TABLE OF CONTENTS. 



Mode of making observations of inclination 



Mode of computing the vertical and total force 



Abstract of observations for magnetic declination, inclination, and force 



Final values of the magnetic elements at each station 



Observations of magnetic declination .... 



Observations of magnetic inclination .... 



Horizontal intensity. Observations of vibrations . 



Horizontal intensity. Observations of deflections . 



Section V. Observations on the Magnetism of the Ship. 



Description of the Monadnock ...... 



Positions of the compasses ...... 



Mode of swinging the ship ...... 



Corrections peculiar to the After Binnacle and After Ritchie Compasses 

 Officers who observed the compasses ..... 



Mode of measuring magnetic force on board ship .... 



Mathematical theory of the deviations of the compass 

 Correction of observed deviations for constant errors 



Observations for determining the deviations of the Admiralty Standard Com- 

 pass ......... 



Observations for determining the deviations of the After Binnacle Compass 

 Observations for determining the deviations of the After Ritchie Compass 

 Observations for determining the deviations of the After Azimuth Compass 

 Observations for determining the deviations of the Forward Alidade Compass 

 Observations for determining the deviations of the Forward Binnacle Compass 

 Observations for determining the deviations of the Forward Ritchie Compass 

 Mode of computing the coefficients A v B v O v D lt E x . 

 Values of these coefficients for each compass at each station 

 Probable errors of the values of the coefficients A v B v C v D v E l 



P aP f Q _, *Q 



Computation of the constants A lt , 



and 



for each 



compass . . . 



Values of the coefficients 31, S3, @, ©, (£, for each compass at each station 



Table showing the values of the constants A, =9(, ' > — > — ■— ■ — > — » 



x x x x x x 



<£), and (£, for each compass ...... 



Computation of the coefficients 21, 35, (5, £>, (£", for each compass at each 



station, from the constants A v -, — ,—,•', l , A - , £), and Q 



XX XXX X 



Comparison of the coefficients thus computed with those found directly from 



"the observations at each station .... 

 Resulting probable errors ..... 

 Does the theory accurately represent the semi-circular deviation 

 Tables showing the most important features of the deviations of each com 



pass during the cruise ..... 

 Hard and soft iron forces . 

 Magnetic moment of magnets used for measuring horizontal force 



ship 



Observations for absolute force at the Admiralty Standard Compass 

 Observations for absolute force at the After Azimuth Compass 

 Values of x 



Values of g, h, k, R and a/?, for the Admiralty Standard and After Azimutl 

 Compasses ....••• 



n board 



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