Reports of explorations and surveys, to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean: Vol. 2, Pt. 4

APPENDIX L.-ASTRONOMICAL OBSERVATIONS.
ASTRONOMICAL OBSERVATIONS-Continued.
Determnzination of longitude by lunar distances.-The Moon's west erny limb and Pollux, west.
Altitude. Magnetic bearing.
d. m. s. d. mn. s.
74 59 30 S. 49 00 00 E.
Time.
A. m. s.
7 00 31
7 O3 19
7 05 18
7 07 03
Variation of compass, E. 100 19' 12". Thermometer 66~ Fah.
Double altitude of the Moon's upper limb, in the east.
Time. Altitude.
h. m. s. d. m. s.
7 08 49 69 20 55
DETERMINATION OF LONGITUDE nBY LUNAR DISTANCES.
Approximate latitude to be used in first computation of time,
33~ 45'.
Determination of time, May 10, 1854.-Double altitudes of Pol lux, in the west.
Time. Altitudes. Chronometer slow o
mean time.
h. m. M. d s.h. m.s.
6 38 24 94 44 25 1 3 15.4
6 39 33 94 1705 1 3 12.3
6 40 22 93 56 55 1 3 12.4
6 41 18 93 34 15 1 3 16.5
6 42 13 93 10 05 1 3 14.5
6 43 05 92 48 25 1 3 13.5
6 43 57 92 27 45 ] 3 12.0
6 44 55 92 03 05 1 3 13.8
6 45 40 91 44 15 1 3 13.0
6 46 33 91 22 55
Double altitudes of Areturus, in the east.
Time. Altitudes. Chronometer slow of
mean time.
h. m. s. d.. s. h. m. s.
6 48 23 94 32 45 1 3 14. 3
6 49 22 94 57 05 1 3 13.8
6 50 27 95 25 55 1 3 16.4
6 51 13 95 4305 1 3 14.6
6 51 57 96 01 05 1 3 13.8
6 52 53 96 24 35 1 3 14.6
6 53 47 96 47 35 1 3 16.4
6 54 34 97 0605 1 3 14. 4
6 55 17 97 24 25 1 3 15.6
6 56 13 97 4705 1 3 14.6
Time. Altitude.
h. m. s. d. M. s.
7 11 30 81 08 15
h. M59.
7 13
7 15
7 16
7 18
7 18 59 98 15 OS 6 29 OS
Time. Altitude.
h. m. s. d. Mn. s.
7 23 38 73 27 35
Thermometer 56~ Fahrenheit.
I
154
Double altitude of qpica Vi?-,,,inis, in the cast.
Tiine.
A. M. S.
7 21 03
Deduced longitude.
h. M..3.
Angular distaneeig.
d. m. s.
98 06 15
98 07 35
8 ('8 3 I'j
98 09 25
6 29 07
ON ELM FORK OF TRINITY RIVER.
Double altitude of Pollux, in the we-st.
Time.
Angular.distances.
Ded,uced loi3gitude.
h. M. S.
c7,.
98
98
98
98
S.
17
00
55
59
M.
I I
l
14
15
S.
45
55
05
05
6 29 08
.Double altitude of Pollux, in the west.
Time. Altitude.
h. M. S. d. M. S.
7 22 07 76 46 55
Double altitude of the JI-oon's upper linib, in the east.