colour                  Colour palette
scale_colour_soil       FAO Soil Reference Groups Colour Scheme for
                        ggplot2
scale_colour_stratigraphy
                        Geologic Timescale Colour Scheme for ggplot2
scale_colour_tol        Paul Tol's Colour Schemes for ggplot2
scale_tol_discrete      Paul Tol's discrete colour schemes for ggplot2
scale_tol_diverging     Paul Tol's diverging colour schemes for ggplot2
scale_tol_sequential    Paul Tol's sequential colour schemes for
                        ggplot2
