphery of a circle, 
whofe center reprefented the mean place of the pole, 
was not exadt : and in effedt, as theory (hews there are 
two equations arifing from the fun’s adtion, and as 
many from the adtion of the moon, to be ufed in 
fettling the true place of the pole, the fimple motion 
in the circle cannot anfwer accurately to the compo- 
fition of thefe feveral motions ; and it is from thence 
proceeded that furprizing difference you found be- 
twixt the polar diltances calculated on that fuppofi- 
tion, and thofe obferved, in the flar a, Cajjiopea , in 
the year ij 38, and in ti ttrfse majoris in the year 
174,0 and 1741 ; which diltances, if computed from 
the theory, as here laid down, agree with the obfer- 
vations as nearly as the others. This appears in the 
tables that are added of thefe computations. You 
alfo inhnuated it would be proper to examine, whe- 
ther the pofition of the moon’s apogee had not a 
fhare of influence in thefe apparent motions of the 
ftars. I therefore confidered that point, but found, 
as you will fee in the fifth proportion, that the di- 
minution of the moon’s adtion in the higher part of 
its orbit is fo compenfated by the increafe of the 
fame adtion in the lower part, that in the whole re- 
volution of the moon no alteration arifes, whatever 
be the fituation of the nodes. 
The fecond elfay is a Theory of the Irregularities, 
that may be occafioned in the annual Motion of the 
Earth by the Actions of Jupiter and Saturn. I was 
Vol. 49. 4U led 
