212 



REPORT ON 



Iu the same way, the first equation of condition for the After Binnacle Compass is 

 = 220 + A, -r 0. 195 B, + 0.981 C, + 0.383 A + 0.924 E,. 



EQUATIONS OF CONDITION AT CEARA. 



From these equations of condition five normal equations were obtained for each 

 compass by the method of least squares; but on attempting to solve them the 

 numerical coefficients of Z>, and E r came out so small that no confidence could be 

 placed in the resulting values of these quantities ; and moreover, the uncertainty of 

 them vitiated the values of A^ B^ and (7,. It was therefore considered best to 

 reject the normal equations in Z>j and J?j, and to employ in their stead the equations 



using for ) and Q the numerical values already found. The following are the 

 normal equations thus formed, and the resulting values of A^ -B,, (7, Z>,, and E t , for 

 each compass. For convenience of computation, the unit of the absolute terms of 

 the normal equations has been changed from minutes of arc to radius. 



ADMIRALTY STANDARD COMPASS. 



Hence 



0.0043 = o 14.8 



