In an earlier paper this author suggested a method by which it appeared possible to calculate the through-put of a new distillery for essential oils during the planning phase if two relevant parameters were known. It was proposed that the oil from a single gland of an herb would form a circular surface patch when the gland bursts on contact with the steam in the distillery. This patch would have a basic area (a) and distillation would reduce its radius to nil at a rate proportional to the actual speed of the passing steam in the basic time (t) minutes, designated parameter (t).
During the initial heating period at any level of the plant charge, this basic area may be increased by an amount (da) by oil from each lower layer of herb having unit thickness. Steam of similar actual speed will then reduce the surface oil areas at the top of a lavender charge having height (H), for (a + H.da) to nil in (T) minutes, and this is the extraction time for the charge.