MAGNETIC OBSERVATIONS, 
OBSERVATIONS—Continued. 
115 
Station, Camp 132, liio Colorado; latitude 34° 45' 53". 60 ; longitude 7 h. 37 m. 31. 23s. 
Needle, B. Date, February 25, 1854. Hour of beginning , 2 h. 50m. p. m.; hour of ending, 3h. 10 m.p. m. 
Observer, l.icut J. C. Ives, Topographical Engineers. 
O ' " 
f 19 30 
Needle vertical, face of circle north, reading of azimuth circle____19 28 
( 19 20 
1 19 20 
Needle vertical, face of circle south, reading of azimuth circle___-! 19 30 
l 19 30 
Reading of azimuth circle when plane of instrument is in the magnetic meridian_ 19 28 00 
Reading of azimuth circle when plane of instrument is in the true meridian___ 33 03 41 
Approximate magnetic declination. 13 35 41 E. 
OBSERVATIONS FOR MAGNETIC INCLINATION AND INTENSITY—No. 4. 
Face of circle. 
Direct. 
Def. with wt. 2\ gr. 
Def. towards 
the vertical. 
(1) 
Def. from 
"the vertical. 
( 2 ) 
Tlier. 
Fah. 
Def. with wt. 3 gr. 
Def. towards Def. from 
the vertical, the vertical. 
(1) I (2) 
Ther. 
Fah. 
East. 
West. 
o ' 
60 40 
60 38 
60 42 
60 37 
60 37 
60 40 
Means. 
60 39 00 
Cor. for index error of needle.. 
Deduced inclination. 
i a 
+ 8 48 
60 47 48 
Differences. 
Half diff. or angles of deflection 
Sum of means. 
Half sum = dip , 
o ' 
94 35 
94 30 
94 40 
94 30 
94 40 
94 38 
o ' 
26 25 
26 30 
26 30 
26 20 
26 15 
26 18 
(1) 94 35 30 
(2) 26 23 00 
68 12 30 
o 
34 
06 15 
120 58 30 
o 
60 
29 15 
o 
76 
76 
76 
o ' 
102 45 
102 43 
102 40 
102 35 
102 40 
102 30 
o ' 
18 22 
18 25 
18 28 
18 20 
18 20 
18 17 
(1) 102 38 50 
(2) 18 22 00 
84 16 50 
42 08 25 
121 00 50 
60 
30 25 
o 
76 
76 
o 
76 
19 m 
