92 Mr. Ivory on the Theory of the Astronomical 'Ref r actions » 
which, on account of the smallness of y*', will be a minute 
fraction of a second. 
Rejecting the six foregoing terms, we may assume 
Qg = Hy e’’ + Hg e" + &c. : 
and, having computed the differences in the following table. 
A 2 
A 4 
A 6 
A. 
A 3 
-•0595755 
+ •0278859 
-•0175110 
A 5 
+ •0873930 
-•0177390 
-•0199864 
A 7 
+ •0748672 
+ •0065865 
-•0079396 
Ap 
+ •0446024 
+ •0109256 
— •0002312 
An 
+ •0209241 
+ •0073251 
+ •0016762 
Ai 3 
+ •0081714 
+ •0034934 
+ •0012515 
An 
+ •0027438 
+ •0013379 
+ •0005925 
An 
+ •0008096 
+ •0004339 
+ •0001891 
^19 
+ •0002133 
+ •0001224 
A.. 
+ •0000509 


we shall have 
H 7 = - 4 a 7 -h|^A 7 +^A 2 A 5 +^A 4 A 3 -f-^A 6 A,=- 0486 l 
Hy = — 4a9-f^Ay f y^A 2A7 A4 A5+-^ A*5 A, =*07()9l 
Hii=— 4 an+^Aii + -j^ A 2 A 9 + ^ A"* A® A 5 =-04469 
Hi 3= —4 ais+^Ais-f-^ a® Aii+-^ A^ A,-j- A®A7 =-00249 
Hi 5 = “4 aj.s+Yg Ai 5 -j j^A^ A , 3 -f- ^ A^ Au-j- A® Aq = — -02230 
Hi 7= -4a,7+^A,7+^A«A,3V^A4Ai3+^^| A® Ah= --02558 
Q1 21*^ 175 12'^ 
H^y= -4a,9+^Ap+^A^- A.7+^A4A,3+ 4^A« Ai3 = -01835 
Hai= — 4a2i+^ A 21 + A'^ Aj9+-^A‘‘Aiy-j- A® A 15 = — -01023 
Ho3= — 4 ao 3 -|-^-g A23+-jg A 2 A21+ ^ A^ Ai 9 +-~ A® Ai7 = —-00487. 
The coefficients of the assumed series being found, and being 
expressed in seconds of a degree, the part of the refractions 
depending on Qy will be as follows: 
