An extreme generalization ("point octopole ") would be: Eight alternating point charges at the eight corners of a parallelepiped, e.g., of a cube with edge length a. The "octopole moment" of this arrangement would correspond, in the "octopole limit" lim a → → 0 a 3 ⋅ ⋅ Q → → const. to a nonzero diagonal tensor of order three. Still higher multipoles, e.g. of order 2 ℓ ℓ , would be obtained by dipolar (quadrupolar, octopolar,...) arrangements of point dipoles (quadrupoles, octopoles,...), not point monopoles, of lower order, e.g., 2 ℓ ℓ − − 1 .