Mr. Gkoombridge*s further Observations 
Mean Refraction. 
Zen. 
dis. 
French 
tables. 
S. G. 
Value of y. 
e 
/ n 
8o 
5 * 9-8 
5 19.18 
3-63429 
8i 
5 53*5 
5 52-83 
— 
82 
6 34-4 
6 33 79 
— — 
83 
7 247 
7 24-63 
84 
8 29.9 
8 29.13 
— — 
85 
9 54-3 
9 53-03 
■ — — 
86 
II 48.3 
11 4527 
87 
14 28.1 
14 19.80 
3-63429 
88 
18 22.2 
18 19.83 
3-35709 
89 
24 21.2 
24 32-94 
3.07989 
90 
33 46 3 
34 28.13 
2.80269 
The two formiilse compared. 
Zen. 
dis. 
3 362 sr 
X 
58". 1 192 
3-63429^ 
X 
58".! 32967 
0 
/ n 
/ « 
70 
2 38.41 
2 38-34 
71 
2 47 - 3 > 
2 47.23 
72 
2 57-J3 
2 57-03 
73 
3 8.04 
3 7-92 
74 
3 20,22 
3 20.07 
75 
3 33-92 
3 33-73 
76 
3 49-44 
3 49-21 
77 
4 7-^9 
4 6.89 
78 
4 27.68 
4 27-30 
79 
4 5 * 59 
4 5«-09 
80 
5 1985 
5 *918 
81 
5 53-74 
5 52.83 
82 
6 35.06 
6 33 79 
83 
7 26.46 
7 24.63 
84 
8 31.85 
8 29.13 
85 
9 57-27. 
9 53-03 
86 
11 52.21 
11 45.27 
87 
H 3»-75 
14 19.80 
88 
18 19.19 
18 19 S3 
