On Poisonous Plants

...harmful to some animals, while to others they are either not harmful at all, or only slightly so. Animals from the class of Wild Beasts that are born blind—such as the Dog, Wolf, Fox, Cat, and Hyena—are all easily killed by the Strychnine Tree original: "Nuce Vomica" and the seed pods of Spurge original: "Euphorbiæ" and Poison Ivy original: "Toxicodendri", just as Pigs are killed by pepper, and Geese by parsley. Spurge is eaten without harm by sheep and goats, while cattle in Africa often perish from it. Furthermore, all parts of the same plant are not always equally harmful or poisonous; nor does the same part, in one and the same plant, occur as equally harmful throughout its entire lifespan. The younger Pokeberry original: "Phytolacca" can be eaten safely without harm, but when more mature it becomes highly corrosive; and the delicious ripe fig, which is very sweet and nourishing, if devoured when immature, is exceedingly acrid and poisonous, provoking dangerous vomiting and diarrhea. We must also observe that a plant, poisonous by its own nature, can be rendered edible and healthful through preparation and cultivation, such as the roots of Wild Arum, Water-lily, the Potato original: "Solani tuberosi", and Rampion Bellflower, or the fruit of the Eggplant original: "Melongenæ".

Generally, it may be affirmed that no true medicines or poisons can acquire the nature of nutrients within the human body; nevertheless, through the long and prudent continued use of these substances, it can be brought about that nature becomes, as it were, gradually accustomed to them. By ascending slowly from a smaller to a larger dose, an antidote original: "alexipharmacum," here referring to a potent substance or counter-poison may sometimes be swallowed without harm, which would undoubtedly kill one who is unaccustomed to it. For habit becomes, as it were, a second nature. This is the reason why various nations inhabiting Asia can swallow such a great quantity of poisonous opium daily; why almost all peoples love the use of tobacco—which is no less unpleasant than it is poisonous—some even to the point of delirium; and why a remedy that is frequently repeated, such as a laxative made from Jalap, Rhubarb, or Senna, eventually becomes ineffective.