reckoned point of arrival and from it the dead reckoned distance R 

 and the angle 9. From figure 12 : 



Mjt /L = sin e = Ct IR or R = LCt jMjt 

 also (Mc^+i?)/L = cos 



whence iMct-\-R)- = L^-MjT~ 



substituting the \'alue of R and rearranging: 



CL = Mj iVL'-MjH-'-Mct) 



Figure 12. — Derivation of CL in terms of measured components. 



This expression is general if the convention is adopted that M,. is 

 positive if directed with the ship's heading and negative if counter 

 to the ship's heading. 



In earlier comparisons only general agreement had been ob- 

 tained between currents derived from GEK measurements and 

 density distribution. In addition to the possibility that one or 

 more of the various assumptions made might be significantly 

 erroneous, it was recognized that in contrast with the average 



204964—53—6 



33 



