38 
RECONNAISSANCE FROM CARROLL, MONTANA, 
ASTRONOMICAL OBSERVATIONS FOR TIME AND LATITUDE AT CARROLL, CAMP 
LEWIS, AND CAMP BAKER. 
Observation for time. 
Station, Carroll, Montana.—Date, July 12, 1875.—Object observed, Arcturus.—Sextant, Spencer Browning, 6536.—Chronometer, Bond & Son, 
Double altitudes observed. 
° , u 
74 50 00 
73 50 00 
74 20 00 
202.—Index error, —60/’.—Observer, Wood.—Computer, Wood. 
Corresponding times. 
Latitude = L 
N. polar dist. = A 
WAL Al 
I 
hom 8 True altitude = A 
18 54 25. 
54 (55.5 Qm=L+A+A 
55 26.5 
55 57. ™m 
56 26.5 m—A 
56 58.5 
18 57 29. log cos m 
—— log sin (m—A) 
18 55 56.9 
log cos m sin (m—A) 
log cos L sin A 
log sin? 3p 
log sin 4p 
ap 
p in are 
p in time 
KAR 
Equation of time 
True time 
Time by chron. 
Chron. fast 
Wl Wl 
Wl 
WM WM th 
° t aw 
47 35 00 
70 10 00 
37 08 20 
154 53 20 
77 26 40 
40 18 20 
9. 3372319 
9. 8108128 
19, 1480447 
9. 8024365 
19. 3456082 
9. 6728041 
sou 
05 02 
10 04 
m. 
3 44 
14 09 
8. 
40. 27 
59.5 
17 54 39.77 
18 55 56.87 
1 01 17.1 
Refraction = R 
Parallax = P 
Semi-diam. = Sd 
R, P,and Sd 
Observed 2 alt. 
HA 
Index error 
2 alt. corrected 
Altitude 
R, P, and Sd 
True alt. =A 
Hl 
log cos L 
log sin 4 
I} Il 
log cos L sin A 
fe} , “ 
74 19 00 
37 09 30 
—1 10 
37 08 20 
9, 8289930 
9, 9734435 
9, 8024365 
Determination of the latitude by observed double altitudes of Polaris off the meridian. 
Station, Carroll, Montana,—Date, July 12, 1875.—Sextant, Spencer Browning.—Index error, — 60/.—Chronometer, Bond & Son, 202.—Observer, 
‘Wood.—Computer, Wood. 
Observed double altitudes. 
° ‘ “uw 
94 33 29 
1 00 
94 32 29 
47 16 14.5 
50. 0 
AT 15 24.5 
Corresponding times. 
hom 8. log cos p = 9. 3515862 
19 19 43. log A = 3. 6897527 
20 36. —_— 
21 20. log A cos p = 3. 0413389 
22 07. = 1099.9 
22 42.5 
23° 45.5 ct ue 
19 24 45.5 1st term = 18 19.9 
—_ ——. Alt=A = 47 15 24.5 
19 22 08.5 —- 
2d term = 47 33 44.4 
Latitude = 59.7 
47 34 44.1 
MR POlATIS s2ciueremasseancowe seewad saseeeeh Lawenecess Soacecscccaenes 
Sid. time at mean 
Sid. interval from mean time of culmination 
Retardation of mean on sidereal time... 
Mean time of culmination of star...- 
noon at this station... 
Error of chron. at time of observation. 
Time by chron. of culmination .......-...-..... Susetienesseces esas 
Sid. time of observation 
Hour-angle, p, in mean time 
Sidereal equivalents in arc 
log sin p 9, 98875 
log A 3. 68975 
log Asin p 3. 67850 
log (A sin p)? 7.35700 
log a 4, 38454 
log tan A 0. 03425 
log 2d term 1 T19 
2d term 59.7 
— 50” 
1» 01m 174.1 
88° 38! 25” 
4895" 
hom & 
1 12 47.7 
1 01 171 
"2 14 048 
19 22 085 
6 51 56.3 
102° 59/ 05” 
