It would serve little purpose to deal in detail with the various exponents of the doctrine of signatures, such, for example, as Johann Popp, who in 1625 published a herbal written from this standpoint, and containing also some astrological botany. We will only now refer to one of the later champions of the signatures of plants, an English herbalist of the seventeenth century, who made the subject peculiarly his own. This was William Cole[37], a Fellow of New College, Oxford, who lived and botanised at Putney in Surrey. He seems to have been a person of much character, and his vigorous arguments would often be very telling, were it possible to admit the soundness of his premisses. William Cole carried the doctrine of signatures to as extreme a point as can well be imagined. His account of the Walnut, from his work ‘Adam in Eden,’ 1657, may be quoted as an illustration: “_Wall-nuts_ have the perfect Signature of the Head: The outer husk or green Covering, represent the _Pericranium_, or outward skin of the skull, whereon the hair groweth, and therefore salt made of those husks or barks, are exceeding good for wounds in the head. The inner wooddy shell hath the Signature of the Skull, and the little yellow skin, or Peel, that covereth the Kernell of the hard _Meninga_ and _Pia-mater_, which are the thin scarfes that envelope the brain. The _Kernel_ hath the very figure of the Brain, and therefore it is very profitable for the Brain, and resists poysons; For if the Kernel be bruised, and moystned with the quintessence of Wine, and laid upon the Crown of the Head, it comforts the brain and head mightily.” In Cole’s writings we meet with instances of a curious confusion of thought, which characterised the doctrine of signatures. The signature in some cases represents an animal injurious to man, and is taken to denote that the plant in question will cure its bites or stings. For instance, “That Plant that is called _Adders tongue_, because the stalke of it represents one, is a soveraigne wound Herbe to cure the biting of an Adder.” In other cases, the signature represents one of the organs of the human body, and indicates that the plant will cure diseases of that organ. For example, “_Heart Trefoyle_ is so called, not onely because the Leafe is Triangular like the Heart of a Man, but also because each Leafe containes the perfect Icon of an Heart, and that in its proper colour, _viz._ a flesh colour. It defendeth the Heart against the noisome vapour of the Spleen.”