CHANGE OF THE SUNS DECLINATION &CC 27 



¥ 



Example. 



Suppose the following equal altitudes were taken in latitude 39°. 5 6>. 

 N. token the sun's longitude was 4 s . 15°. 



A. M. S h . 32' 20"— P. M. 3" 32' 24* 



Add 12 



15 32 24 



Deduct forenoon's observation 8 32 20 



2J ~7 4 " 



half interval ;... 3 30 2 



Add forenoon's observation 8 32 20 



Sun's center on the meridian nearly 12 2 22 



FOR THE CORRECTION. 



The sun's declination answering to 4 s 15* of his longitude 

 is nearly 16° 21', and the change of declination at the same 

 time about 16' 55" in 24 hours, or 2' 28" during the half in- 

 terval. 



THEN BY THE RULE. 



Change of declination during 



half interval 2' 28" P. L. 1 1. 8631. 



Horary angle 52° 30' log. cosec. — 10. 1005 



1. 7626 

 Latitude 39° 56" log. cotan. + 1 0. 0772 



P. L. 1. 8398= 2' 36"= I0"24 , "in 



time, being the first part of the equation, and additive by the 

 rule. 



