Page:Micrographia - or some physiological descriptions of minute bodies made by magnifying glasses with observations and inquiries thereupon.djvu/142

Rh as B. If a fifth be joyn'd to them on either side in as close a position as it can, which is the propriety of the Texture, it makes a Trapezium, or four-sided Figure, two of whole angles are 120. and two 60. degrees, as C. If a sixth be added, as before, either it makes an æquilateral triangle, as D, or a Rhomboeid, as E, or an Hex-angular Figure, as F, which is compos'd of two primary Rhombes. If a seventh be added, it makes either an æquilatero-hexagonal Figure, as G, or some kind of six-sided Figure, as H, or I. And though there be never so many placed together, they may be rang'd into some of these lately mentioned Figures, all the angles of which will be either 60. degrees, or 120. as the figure K. which is an æquiangular hexagonal Figure is compounded of 12. Globules, or may be of 25, or 27, or 36, or 42, &c. and by these kinds of texture, or position of globular bodies, may you find out all the variety of regular shapes, into which the smooth surfaces of Alum are form'd, as upon examination any one may easily find; nor does it hold only in superficies, but in solidity also, for it's obvious that a fourth Globule laid upon the third in this texture, composes a regular Tetrahedron, which is a very usual Figure of the Crystals of Alum. And (to hasten) there is no one Figure into which Alum is observ'd to be crystallized, but may by this texture of Globules be imitated, and by no other.

I could instance also in the Figure of Sea-salt, and Sal-gem, that it is compos'd of a texture of Globules, placed in a cubical form, as L, and that all the Figures of those Salts may be imitated by this texture of Globules and by no other whatsoever. And that the forms of Vitriol and of Salt-Peter, as also of Crystal, Hore-frost, &c. are compounded of these two textures, but modulated by certain proprieties: But I have not here time to insist upon, as I have not neither to shew by what means Globules come to be thus context, and what those Globules are, and many other particulars requisite to a full and intelligible explication of this propriety of bodies. Nor have I hitherto found indeed an opportunity of prosecuting the inquiry so farr as I design'd; nor do I know when I may, it requiring abundance of time, and a great deal of assistance to go through with what I design'd; the model of which was this:

First, to get as exact and full a collection as I could, of all the differing kinds of Geometrical figur'd bodies, some three or four several bodies of each kind.

Secondly, with them to get as exact a History as possibly I could learn of their places of Generation or finding, and to enquire after as many circumstances that tended to the Illustrating of this Enquiry, as possibly I could observe.

Thirdly, to make as many trials as upon experience I could find requisite, in Dissolutions and Coagulations of several crystallizing Salts; for the needfull instruction and information in this Enquiry.

Fourthly, to make several trials on divers other bodies, as Metals, Minerals, and Stones, by dissolving them in several Menstruums, and crystalizing them, to see what Figures would arise from those several Compositums. Rh