MAGNETIC OBSERVATIONS. e 121 
OBSERVATIONS Continued. 
Station, Camp 86, Colorado Chiquito; latitude 35° 20’ 54".12 ; longitude Th. 23m. 45.308. 
Needle, B. Date, December 18, 1853. Hour of beginning, 3h. 20m. p. m. ; hour of ending, 3h. 50m. p. m. 
Observer, Lieut. J. C. Ives, Topographical Engineers. 
0۰ r ” 
39 12 
Needle vertical, face of circle north, reading of azimuth circle 39 12 
3 89 12 
1 i 39 18 
| Needle vertical, face of circle south, reading of azimuth circle 89 11 
| 89 15 
Reading of azimuth circle when plane of instrument is in the magnetic meridian.................. 89 13 20 
Reading of azimuth circle when plane of instrument is in the true meridian 
| Approximate magnetic declination 
l 
| OBSERVATIONS FOR MAGNETIC INCLINATION AND INTENSITY—No. 4. 
| Def. with wt. 2 gr. Def. with wt. 23 gr. Def. with wt. 3 gr. 
Face of circle. Direct. 
; Def. towards | Def. from the | Ther. | Def. towards | Def. from the | Def. towards | Def. from 
the vertical.| vertical. Fah. | the vertical. | vertical. the vertical. | the vertical. 
1 (2) ۱ 1 (2) (1) (2) 
Oo at 56 a e^ 2 ° Ee e et , ë م‎ 
í 61 58 87 43 85 45 40 94. 35 28 45 102 33 20 48 
East 61 52 87 45 So. 9 سر ا ما‎ 94 20 28 48 102 28 20 55 
۱ 61 60 87 45 25 OR. 1...a9. 94 30 28 45 102 27 20 58 
61 59 87 38 ab. 00" Te 04 28 28 40 102 28 20 48 
West-......... 61 50 87 30 E ae 94 32 28 38 102 18 20 38 
61 48 87 40 35 45 40 94 30 28 45 | 102 20 20 35 
| 
° , ” 0 D "m [e] , ” [0] , " 
سو‎ (1) 87 40 10 (1) 94 29 10 (1) 102 25 40 } 
mower ory ae E 61 54 30 i (2) 35 49 10 40 (2) 28 43 80 (2) 20 47 00 
Cor. for index er- TTE 
ror of needle...| 十 8 48 
Deduced inclina- | © 2 
tion 62 03 18 
o , "n Oy D " o , ep 
Differences br Sl Oe LC 65 45 40 81 38. 40 
Half diff. or angles [e] H " ° , , , ” 
of deflection S58 BB 4305 Lol. 32.62 0 40 49 20 
o , " o , " [e] ۳ " 
Sum of means 129 29 وو‎ (3:1 Mg... 123 12 40 123 12 40 
d o ۳ de o r " o ۳ a 
Half sum 一 dip DE. 44° ماک‎ o... Gi 36 20 i 61 36 20 
