144 
MAGNETIC OBSERVATIONS, 
OBSERVATIONS—Continued. 
Station, Camp 130, Rio Colorado ; latitude 34° 36' 19". 20 ; longitude *111. 37 m. 4.36s. 
Needle, B. Dale, February 23, 1854. Hour of beginning, 3h. 50 m. p. m.; hour of ending, 4 h. 20 m. p. m. 
Observer, Lieut. J. C. Ives, Topographical Engineers. 
o ' " 
r 60 10 
Needle vertical, face of circle north, reading of azimuth circle..J 60 08 
( 60 05 
( 60 10 
Needle vertical, face of circle south, reading of azimuth circle_ 1 60 10 
l 60 11 
Reading of azimuth circle when plane of instrument is in the magnetic meridian. 60 09 00 
Reading of azimuth circle when plane of instrument is in the true meridian____ 74 00 21 
Approximate magnetic declination...... 13 51 21 E. 
OBSERVATIONS FOR MAGNETIC INCLINATION AND INTENSITY—No. 4. 
Face of circle. 
Direct. 
Def. with wt. 2J gr. 
Def. towards 
the vertical. 
( 1 ) 
Def. from 
the vertical. 
( 2 ) 
Tlier. 
Fah. 
Def. with wt. 3 gr. 
Def. towards 
the vertical. 
( 1 ) 
Def. from 
the vertical. 
( 2 ) 
Ther. 
Fah. 
East. 
West... 
Means . 
Cor. for index error of needle. 
Deduced inclination . 
Differences 
Half diff. or angles of deflection. 
Sum of means 
Half sum — dip 
o ' 
60 20 
60 20 
60 22 
60 18 
60 25 
60 20 
o ' 
94 25 
94 20 
94 25 
94 30 
94 25 
94 20 
o ' 
26 15 
26 22 
26 20 
26 15 
26 20 
26 15 
o 
76 
76 
o ' 
102 33 
102 25 
102 30 
102 25 
102 35 
102 25 
o ' 
17 50 
17 55 
17 50 
17 40 
17 45 
17 50 
60 20 50 
(1) 94 24 10 
(2) 26 17 50 
o 
76 
( 2 ) 
17 48 20 
+ 8 48 
60 29 38 
68 06 20 
84 40 30 
34 03 10 
42 20 15 
120 42 00 
120 17 10 
60 21 00 
60 08 35 
o 
76 
76 
o 
78 
