e 
MAGNETIC OBSERVATIONS. 95 
£ OBSERVATIONS—Continued. 
Station, Camp 67, Agua Fria ; latitude 35° 01 35". 56 ; longitude Th. 11m. 53s. 
Needle, B. Date, November 17, 1853. Hour of beginning, 4h. 30m. p. m. ; hour of ending 10m. p.m. 
Observer, Lieut. J. C. Ives, Topographical Engineers. 
o H " 
1 { T 8 
Y Needle vertical, face of circle north,reading of azimuth circle ۲ 19 
| e 0 
Í 7 46 
Needle vertical, face of circle south, reading of azimuth circle | 7 35 
7 41 
Reading of azimuth circle when plane of instrument is in the magnetic idi 7.82. 0 
Reading of azimuth circle when plane of instrument is in the true meridian 20 57 42 
Approximate magnetic declination 13 25 32E, 
a 
OBSERVATIONS FOR MAGNETIC INCLINATION AND INTENSITY—No. 4. 
` 
Def. with wt. 2 gr. Def. with wt. 22 gr. 
Face of circle. Direct. š | 
E Def. towards | Def. from the | Ther. | Def. towards | Def. from the | Ther. 
» the vertical. vertical, Fah. the vertical. vertical, Fah. 
(1) (2) (1) (2) 
o , 0 f 0 7 [e] O H 0 , 
61 60 87 45 36 05 46 94 15 28 50 46 
East. 61 50 87 5 ENS Pere 94 20 28 4T bessen 
61 70 87 45 86. "08 — Leger 0 94 25 28 60 | nee S aae 
E 61 55 87 28 85 "507 Tum i sl 94 15 29 8ی و‎ 
West 61 57 87 30 Nm Ee | 94 20 COME TD +2 
61 45 87 25 35 58 46 | 94 18 28 48 46 
[e] , ” 1 0 , ” á ° , ” ۳ 
1) 87 34 40 (1 94 18 50 1 
Menem "n e d 2) 36 02 20 } سے‎ 1 (228 48 20 As 
x | 
* u 
| Corr. for index error of needle...| +8 48 
| * o Fo | 
Deduced inclination. ---------- 62 04 58 
o , " [e] , " 5 
| Differences TEE 1 eer ew Ww LI 
| 
ok * š o 7 " [e] , " 
Half diff. gles of deflection 25 46 B Le. 33 45 15 8 30 790 
E ud fe} r " [e] , 
rm Sum of means 123 37 00 ampara 123 07 E [.....-.. 
۱ 
o , Ki | ° , ” 
Half sum — dip 61 48 20 GS | 61 33 BE OL. 
I و‎ LI uuu 
