ASTRONOMY. jl 1 J. 



sary, therefore, supposing the Julian intercala.- 

 tion to continue, to suppress three intercalary 

 days in the course of four centuries ; and it was 

 agreed, that this should be done on the three 

 successive secular years, retaining the intercala- 

 ry day on the fourth, by which means the sun, 

 at the beginning of the fifth century, would oc- 

 cupy the same point in the ecliptic, within a few 

 minutes, that he did at the beginning of the first. 



a. The amount of the accuracy thus attained may be 

 more exactly estimated. The annual error a- 

 mounts to .007736, which, in one century, is .7736 

 of a day, and in four centuries, 3d.0944. Of this 

 error, the fractional part 0^.094-4, or nearly 2h 15m, 

 is all that remains uncorrected by the GEEGORIANT 

 reformation, and in this time the sun describes an 

 arch of 5'.| in the ecliptic. The sun, at the begin- 

 ning of the fifth century, will therefore be only 5'.5 

 advanced beyond the point he was in at the begin- 

 ning of the first. 



i>. The reformation of the kalender did not take place 

 in England till the year 1752. The secular years 

 on which the intercalary days are omitted, are 

 1700, 1800, and 1900. 



c. Though this degree of accuracy is sufficient for the 

 purposes of history, and even of astronomy, and 

 may easily be carried farther, by similar mean* 

 adopted in future ages, yet the problem of interca- 

 lating, so that the difference between the computa- 

 tions 



