This section is from the book "An Experimental History Of The Materia Medica", by William Lewis.
Crowfoot: a plant with pentapetalous flowers set in five-leaved cups; followed each by a round cluster of naked seeds, It is perennial a. Flammula; Ranunculus longifolius palus-tris minor C. B. Ranunculus Flammula Linn. Smaller water crowfoot or spearwort: with fibrous roots, long narrow leaves acuminated at both ends, and leaning or procumbent stalks. It grows in watery places or moist meadows, and flowers in June,
1. Ranunculus. Ranunculus pratensis radice verticilli modo rotunda C. B. Ranunculus bul-bofus Linn. Bulbous crowfoot, butter flower, gold cup: with a round tuberous root about the size of an olive; the leaves divided commonly into three segments, and these further subdi-vided; the stalks erect: the flowers of a bright glossy yellow, and their cups turned downwards. It is common in pasture grounds, and flowers in May.
The roots and leaves of these plants are of no considerable smell, but in taste highly acrid and fiery, Taken internally, they appear to be deleterious, even when so far freed from the caustic matter, by boiling in water, as to dis-cover no ill quality to the palate. The effluvia likewise even of the less acrid species or varieties cultivated in gardens, when freely inspired, have occasioned headachs, anxieties, vomitings, and spasmodic symptoms. The leaves and roots, applied externally, inflame and exulcerate or vesicate the part, and are liable to affect also the adjacent parts to a considerable extent (a): they have sometimes, particularly among em-pyrics and the common people, supplied the place of the far safer and not lets effectual vefi-catory, cantharides, for procuring an ulcer and discharge of serum, in sciaticas and some fixt pains of the head. Their pungency is dimi-nished by drying, and by long keeping seems to be dissipated or destroyed.