If we may venture to offer a conjecture upon this subject, we are inclined to consider the origin of this opinion to have been derived from the frequency with which the toad entered into the composition of spells or charms, into philtres or love potions, and which, like the bat and the owl, most probably derived its magical character from the gloom and solitude of its habitation. _Shakspeare_ has accordingly introduced this reptile into the witches’ enchanted cauldron, in _Macbeth_. “Round about the cauldron go; In the poison’d entrails throw. Toad that under coldest stone Days and nights hast thirty-one Swelter’d venom sleeping got, Boil thou first i’ the charmed pot!” This opinion receives further strength when it is considered how frequently poisons were administered under the insidious form of charms or incantations.[128] It has, however, been shewn by late experiments that the toad has, under particular circumstances, the power of ejecting from the surface of the body an acrid secretion which excoriates the hands of those that come in contact with it; and this fact may perhaps have assisted in supporting the general belief respecting the poisonous nature of this reptile. _Pelletier_ has ascertained, that this corrosive matter, contained in the vesicles which cover the skin of the common toad, (_Rana Bufo_) has a yellow colour, and an oily consistence, and to consist of,—1st, an acid partly united to a base, and constituting 1/20th part of the whole. 2d, very bitter fatty matter. 3d, an animal matter bearing some analogy to gelatine. It would also appear from the writings of _Dioscorides_, _Galen_, _Nicander_, _Ætius_, _Ælian_, and _Pliny_, that the ancients derived a very energetic poison from the Sea Hare, _Lepus Marinus_,—the _Aplysia Depilans_ of _Linnæus_; and, if we may credit _Philostratus_, it was with such a poison that _Titus_ was killed by _Domitian_. There is, however, ample ground for supposing that the poisons of the ancients were, for the most part, obtained from the vegetable kingdom, and from the class of Narcotic plants;[129] that they were compounded of a great variety of such ingredients, together with others that were quite inert and useless, and which merely served to disguise their composition. Ancient writers also allude to the blood of the bullock as a poison; _Themistocles_ is said by _Plutarch_ to have destroyed himself by this fluid; and _Strabo_ states that _Midas_ died of drinking the hot blood of this animal, which he did, as _Plutarch_ mentions, to free himself from the numerous ill dreams which continually tormented him. Some historians assign the death of _Hannibal_ to the same draught.