TABLES. 
253 
TABLE IX. 
Distance of the Sea Horizon uncorrected for effects of Kefraction.* 
Height. 
Dis¬ 
tance. 
Height. 
Dis¬ 
tance. 
Height. 
Dis¬ 
tance. 
Height. 
Dis¬ 
tance. 
Height. 
Dis¬ 
tance. 
Height. 
Dis¬ 
tance. 
Feet. 
i*i 
Miles. 
X 
Feet. 
390 
Miles. 
21 
Feet. 
1487 
Miles. 
4 1 
Feet. 
329? 
Miles. 
61 
Feet. 
9032 
Miles. 
101 
Feet. 
17608 
Miles. 
141 
3*5 
2 
428 
22 
1561 
42 
3513 
6 3 
9393 
103 
18111 
143 
8*o 
3 
468 
23 
1636 
43 
3740 
65 
9760 
105 
18622 
M 5 
14*2 
4 
510 
24 
1713 
44 
3974 
67 
10135 
107 
19140 
147 
22*1 
5 
55 0 
25 
1792 
45 
4213 
69 
10518 
109 
19664 
149 
3 i *9 
6 
598 
26 
1872 
46 
4461 
71 
10908 
hi 
20197 
151 
43*3 
7 
645 
27 
1954 
47 
4716 
73 
11304 
113 
20736 
153 
56*6 
8 
694 
28 
2019 
48 
4976 
75 
11709 
H 5 
21282 
155 
7 i *7 
9 
744 
29 
2124 
49 
5249 
77 
12120 
117 
21836 
157 
88-5 
10 
797 
30 
2212 
5 o 
5524 
79 
12538 
IT 9 
22397 
159 
i °7 
11 
850 
31 
2 J 0 I 
5 i 
5808 
81 
12966 
121 
22964 
161 
127 
12 
906 
32 
2393 
52 
6098 
83 
13397 
123 
23540 
163 
149 
13 
964 
33 
2485 
53 
6394 
85 
13836 
125 
24121 
165 
H 3 
14 
1023 
34 
2581 
54 
6700 
87. 
14282 
127 
24711 
167 
199 
15 
1084 
35 
2677 
55 
7012 
89 
14737 
129 
25307 
169 
226 
16 
1147 
36 
2775 
56 
7332 
9 i 
15197 
131 
25911 
171 
256 
17 
1211 
37 
2875 
57 
7656 
93 
15664 
133 
26521 
173 
287 
18 
1278 
38 
2977 
58 
7987 
95 
16139 
135 
27139 
175 
319 
19 
1346 
39 
3081 
59 
8330 
97 
16622 
137 
27764 
177 
354 
20 
1416 
40 
3186 
60 
8678 
99 
17111 
139 
28396 
179 
{Approximately the distance visible in miles is the square root of the height in feet, an acci¬ 
dental relation easy to remember.) 
* The effects of refraction at low angles are very variable, but in ordinary cases, if the height 
of observer be supposed to be increased by one-third, the distance of the visible sea horizon will 
not exceed the tabular value corresponding to the revised entry. Extraordinary cases are those of 
mirage, &c., for which no general rule can be given. 
