164 
GEOGRAPHIC TABLES AND FORMULAS. 
[bull. 214. 
Table 20. — Geodetic position computations. 
TABLE OF LOGARITHMS OF FACTORS A, B, C, D, E, F, BASED UPON THE CLARKE SPHE- 
ROID OF 1866 AND THE METRIC SYSTEM, BETWEEN LATITUDES 0° AND 72°. 
[Extracted from reports of the U. S. Coast and Geodetic Survey.] 
CONSTANTS. 
A = 
B = 
C = 
D = 
E = 
(1 — e 2 sin 2 g>Y- 
a arc l" 
( 1 — e 2 sin 2 <p) * 
a {1 — e 2 ) arcl" 
(1 — e 2 sin 2 <p) 2 tan <p 
2a 2 (1-e 2 ) arcl" 
| e 2 sin cp cos <p arc V 
1 — e 2 sin 2 <p 
(1 + 3 tan 2 <p) (l-e 2 sin 2 
<P) 
fvr 
F = T 1 3 sin q> cos 2 <p arc 2 V 
log 
a (1 — e 2 ) arc V 
log a = 6.804 698 57 
log 6 = 6.803 223 78 
log e 2 = 7.830 502 57 
= §.509 726 56 
= 8.512 676 15 
a arc 1' 
1 
l0g t ; 
1 
1.406 947 6 
2a 2 {1 — e 2 ) arcl" 
log (f e 2 arc 1") =2.692 168 7 
log ~ = 5.612 45 
log ( T V arc 2 1") = 8.291 96 
Ratio adopted in this table is the Clarke value of the meter, namely, 1 meter = 
39.370432 inches. 
