Micrographia — Observ. XIV.

* * * * * Observ.

XIV.

_Of several kindes of frozen _Figures_.

_ I have very often in a Morning, when there has been a great _hoar-frost_, with an indifferently magnifying _Microscope_, observ’d the small _Stiriæ_, or Crystalline beard, which then usually covers the face of most bodies that lie open to the cold air, and found them to be generally _Hexangular prismatical_ bodies, much like the long Crystals of _Salt-peter_, save onely that the ends of them were differing: for whereas those of _Nitre_ are for the most part _pyramidal_, being terminated either in a point or edge; these of Frost were hollow, and the cavity in some seem’d pretty deep, and this cavity was the more plainly to be seen, because usually one or other of the six _parallelogram_ sides was wanting, or at least much shorter then the rest.

But this was onely the Figure of the _Bearded hoar-frost_; and as for the particles of other kinds of _hoar-frosts_, they seem’d for the most part irregular, or of no certain Figure.

Nay, the parts of those curious branchings, or _vortices_, that usually in cold weather tarnish the surface of Glass, appear through the _Microscope_ very rude and unshapen, as do most other kinds of frozen _Figures_, which to the naked eye seem exceeding neat and curious, such as the Figures of _Snow_, frozen _Urine_, _Hail_, several _Figures_ frozen in common Water, &c. Some Observations of each of which I shall hereunto annex, because if well consider’d and examin’d, they may, perhaps, prove very instructive for the finding out of what I have endeavoured in the preceding Observation to shew, to be (next the _Globular Figure_ which is caus’d by _congruity_, as I hope I have made probable in the sixth _Observation_) the most simple and plain operation of Nature, of which, notwithstanding we are yet ignorant.

I.

_Several Observables in the _six-branched_ Figures form’d on the surface of Urine by freezing.

_ 1 [11]The Figures were all frozen almost even with the surface of the _Urine_ in the Vessel; but the bigger stems were a little _prominent_ above that surface, and the parts of those stems which were nearest the center (a) were biggest above the surface.

2 I have observ’d several kinds of these Figures, some smaller, no bigger then a Two-pence, others so bigg, that I have by measure found one of its stems or branches above four foot long; and of these, some were pretty round, having all their branches pretty neer alike; other of them were more extended towards one side, as usually those very large ones were, which I have observ’d in Ditches which have been full of foul water.

3 None of all these Figures I have yet taken notice of, had any regular position in respect of one another, or of the sides of the Vessel; nor did I find any of them equally to exactness extended every way from the center a. 4 Where ever there was a center, the branchings from it, ab, ac, ad, ae, af, ag, were never fewer, or more then six, which usually concurr’d, or met one another very neer in the same point or center, a; though oftentimes not exactly; and were enclin’d to each other by an angle, of very near sixty degrees, I say, very neer, because, though having endeavoured to measure them the most accurately I was able, with the largest Compasses I had, I could not find any sensible variation from that measure, yet the whole six-branched Figure seeming to compose a solid angle, they must necessarily be somewhat less.

5 The middle lines or stems of these branches, ab, ac, ad, ae, af, ag, seem’d somewhat whiter, and a little higher then any of the _intermediate_ branchings of these Figures; and the center a, was the most _prominent_ part of the whole Figure, seeming the _apex_ of a solid angle or _pyramid_, each of the six plains being a little enclin’d below the surface of the _Urin_.

6 The lateral branchings issuing out of the great ones, such as op, mq, &c. were each of them inclin’d to the great ones, by the same angle of about sixty degrees, as the great ones were one to another, and always the bigger branchings were _prominent_ above the less, and the less above the least, by proportionate _gradations_.

7 The _lateral_ branches shooting out of the great ones, went all of them from the center, and each of them was parallel to that great branch, next to which it lay; so that as all the branches on one side were parallel to one another, so were they all of them to the _approximate_ great branch, as po, qr, as they were parallel to each other, and shot from the center, so were they parallel also to the great branch ab.

8 Some of the stems of the six branches proceeded straight, and of a thickness that gradually grew sharper towards the end, as ag.

9 Others of the stems of those branches grew bigger and knotty towards the middle, and the branches also as well as stems, from Cylinders grew into Plates, in a most admirable and curious order, so exceeding regular and delicate, as nothing could be more, as is visible in ab, ac, ad, ae, af, but towards the end of some of these stems, they began again to grow smaller and to recover their former branchings, as about k and n. 10 Many of the _lateral_ branches had _collateral_ branches (if I may so call them) as qm had many such as st, and most of those again _subcollateral_, as vw, and these again had others less, which one may call _laterosubcollateral_, and these again others, and they others, &c. in greater Figures.

