The Physiomedical Dispensatory by William Cook, M.D., 1869    

PTELEA TRIFOLIATA

WAFER ASH, WING SEED, SHRUBBY TREFOIL, HOP TREE

Description:  Natural Order, Rutaceae.  In the same Family with prickly ash and ailanthus.  This is a tall shrub, six to twelve feet high, with a thin, roughish, and dark gray bark. Leaves compound in threes; leaflets ovate, pointed, obscurely serrate, with pellucid dots, downy when young.   Flowers polygamous, in compound terminal cymes, small, greenish-white, three to five sepals and petals, numerous stamens, of a disagreeable odor.   Fruit a two-celled and two-seeded samara, a little larger than a flattened pea, bordered by a broad and thin wing all around, making the samara about three-fourths of an inch in diameter, and with the appearance of a large membranous-white wafer.  This fruit is a little bitterish, and was used as a substitute for hops by the early settlers.

Properties and Uses:  The bark of the root is used in medicine.   It contains a large quantity of a peculiar, pungent, and sickening oil, on which the greater portion of its action depends. It acts as a stimulant and relaxant, slowly exciting the stomach and circulation, and expending a considerable portion of its power on the lungs.  It is classed as a stimulating tonic, exerting a mild laxative influence, and employed with much praise in bilious intermittents; but it often proves very disagreeable to the stomach, and can not be used in any considerable quantities without creating a burning sensation, disgust, and a stinging erysipelatous eruption on the surface.  Within a few years past, it has been commended in the highest terms for asthma. My own experience scarcely justifies much hope from it in this direction; but it is quite stimulating to the lungs, and may be used, in combination with milder and more agreeable agents, in old and debilitated coughs.  Dose of the powder, ten to fifteen grains three times a day.  Water does not act well on it; but diluted alcohol forms a tincture of considerable power, of which a fluid drachm may be used three times a day.   Not uncommonly a portion of the oil separates and floats atop, on adding this tincture to water or sirup.   The oil (oleo-resin) is sometimes obtained by making a saturated tincture with absolute alcohol, adding this to water, and distilling on" the alcohol.  The oil remains floating on the water, from which it can easily be removed.  It has been called ptelein; and is a yellowish- brown oil,  nearly as  thick  as  molasses,  of a  very  disagreeable  odor and taste, and acting powerfully on the fauces and lungs. Dose, on sugar, one or two drops.

 Medical Herbalism journal and medherb.com