The cause of all which regular Figures (and of hundreds of others, namely of _Salts_, _Minerals_, _Metals_, &c. which I could have here inserted, would it not have been too long) seems to be deducible from the same Principles, which I have (in the 13. _Observation_) hinted only, having not yet had time to compleat a _Theory_ of them. But indeed (which I there also hinted) I judge it the second step by which the _Pyramid_ of natural knowledge (which is the knowledge of the form of bodies) is to be ascended: And whosoever will climb it, must be well furnish’d with that which the Noble _Verulam_ calls _Scalam Intellectus_; he must have scaling Ladders, otherwise the steps are so large and high, there will be no getting up them, and consequently little hopes of attaining any higher station, such as to the knowledge of the most simple principle of Vegetation manifested in Mould and Mushromes, which, as I elsewhere endeavoured to shew, seems to be the third step; for it seems to me, that the Intellect of man is like his body, destitute of wings, and cannot move from a lower to a higher and more sublime station of knowledg, otherwise then step by step, nay even there where the way is prepar’d and already made passible; as in the _Elements of Geometry_, or the like, where it is fain to climb a whole _series_ of Propositions by degrees, before it attains the knowledge of one _Probleme_. But if the ascent be high, difficult and above its reach, it must have recourse to a _novum organum_, some new engine and contrivance, some new kind of _Algebra_, or _Analytick Art_ before it can surmount it. * * * * * Observ. XV. _Of _Kettering-stone_, and of the pores of _Inanimate_ bodies._