Of sundry popular Tenets concerning Mineral, and vegetable bodies, generally held for truth; which examined, prove either false, or dubious. CHAPTER I Of Crystal. Hereof the common Opinion hath been, and still remaineth amongst us, that Crystal is nothing else but Ice or Snow concreted, and by duration of time, congealed beyond liquation. Of which assertion, if prescription of time, and numerosity of Assertors, were a sufficient demonstration, we might sit down herein, as an unquestionable truth; nor should there need _ulterior_ disquisition. For few Opinions there are which have found so many friends, or been so popularly received, through all Professions and Ages. _Pliny_ is positive in this Opinion: _Crystallus sit gelu vehementius concreto_: the same is followed by _Seneca_, elegantly described by _Claudian_, not denied by _Scaliger_, some way affirmed by _Albertus_, _Brasavolus_, and directly by many others. The venerable Fathers of the Church have also assented hereto; As _Basil_ in his _Hexameron_, _Isidore_ in his Etymologies, and not only _Austin_ a Latine Father, but _Gregory_ the Great, and _Jerome_ upon occasion of that term expressed in the first of _Ezekiel_. [Sidenote: _That Crystal is not Ice or Snow congealed._] All which notwithstanding, upon a strict enquiry, we find the matter controvertible, and with much more reason denied then is as yet affirmed. For though many have passed it over with easie affirmatives, yet are there also many Authors that deny it, and the exactest Mineralogists have rejected it. _Diodorus_ in his eleventh Book denieth it, (if Crystal be there taken in its proper acception, as _Rhodiginus_ hath used it, and not for a Diamond, as _Salmatius_ hath expounded it) for in that place he affirmeth; _Crystallum esse lapidem ex aqua pura concretum, non tamen frigore sed divini caloris vi_. _Solinus_ who transcribed _Pliny_, and therefore in almost all subscribed unto him, hath in this point dissented from him. _Putant quidam glaciem coire, et in Crystallum corporari, sed frustra._ _Mathiolus_ in his Comment upon _Dioscorides_, hath with confidence rejected it. The same hath been performed by _Agricola de natura fossilium_; by _Cardan_, _Bœtius de Boot_, _Cæsius Bernardus_, _Sennertus_, and many more.