The essays on the _tarantula_ and _mad dog_, are likewise considerably enlarged in the last impression; especially the latter, in which is now comprehended a regular and elegant history of the symptoms attending the bite of this enraged animal, the reason of the consequent _hydrophobia_, and more extensive directions for the cure: also an accurate description of the _lichen cinereus terrestris_, its efficacy, and manner of acting. A composition of equal parts of this plant and black pepper, was inserted, at our author’s desire, into the London dispensatory, in the year 1721, under the title of _pulvis antilyssus_, which he afterwards altered by using two parts of the former, and only one of the latter, as it now stands: in 1735 he also recommended the use of this medicine in a loose sheet, intitled, _a certain cure for the bite of a mad dog_. In treating of poisonous minerals, exclusive of what is added concerning mercurial unctions, our author has given a new analysis of the antient and modern _arsenic_; and his essay on deliterious plants, has afforded him an opportunity of enquiring into the _cicuta_, so much in use of old for killing, especially at Athens, and which is said to have been administered to _Socrates_ in consequence of his condemnation. To this he has likewise subjoin’d an appendix, concerning the mischievous effects of the simple water distilled from the _lauro-cerasus_, or common laurel, which were first observed some years since in _Ireland_, where, for the sake of its flavour, it was frequently mixed with brandy.--His observations upon venemous exhalations, are not less extended, nor ought the, as well useful as ornamental, plates added to this last edition, to pass unnoticed, particularly, “The anatomical description of the parts in a viper, and in a rattlesnake, which are concerned in their poison,” by our great anatomist the learned and ingenious Dr. Nichols. In 1703 Dr. _Mead_ communicated to the royal society, a letter published in Italy in 1687 (a copy of which he met with in the course of his travels) from Dr. Bonomo to Seignor Redi, containing some observations concerning the worms of human bodies;[9] whereby it is intended to prove, that the disease, we call the itch, proceeds merely from the biting of these animalcules: this opinion is espoused by our author in one of his latest performances,[10] wherein therefore he directs only _topical_ applications for the cure of this troublesome disease. [9] An abstract of part of this letter was inserted in the before-cited number of the philosophical transactions. Vid. supra p. 10. [10] Monita & præcepta medica, p. 211, &c.