146 MAGNETIC OBSERVATIONS. 
OBSERV ATIONS— Continued. 
Station, Camp 135, Rio Colorado ; latitude 340 52' 15".60; longitude Th. 38m. 06.885. 
Veedle, B. Date, March 1, 1854. Hour of beginning, 4h. 40m. p. m. ; hour of ending, 5h. 05m. p. m. 
Observer, Lieut. J. C. Ives, Topographical Engineers. 
° 1 
83 25 | 
Needle vertical, face of circle north, reading.of azimuth circle 1 i 83 30 
83 20 
83 25 
Needle vertical, face of circle south, reading of azimuth circle 83 15 
83 22 
Reading of azimuth circle when plane of instrument is in the magnetic meridian - 83 22 50 
Readiug of azimuth circle when plane of instrument is in the true meridian 97 18 43 
Approximate magnetic declination 13 55 53 卫 . 
OBSERVATIONS FOR MAGNETIC INCLINATION AND INTENSITY—No. 4. 
| Def. with wt. 23 gr. Def. with wt. 3 gr. 
Face of circle. | Direct. | 
| Def. towards| Def. from Ther. | Def. towards, Def. from Ther. 
| the vertical. | the vertical. | Fah. | the vertical. the vertical. | Fah. 
(1) | 
0 , o , ° , ° ° , do? o 
60 46 94 35 26 40 61 102 32 18 20 61 
East 60 50 94 35 7 E Tupay ses 102 40 18 25  |...----- 
60 50 94 25 256 4D > Losas 102 30 18 22  |...-.--* 
H 60 50 94 40 28 00 میت‎ 102 32 18 28 |-------- 
West 60 4T 94 30 36 4T. d. oce 102 40 18 22  |-------- 
l 48 94 30 26 50 57 102 37 18 37 57 | 
Qo *-- 0 ” [e] o H " 
M (1) 94 32 30 DN M 983131. کا‎ 
TM 0 1 (2) 26 4T 00 = (2) 18 27 20 
= | 
Cor. for index error of needle...| + 8 48 
G F 7P 
Deduced inclination. ..........| 60 57 08 
O D H 1 " 
Differences..... 6۶ 45b 39 K 122205 84 07 50 — |..------ 
0 , " 7 " 
Half diff. or angles of deflection oe E — qur 42 03 55 |-------- 
0 , 11 1 il 
Sum of means Pi- OO Gans 191 02.90 — |.--.- 
[e] , " o 7 " 
Half sum — dip 6.39 77 "e 31 E ` Loose 
