88 



Ocean Magnetic Observations, 1905-16 



The values of x, y, z, x', y', z', x", x'", and the parameters c, f, g, h, P, and Q, for the 

 period of time covered by each group-adjustment, are given in Table 31. 



The computation of inclination-deviations is shown in Table 38, page 92. 



Horizontal Intensity. — The least-square adjustment of the coeflBcients and the compu- 

 tations of the coefficients and deviations are more conveniently made if the unit of H is so 

 taken as to avoid many decimals. This is accomphshed by expressing H in units of the 



fourth decimal place c. g. s. If also x' = —k-, and x" = —7^, (19) to (23) become 



^, •10* = £r-10^-(X-l) 



B, • 10" = cH-W tan I + P-10' 



C- 10^= -/•i/-lCr'-tan7-Q-10* 



, and x" = 



2 



W 



10*= - H-W- 



The numerical values of B^ and C^, expressed in units of the fourth decimal place c. g. s., 

 may readily be computed from the values given for the period of time covered by each 

 group-adjustment in Tables 32 to 34, which give the deviation-constants and parameters for 

 the positions of sea deflector and of sea dip-circle. For the position of sea dip-circle there 

 are two sets of values: one is derived from observations of the horizontal intensity by 

 deflections, and the other is derived from the loaded-needle observations. The parameters 

 X, a, b, c, d, e, f, P, and Q are given in Table 32 for the sea-deflector position. For the dip- 

 circle position, values of the parameters already appear in Table 31, which were deduced 

 from the inclination observations. Tables 33 and 34 contain additional values for the 

 same parameters, except g and h, as also for X, a, e, and k. 



Table 32. — Horizontal-Intensity Deviation-Constants and Parameters for Sea-Deflector Position. 



Cruise 



I 

 II 



III 



Group 



Aa 



+.04 



-.00225 



-.00308 

 -.00271 

 -.00322 



-.00150 

 -.00139 

 -.00078 

 + .00094 

 + .00279 

 + .00450 



+ .00108 



+ .00086 

 + .00160 

 + .00134 



+ .00066 

 + .00039 

 + .00122 

 + .00064 

 + .00088 

 + .00102 



1.00318 



0.99754 





0.99897 



+ .00093 



-.00554 

 -.00517 

 -.00568 



-.00253 

 -.00242 

 -.00181 

 -.00009 

 + .00176 

 + .00347 



-.00006 

 + .00018 

 + .00032 



+ .00606 



+ .00361 

 + .00070 

 + .01069 



+ .00138 

 + .00103 

 + .00499 

 + .00294 

 + .00147 

 + .00043 



+ .00134 

 + .00158 

 + .00172 



+ .005431 -.00137 



c. g. 8 

 + .0015 



+ . 00062' - . 00227 + . 0010 

 + .00025 +.00036 +.0012 

 + . 00076, + . 00404 - . 0027 



+ . 00047] - . 00020 +. 0009 

 + . 00036, - . 00019 + . 0007 



-.00025! -.00021 

 -.00197J + . 00011 

 -.00.382 +.00139 

 -.00553 -.00017 



-.0006 

 + .0003 

 -.0009 

 -.0004 



c. g. a. 

 -.0001 



+ .0007 

 -.0002 

 -.0014 



.0000 

 -.0001 

 -.0005 

 -.0006 

 + .0001 

 -.0004 



Table 33. — Horizontal-Intensity Deviation-Constants and Parameters for Sea-Dip-Circk Position {Loaded-Dip Observations) 



'The deviation-corrections were not computed from these parameters, but were taken from a deviation-table 

 basad on the analysis of each swing. 



