SCALES 

 2:1 3:1 



I Divisipii = 4'Miles. 

 I Division =2 Knots 



SCALES 

 4:1 5:1 



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 con's (porpaij&f 50) 



« UibiANtt. in yarns 

 t j - . | . -j Relativa or scclz\ 



•■3 £ 8 DISTANCE in .Tales 



i I . I i I i I i 1 i I i ' 1 1 1 



WeUntfen, D.C., published Msy. 1920, £t W/drcgrafhic orncc, 

 /jnda thi Mlnorrfcj ot jrn ^SECRgTAKY OF Tr 



FIGURS 30. 



SFEID in I'.nc'-s 

 Relative or :cip::I 



Hot Put»c»tte<».Ei).,^r„ 1930 «8l.E'liiio=,/iprai 



No, 2G85« 



59 



