Figure 12.10 is the manual adjustment chart corresponding to Figure 12.3. Note that there is now a second scale, called the adjustment scale, on the vertical axis. Note also that the divisions on the adjustment scale are arranged so that one unit of adjustment exactly equals six units on the molecular weight scale. Furthermore, the units on the adjustment scale that correspond to molecular weight values above the target of 2,000 are negative, whereas the units on the adjustment scale that correspond to molecular weight values below the target of 2,000 are positive. The reason for this is that the specific adjustment equation that is used for the molecular weight variable is