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nox A will come to the meridian at the fame inftant 
Oi abfolute time, as if the pole had not been 
tranflated from P to Qj and the difference of time 
between the lun S coming to the meridian, and a 
fiidfitious fun U, fuppofed to move uniformly in the 
equator, with a motion equal to the fun’s mean mo- 
tion in longitude, or the equation of time will be there- 
fore meafured by A Q^S ' — > A P U, the difference of 
their right afcenfions reckoned from the fame point 
A. It will alfo, by the like reafoning, be meafured 
by B ^ B P U, the difference of their right afcen- 
fions reckoned from the fame point B ; for B being 
the equinox, when the pole is at Q, the abfolute 
time of the point B palling the meridian of any 
place will remain the fame as if the pole had conti- 
nued at P j whence the propofition eafily follows, in 
like manner as above. 
It may be now proper to fhew how the equation 
of time, as affected by the nutation of the earth’s 
axis, ought to be computed. This may be done two 
ways. The « firfl follows from what has been julf 
“ laid down : correct the mean right afcenfion of 
“ the fun U P A, by the precefhon of the equinoxes 
“ in right afcenfion APB (which is always to the 
preceffion in longitude B A, as cofine of the obli- 
“ quity of the ecliptic, to the radius, or as 12 to 
“ 13 nearly) the difference of the fun’s mean right 
“ alcenfion thus corredf ed B P U, and the fun’s appa- 
“ rent afcenfion B QS, turned into time, is the true 
“ equation of time.” 
Otherwife the effedt of the nutation of the earth’s 
axis upon the equation of time, if thought defend- 
ing notice, as it can never exceed 1. of a fecond of 
time, 
