Motivated by the marked potential in reducing the macromixing time-scale by correct feed placement, the effect of using multiple such feed points was studied next. As the first-order rate constants (eq 6) of the dispersion model are inversely proportional to the vessel's working height squared, 2 , any reduction in height would greatly increase the mixing rate if the dispersion coefficient remained constant. Likewise, increasing the dispersivity would improve the rate in a given geometry. However, decreasing the height is unlikely to be a practical option and a greater dispersivity would require a higher power input for stirring. Could this square-relationship then be exploited without changing the vessel's geometry or the stirrer's power? The zero-gradient boundaries of the model (section 2.1) imply that dividing the working height into equally sized compartments with feed points in the centers will divide the axial domain length, the height , by owing to symmetry. The limiting rate constant subsequently increases in proportion to the number of feed points squared, 2 : for example two symmetrically placed feed points divide the mixing time-scale by 4 and three points by 9. Compared with a single feed at the top, four ideally placed feed points divide the time-scale in theory by 64 (4 × 4 2 ). Thus, a closer inspection of these hypothetical order-of-magnitude mixing rate gains was warranted.