SCALES 

 2:1 3:1 



ii i . « i 



^ Vrp - mMi H pr^ 



Given any two corresponding quantities, solve 

 -for third by laying rule through points on prop- 

 er scales and read intersection on third scale. 



MANEUVERING BOARD 



Price 60 conls (per pad of 50) 



« a 9 *^ s ass? s s 



i i i i i i i i i i 1 1 1 1 1 1 1 ^i-^Ti , . . , i . ■ i,..,i,..,i,,,,i„,,i,,„i,,„i 



Washington, DO. puNiihed M«y. 1920. at Hydrojraphic Offic*. 



undcf the tulhwity of Ihe SECRETARY OF THE NAVY Nm MKatiOK 4th. Ed, Apr, 1938 4th. Edition, April 1938 



FIGURE 38. 



SPEED in knots 

 Relative or actual 



75 



