212 QUEENSLAND AGRICULTURAL JOURNAL. [1 Supr., 1898. 
From the writer’s experience, peppermint grows from 2 to 3 feet in 
height, and if well-manured will give heavy crops. Calculating proportionally 
from a small patch, a return at the rate of 9 tons to the acre has been obtained 
at one cutting, supplemented by an aftermath at the rate of 2 tons per acre, 
making in alla return at the rate of 11 tons per acre from first year’s plants. 
The season, however, was exceptionally favourable, and the ground well 
manured, Strange to say, the second cutting smelt very much stronger of 
peppermint than the first, and when handling the dried herb the menthol 
fumes were unpleasantly strong to the eyes. 
Peppermint may be planted in the spring in the same manver as ordinary 
mint, about 15 to 18 inches each way; a piece of runner about 4 inches long, if 
placed diagonally in the ground, will soon take root and spread over the 
surface, strangling the very hardiest of weeds, which seem to have no show 
amongst peppermint. One planting will generally last five years. After 
cutting, the field should be either covered with about 2 inches of soil or 
ploughed in, 
The oil is extracted in the ordinary manner of distillation by direct 
contact with fire. Most essential oils are extracted by means of steam heat, 
but it is said that peppermint needs the direct action of fire to extract some of 
the properties of the plant. The process is very simple, much more so than 
jam-making. 
The writer has seen very good peppermint oi! produced with no better 
means than a kerosene lamp, an old brass hot-water kettle, a couple of feet of 
glass tubing, a sponge, and cold water; condensation being effected by 
. occasionally squeezing cold water from the sponge on to the glass tube. 
In England 1 ewt. of peppermint is said to yield from 12 to 16 oz. of oil, 
valued at about £2 per 1b. Victorian figures differ somewhat from these, as 
growers there state that an acre yields from 8 to 5 tons of green herb, giving 
from 5 to 7 Ib. of oil per ton, valued in London at about 25s. per lb. A well- 
known Brisbane chemist distilled 5 lb. of dried herb for the writer last year, 
and obtained a return of 3-o0z. of very good oil. 
Quoting from an American paper :—“ Some 150,000 lb. of peppermint oil 
are produced annually in Michigan alone from about 15,000 acres of land. It 
takes about 350 |b. of dried herb to produce 1 Jb. of oil, an acre of land 
yielding from 6 to 10 Ib. of oil, and in exceptional cases even as great a 
quantity as 501b. The plant is cut when in blossom, like hay, and when dried 
is placed in wooden vats and steamed until the oil passes over with the vapour 
through the worm or condenser into the receiver, where it separates from the 
water and is drawn off.” 
It has been found by experiment that dried peppermint herb affords by 
distillation over a naked fire, a greater quantity of oil than by steam distillation; 
the oil obtained by the latter method being specifically lighter and of a brighter 
colour than that obtained by the former. 
Fresh herb yields equal quantities of oil by both methods. The dried 
herb contains two different oils having different boiling points and specific 
gravities, 
That well-known chemical, menthol, is a stearoptene obtained from the 
oil of Mentha piperita and other allied varieties of peppermint. 
Of all scent-yielding plants, peppermint is more likely to be successfully 
grown in Southern Queensland than any other, owing to its hardy nature, and 
the fact that it may be dried and housed like hay, and the oil extracted at the 
grower’s leisure, say during the winter months. 
Several kinds of peppermint are indigenous to Queensland. One kind 
found growing on the banks of some of the Western rivers is very strongly 
scented, and travellers have often made use of its perfume to keep flies away, 
a few leaves of the plant dropped into a pint-pot of tea acting as a most 
effective deterrent to flies with suicidal intentions. This plant may in the 
future be profitably cultivated by some of the Western settlers. 
