76 | MAGNETIC OBSERVATIONS. 
OBSERVATIONS WITH FOX'S MAGNETIC INCLINATION AND INTENSITY INSTRUMENT. 
Station, Cambridge Observatory ; latitude 420 22 48" ; longitude 4h. 44m. 29. 6s. 
Needle, C. Date, August 9, 1850. Hour of beginning, 11h. a. m.; hour of ending, 11۸ 15m. a. m. 
Observers, Prof. W. C. Bond and Lieut. A. W. Whipple. 
O r r 
> : 47 49 
Needle vertical, face of circle north, reading of azimuth circle 47 47 
47 47 
47 26 
Needle vertical, face of circle south, reading of azimuth circle tt 2 
4 0 
Reading of azimuth circle when plane of instrument is in the magnetic meridian.----------------- 47 49 00 
Reading of azimuth circle when plane of instrument is in the true meridian 4 38 18 45 
Approximate magnetic declination ... 9 30 15 W. 
OBSERVATIONS FOR MAGNETIC INCLINATION—No. 1. 
With marked end of needle, N. With marked end of needle, S. 
pole. 
š Therm Thermom. 
— Fahrenh' t. Fahrenh't. 
North end of | South end of North end of | South end of 
. needle reads— | needle reads— needle reads— | needle reads— 
° , ” [o] , Hi [e] 0 , " [o] H " O 
74 40 T4 55 75 74 28 74 23 75 
East 74 30 IK A A A کی‎ 74 38 TE 45 °` PRA 
74 28 ٠ ة2 پل و‎ 74 40 re 435.7 dux 
TE M JE 297 7 Lor بی اک‎ 74 82 Pe "250 Se nes 
West 7 18 39. d. EE 74 30 4480. NS 
14 33 TE ME SL OP "4 30 74: 90 . _ موب ممیت[‎ 
Means 74 32 30 74 84 20 75 74 33 00 74 35 30 15 
67 Mean of four results. 140. 33. 507 
Station, Cambridge Observatory ; latitude 420 22' 48" ; longitude 4h. 44m. 29. 6s. 
Date, August 9, 1850. Hour of beginning, 10h. 25m. a. m. ; hour of ending, 10h. 45m. a. m. 
SC Les i 
85 10 1 
E Face west...... 1 85 14 1 
Reading of azimuth circle when plane of instrument is in the true meridian...... 85 10 1 
¡ Face east. ..... | 
L 85 15 
C RR EM. d 
Mean 85 12 15 | 
Needle (C) vertical, face of circle north, reading of azimuth circle by a mean of five observations--- - 93 53 12 | 
Needle (C) vertical, face of circle south， "reading of azimuth circle këng a mean of five observations.....- 95 31 48, í 
Reading of azimuth circle when plane of instrument is in the idi : 94 42 30 à 
Reading of azimuth circle when plane of instrument in the true meridian 85 12 15 | 
Approximate magnetic declination ------ s ۱ 9 30 15 W. 
