202 
Mr. Groombridge’s Observations 
Factors for the correction of the Refraction, the mean result 
of 210 observations. 
Thermometer within. Thermometer without. 
Bradiey. 
Observed. 
Equated, 
I Observed. 
Equated. 
31 
-b ,°499 
+ ,0437 
4- ,0436 
24 
-f ,0436 
4 -,° 43 6 
37 
,0336 
,0329 
,02 95 
31 
,0319 
,0289 
43 
,0178 
,0153 
,0155 
38 
,0133 
,0142 
49 
,0025 
,0000 
,0014 
45 
,0007 
—,0003 
55 
—, 012.5 
—,0132 
,0126 
52 
— ,0161 
,0132 
61 
,02 75 
,0286 
,02 67 
59 
,0291 
,0299 
67 
,0425 
,0444 
,0407 
66 
,0420 
,0446 
73 
,0 575 
,0512 
,0348 
73 
,0387 
,0393 
79 
,0725 
,0688 
,0688 
1 80 
,0741 
,0740 
Factors for the correction of the Refraction, equated from the 
mean of the above, according to the proposed formula. 
Table II. 
28 
32 
36 
40 
44 
48 
49 
52 
56 
60 
64 
68 
72 
76 
80 
+,0504 
,0408 
,0312 
,0216 
,0120 
,0024 
,0000 
— ,00 69 
,0161 
,0253 
,0345 
>°437 
>0529 
,0621 
,0713 
Table III. 
20 
+ ,0325 
25 
,0420 
3 ° 
,0315 
35 
,0210 
4 ° 
,0105 
45 
,0000 
5 ° 
—,0103 
55 
,0210 
60 
,0315 
63 
,0420 
7 o 
,0323 
75 
,0630 
80 
,0 735 
85 
,0840 
