Castor Oil.
The supposed identity of the Palma Christi tree, from the seeds of which castor oil is obtained, with the Hebrew “kikaion” is mentioned in the note on Jonah’s “gourd” in the section “Pharmacy in the Bible.” It is not doubtful that the plant was the same as the “kiki” of Herodotus, and the “kiki” or “kroton” of Dioscorides. Avicenna quotes a reference to the seeds from Dioscorides, from which, he says, is pressed the oil of kiki “which is the oil of Alkeroa.” Other Arab authors use the term “al-keroa” for the Greek “kiki.” A frequent Latin name for the Palma Christi was “kikinum,” or “cicinum.”
Castor Oil Plant.
The earliest allusion to the oil is found in Herodotus (“Hist. Euterpe,” sec. 94), where we read “The inhabitants of the marshy grounds in Egypt make use of an oil which they term the ‘kiki,’ expressed from the Sillicyprian plant. In Greece this plant springs spontaneously without any cultivation; but the Egyptians sow it on the banks of the river and the canals; it there produces fruit in great abundance, but of a very strong odour. When gathered they obtain from it, either by friction or pressure, an unctuous liquid which diffuses an offensive smell, but for burning it is equal in quality to the oil of olives.”
From this and other references it is clear that the Egyptians held the Palma Christi plant in high esteem, and this would hardly have been the case if it was only used for the extraction of an inferior burning oil. As is stated in another section, Ebers guesses that an aperient medicine made from the fruit of the kesebt tree may have meant the ricinus seeds. The seeds of the Palma Christi, too, have been frequently found in sarcophagi; evidence that they had acquired a high reputation of some kind.
Hippocrates apparently tried to reduce the acridity of the seeds so as to make them more useful as purgatives. Dioscorides alludes to their purgative properties, but only contemplates the external employment of the oil in medicine. Pliny, however, is more explicit. Chapter xli., of Book 23 begins with the sentence: “Oleum cicinum bibitur ad purgationes ventris cum pari calidæ mensura.” The whole passage is of interest. The following is the translation of it given in Bohn’s “Classical Library” (Dr. Bostock): “Castor oil taken with an equal quantity of warm water acts as a purgative upon the bowels. It is said, too, that as a purgative it acts particularly upon the regions of the diaphragm (precordia). It is useful for diseases of the joints, all kinds of indurations, affections of the uterus and ears, and for burns, employed with the ashes of the murex; it heals itch, scabs, and inflammations of the fundament. It improves the complexion also, and by its fertilising tendencies promotes the growth of the hair. The cicus or seed from which this oil is made no animal will touch, and from these grape-like seeds wicks are made which burn with a peculiar brilliancy. The light, however, that is produced by the oil is very dim, in consequence of its extreme thickness. The leaves are applied topically with vinegar for erysipelas. Fresh gathered they are used by themselves for diseases of the mamillæ and defluxions. A decoction of them in wine with polenta and saffron is good for inflammations of various kinds. Boiled by themselves and applied to the face for three successive days they improve the complexion.”
In Egypt and Rome, therefore, Ricinus was evidently esteemed; and though as a medicine they dropped largely out of use, it is clear from old English physic books that a traditional reputation was always associated with both the seeds and the oil. Gerard, in his “Herbal,” and Piso, in an account of the natural history of the West Indies, both recommend them, the former in broth, the latter in the form of a tincture made with brandy for colic and constipation. Gerard states that the Palma Christi “of America” grew in his garden (in Holborn) and in many other gardens likewise. The seeds, however, came to be regarded as dangerous, and were clearly but little used in orthodox medicine. Quincy (1724) refers to them as “hardly ever met with in practice, unless amongst empirics and persons of no credit.”
In 1764, however, Dr. Peter Canvane, of Bath, who had practised for seven years in the West Indies, published a treatise entitled “A Dissertation on the Oleum Palmæ Christi, sive Oleum Ricini, or (as it is commonly call’d) Castor Oil,” in which he warmly recommended the oil as a gentle purgative, particularly in cases of “dry belly ache.” His advocacy soon took effect, for in the second edition of his treatise published in 1769, he says it had become officinal, by which he meant was sold in the shops, “at Apothecaries Hall and several other shops in London and Bath.” Dr. Odier, of Geneva, who visited England in 1776, became then acquainted with the medicine, and subsequently brought it to the notice of Continental physicians. It was admitted into the London Pharmacopœia in 1788.
The name “Ricinus” was in Latin the name of the parasite known as the dog-tick, Ixodes ricinus, and was transferred to the Palma Christi seeds because of their resemblance to the insect. In Greek the same insect was called the kroton, and Theophrastus and Dioscorides describe the Palma Christi seeds as kroton seeds. Curiously the name kroton has been applied in America to the cockroach, not from any association with ticks, but from a belief that the insects came from the Croton River when the water from that source was brought to New York in 1842. The name of castor oil is supposed to have been given to the oil in consequence of a mistaken idea in the Western Indies that the plant which yielded the seeds was Agnus Castus. There was, however, a castor oil and compound castor oil in medicinal use in England and other countries until the eighteenth century. The simple oil was made by digesting castorum in oil and boiling it with wine until the latter had all evaporated. The compound oil contained besides a number of aromatic gums and spices. Possibly the taste of the oil from the Palma Christi seeds recalled that from the old oil of castor, and the name may thus have been transferred.