[ 346 ] 
Therefore aftronomers have not converted the equa- 
tion of right afcenfion into time according to the 
motion of the Primum Mobile j for, the equation of 
time being mean folar time, and the motion of the 
Primum Mobile being compleated in 23 H. 56 M. 
4 S. of mean folar time, therefore 15 motion or 
the Primum Mobile does not anfwer to 1 hour of 
mean folar time (though it does to 1 hour of fidereal 
time) but to the 24th part of 23 H. 56 M. 4 S. or 
59 M. 50 4 S. And it appears, that the equation of 
time in the Connoifiance des Mouvements Celeftes 
has been computed in this manner, and the table in 
the 79th page of the Connoiftance for 1761 has been 
made ufe of, entitled, “ A table to convert into de- 
<c grees the time of a clock regulated according to the 
“ mean motion of the lun.” 1 he degrees of this ta- 
ble are evidently degrees of the Primum Mobile, 
1 hour of mean folar time giving 15 2' 27,8 , 
which anfwers to the motion of the ftars from the 
me idian, but not to the mean motion of the fun from 
thence, which is 15 to 1 hour of mean folar time: 
whence it appears, that this writer hath evidently 
fell into the miftake of taking motion or (pace of the 
Primum Mobile, inftead of the mean motion of the 
fun from the 'meridian ; an equal miftake to that of 
which he erroneoufly fuppofes former mathemati- 
cians to have been guilty, in computing the equation 
of time. So that the equation of time in this ephe- 
meris, beftdcs the miftake arifing from the taking 
in the equation of the equinoctial points into the 
account, is conftantly too fmall in the proportion of 
24 hours to 23 H. 56 M. 4 S. or ot 366 to 3 l) 5 ,> or 
too fmall by 1 fecond upon every 6 minutes ol the 
equation 
4 
