The present invention provides a method and apparatus configured to provide graphical symbols indicative of a separation value between a first and second location, measured from a predetermined reference point. A second or inboard dial may be located over the liquid crystal display. The reagents used for transferal of the groups are described by Formulae A-D: wherein: X=F, Cl, Br, I, sulfonate esters, phosphate esters or another leaving group; R11=tetrafluoroborates, inflates, halogen, perchlorate, sulfates, phosphates or carbonates The other variables are as defined in the claims.