This section is from the book "An Experimental History Of The Materia Medica", by William Lewis.
Foeniculum; Marathrum. Fennel: an umbelliferous plant, with dark green leaves divided into long capillary segments: the umbels are somewhat concave, and have no leaves or cup at their origin: the seeds oval, oblong, marked with prominent striae: the root straight, white, about the thickness of the finger.
I. Foeniculum dulce Pharm. Lond. & Edinb, & C. B. Anethum Faenculum Linn. Sweet fennel: with whitish or pale greenish yellow seeds, generally crooked. It is annual, a native of the warmer climates, and cultivated in our gardens. The shops are commonly sup-plied, from Germany, with seeds, superiour to those of our own growth.
Sweet fennel seeds are an useful stomachic and carminative; of an agreeable aromatic smell, and a moderately warm sweetish taste. They are sometimes given in powder, from a scruplc to a dram; and sometimes candied.
Water extracts the virtue of these seeds very imperfectly by infusion, but carries it off totally in evaporation: after repeated infusion, they retain part of their aromatic warmth, and the liquors are much less agreeable than the seeds in substance; after boiling for some time, the seeds prove entirely insipid, and the decoction, infpif-fated to the consistence of an extract, is very nearly so. By distillation, they impregnate water with their flavour: a gallon receives a strong impregnation from a pound of the seeds. A large proportion of essential oil separates in the distillation, and floats on the surface of the aqueous fluid: in colour yellowish, in smell moderately strong and diffusive, and exactly resem-bling the fennel, in taste mild and sweetish like the oil of aniseeds, and like it also congealing, by a slight cold, into a white butyraceous mass.
These seeds contain likewise a considerable quantity of a gross oil of the expressed kind, which, when freed from the essential oil, discovers no particular smell or taste. This oil is extracted, along with the aromatic matter of the fennel, by digestion in rectisied spirit, but sepa-rates and rises to the surface upon inspiffating the filtered tincture. The spirit, gently distilled off, has very little of the flavour of the seeds; the oily matter retains a part both of their taste and smell; but much the greatest part remains concentrated in the extract.
Aqua foeni-culi Ph. Lond.
2. Foeniculum vulgare Pharm. Edinb* Foeniculum vulgare germanicum C. B. Common fennel or sinckle: with smaller, dark coloured almost blackish seeds. It is now reckoned only a variety of the former.
The seeds of this kind are warmer and more pungent, but less sweet, and of a less grateful flavour, than those of the preceding; and the same difference obtains in the distilled waters, distilled oils, and the spirituous extracts of the two kinds. The spirituous tinctures are some-what different also, as the seeds themselves, in colour: those of the sweet fennel seeds being yellowish, of the common greenish.
The leaves of common fennel have the same kind of flavour with the seeds, and are in smell stronger, though in taste weaker and less agreeable. They impregnate water, by distillation, with a sufficiently grateful flavour, and yield a considerable portion of essential oil. An extract made from them by rectified spirit is likewise no inelegant aromatic: the colour of the spirituous tincture is a deep green.
The roots, taken up early in the spring, have a pleasant sweetish taste, with a slight aromatic warmth; but nothing of the peculiar strong flavour of the leaves and seeds. They are ranked among the aperient roots, and supposed by some to be equivalent in virtue to the celebrated ginseng of the Chinese, from which however they differ considerably in their sensible qualities (fee Ginfeng). They give out their virtue, by infusion or slight coction to water, and by moderate digestion to rectisied spirit: to the latter they communicate a pale amber colour, to the former a wheyish appearance. The aqueous infusions are in taste considerably the strongest, but on being infpiffated, they yield an extract of very little taste and in very small quantity; greatest part of the sweetish matter as well as the aromatic being dissipated in the evaporation. The spirituous extract is in larger quantity, about one twelfth the weight of the root, and of a moderately strong taste; agreeable, unctuous, sweetifh, lightly aromatic, with some small admixture of bitterishness.