Mr. Ivory on the Theory of the Astronomical Refractions, 91 
+ |^A,+^(A3-4Ai) + ^(A,-6A3+15Ai) 
305 , 905 1 
- 48+^" 
The next three terms are as follows : 
4 aj + jg ^i) + (A 5 — 4 A 3 + 6 Aj) 
+ S' + S+ S ^ 
^_ 4 ag+ |iAa + ^ (A 5-2 Ag + A,) 
+ ^(A,-4Ag+6Ag-4A,) 
I QK 
+ ^(A9-6A7 + 15A5-20A3+15Ai) 
125 125 
4.8 IF 
^ 
+ 4^5+ — A 5 + (A 7—2 A 5 + Ag) 
+ -^ (A 9 — "I A 7 + 6 A 5 — 4 ? Ag+ Ai) 
125 
+ 4^(An-6A9 + 15A7-20Ag 
+ 15 Ag-6 AJ 
125 125 
•+ - 4 - C ^ 
48 ^ 48 
■} 
On substituting the exact values of Aj , Ag , &c., these three 
terms will come out as follows : 
, 158 
348 
_ c—^ . 
+ 
5 
8891 
75 
or + -00239 . e 
or — *00316 . 
c~^ . or + *00538 . e^. 
These three terms are the part of the refraction that depends 
on the height of the atmosphere : at the horizon, or when 
e = 1, their amount is greatest and equal to 
f x-fiomi =/'x726"’7x -00461 =/'x3"-3, 
^ o z 
