MAGNETIC OBSERVATIONS. 
115 
OBSERVATIONS—Continued. 
Station, Camp 81, Colorado Chiquito ; latitude 35° 01' 21''. 03; longitude Hi. 21m. 58. 81 s. 
Needle, B. Date, December 8, 1853. Hour of beginning, 1 k. 15m. p. m.; hour of ending, 1 h. 40 in. p. m. 
• Observer, Lieut. J. C. Ives, Topographical Engineers. 
o / V 
1 40 43 
Needle vertical, face of circle north, reading of azimuth circle. ) 40 38 
( 40 30 
1 40 53 
Needle vertical, face of circle south, reading of azimuth circle.■/ 40 43 
( 40 46 
Reading of azimuth circle when plane of instrument is in the magnetic meridian.... 40 42 10 
Reading of azimuth circle when plane of instrument is in the time meridian.. 54 03 01 
Approximate magnetic declination ........._ 13 20 51 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) 
Ther. 
Fall. 
Def. with wt. 2J gr. 
Def. towards 
the vertical. 
( 1 ) 
Def. from the 
vertical. 
(2) 
Ther. 
Fah. 
East. 
West. 
61 35 
61 33 
61 30 
61 33 
61 30 
61 30 
o ' 
87 45 
87 37 
87 35 
87 36 
87 40 
87 32 
o < 
35 27 
35 30 
35 25 
35 20 
35 18 
35 20 
o 
55 
55 
94 40 
94 50 
94 43 
94 40 
94 45 
94 37 
28 10 
28 12 
28 10 
28 12 
28 05 
28 07 
Means. 
61 31 50 
j (1) 87 37 30 ) 
| (2) 35 23 20 j 
o 
55 
j (1) 94 42 30 ) 
j (2) 28 09 20 j 
Corr. for index error of needle.. 
-}“ 8 48 
Deduced inclination 
61 40 38 
Differences. 
52 14 10 
Half diff. or angles of deflection. 
26 07 05 
Sum of means. 
Half sum — dip . 
123 00 50 
61 30 25 
o ' " 
66 33 10 
o ' n 
33 16 35 
o ' » 
122 51 50 
61 25 55 
o 
55 
