Seâ:. 9.

Of Cryflallization.

Figures, they are obvious to everyBeholder : and their Beauty and Va-riety are & admirable, that there isIcarce any thing in nature, whichcan entertain the Eye more agree-ably. The Figures of thefe are fome-times feen by the naked Eye, butby the help of Micro/copes are dif-cern'd much better. In common Saltwe plainly difcover Quadrilateral"Pyramids with fquare Baies. InSugar, the fame Pyramids, with ob-long and rectangular Baies. In¿llum, they rife with fix iides, fup-ported with a hexagonal Bafe. TheCryftals of Vitriol very much re-ferable Icicles, united one to ano-ther with great variety, amongwhich lie ibme Polygons, as maybe difcover'd with the naked Eye.Sal Armoniac very elegantly imitatesthe Branches of a Tree, and that ofHartfliornXooks like a Quiver of Ar-rows. Glauber's Sal Miraèile, whichis made of common Salt and Vitriol,exhibits the Figure of both thoièSalts.Nitre appears in certain PrifmaticalColumns, nor much unlike Bundlesof Sticks; among which there areinterfpers'd fome Rhomboides, andPentagons, which feem to comevery near thoiè of common Salt.Hence Lemery very juitlyremark'd,that Nitre could not be purify'd byany Art or Contrivance whatever,but iomethingof a Sal Gem, or FojplSalt, would (lick to it. Bur Salt ofTin out-does all for Beauty, in whichare Lines like little Needles, fpread-ing themfelves every where from aPoint as from a Center, lb as to re-prefent a Star, much like what wefee in the Regulus Marti s.

But this is very peculiar in thefeSalts, that let them be ever lb di-vided and reduced into minute Par-ticles, yet when they are form'd intoCryftals, they each of them re-ajTume their proper Shape : fo that

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one might as eafily diveft and de-prive them of their Saltnefi, as oftheir Figure. This being an immu-table and perpetual Law, by know-ing the Figure of the Qyftals, wemay underftand what the Texture ofthe Particles ought to be, whichcan form thofe Cryirals. And onthe other hand, by knowing theTexture of the Particles, we maydetermine the Figures of the Crys-tals: For fince the Figures of themoft Ample Parts remain always thelame, 'tis evident the Figures whichthey run into, when compoundedand united, muft be uniform andconfiant. And ilnce the Force ofAttraction is ftronger on one fide ofthe fame Particle than another, therewill conftantly be a greater Concre-tion of Salts upon thofe Sides, whichattraft moreftrongly. From henceit may be eaiily demonflrated, thatthe Figure of the lean Particles isintirely different from that which ap-pears m the Cr)ßal. But we muftleave this to the Mathematicians,left we fhould ièem to invade theirProvince.

From this Theory of the Afïbcia-tion and Combination of Salts, wemay learn how to avoid iuch Con-junctions in thofe Preparations,where the Nature of the Medicinerequires them to be kept afunder,and in a Sute oí Solution; as inSyrups, Confections, and Electuaries.For in thefe Forms, as much Careis neceiTary to pre vent the Sugar orHoney contain'd in their Compofi-tion from running into fuch Com-binations, or Candying, as it is uiu-ally term'd, as in the former to aC-lift fuch a Conjunction.

For this purpofe, ia the Prepara-tion of thofe Medicines, every partought to- be manag'd fo as to pre-vent the too near Approach of thai«attrs-âivs iâline Partklçs to one aao' P. ther.