11 The branchings of the main Stems joyn’d not together by any regular line, nor did one side of the one lie over the other side of the other, but the small _collateral_ and _subcollateral_ branches did lie at top of one another according to a certain order or method, which I always observ’d to be this.

12 That side of a _collateral_ or _subcollateral_, &c. branch, lay over the side of the _approximate_ (as the feathers in the wing of a Bird) whose branchings proceeded parallel to the last biggest stem from which it sprung, and not to the biggest stem of all, unless that were a second stem backwards.

13 This rule that held in the branchings of the _Sexangular Figure_ held also in the branchings of any other great or small stem, though it did not proceed from a center.

14 The exactness and curiosity of the figuration of these branches, was in every particular so transcendent, that I judge it almost impossible for humane art to imitate.

15 Tasting several cleer pieces of this _Ice_, I could not find any _Urinous_ taste in them, but those few I tasted, seem’d as _insipid_ as water.

16 A figuration somewhat like this, though indeed in some particulars much more curious, I have several times observ’d in _regulus martis stellatus_, but with this difference, that all the stems and branchings are bended in a most excellent and regular order, whereas in _Ice_ the stems and branchings are streight, but in all other particulars it agrees with this, and seems indeed nothing but one of these stars, or branched Figures frozen on _Urine_, distorted, or wreathed a little, with a certain proportion: _Lead_ also that has _Arsenick_ and some other things mixt with it, I have found to have its surface, when suffer’d to cool, figured somewhat like the branchings of _Urine_, but much smaller.

17 But there is a _Vegetable_ which does exceedingly imitate these branches, and that is, _Fearn_, where the main stem may be observ’d to shoot out branches, and the stems of each of these _lateral_ branches, to send forth _collateral_, and those _subcollateral_ and those _laterosubcollateral_, &c. and all those much after the same order with the branchings, divisions, and subdivisions in the branchings of these Figures in frozen _Urine_; so that if the Figures of both be well consider’d, one would ghess that there were not much greater need of a _seminal principle_ for the production of _Fearn_, then for the production of the branches of _Urine_, or the _Stella martis_, there seeming to be as much form and beauty in the one as in the other.

And indeed, this Plant of _Fearn_, if all particulars be well consider’d, will seem of as simple, and uncompounded a form as any _Vegetable_, next to _Mould_ or _Mushromes_, and would next after the invention of the forms of those, deserve to be enquir’d into; for notwithstanding several have affirm’d it to have seed, and to be propagated thereby; yet, though I have made very diligent enquiry after that particular, I cannot find that there is any part of it that can be imagin’d to be more seminal then another: But this onely here by the by: For the freezing Figures in _Urine_, I found it requisite, First, that the Superficies be not disturbed with any wind, or other commotion of the air, or the like.

Secondly, that it be not too long exposed, so as that the whole bulk be frozen, for oftentimes, in such cases, by reason of the swelling the of _Ice_, or from some other cause, the curious branched Figures disappear.

Thirdly, an artificial freezing with _Snow_ and _Salt_, apply’d to the outside of the containing Vessel, succeeds not well, unless there be a very little quantity in the Vessel.

Fourthly, If you take any cleer and smooth Glass, and wetting all the inside of it with _Urine_, you expose it to a very sharp freezing, you will find it cover’d with a very regular and curious Figure.

II.

_Observables in figur’d _Snow_.

_ Exposing a piece of black Cloth, or a black Hatt to the falling _Snow_, I have often with great pleasure, observ’d such an infinite variety of curiously figur’d _Snow_, that it would be as impossible to draw the Figure and shape of every one of them, as to imitate exactly the curious and Geometrical _Mechanisme_ of Nature in any one.

Some coorse draughts, such as the coldness of the weather, and the ill provisions, I had by me for such a purpose, would permit me to make, I have here added in the Second _Figure_ of the Eighth _Scheme_.

[12] In all which I observ’d, that if they were of any regular Figures, they were always branched out with six principal branches, all of equal length, shape and make, from the center, being each of them inclin’d to either of the next branches on either side of it, by an angle of sixty degrees.

Now, as all these stems were for the most part in one flake exactly of the same make, so were they in differing Figures of very differing ones; so that in a very little time I have observ’d above an hundred several cizes and shapes of these starry flakes.

The branches also out of each stem of any one of these flakes, were exactly alike in the same flake; so that of whatever Figure one of the branches were, the other five were sure to be of the same, very exactly, that is, if the branchings of the one were small _Perallelipipeds_ or Plates, the branchings of the other five were of the same; and generally, the branchings were very conformable to the rules and method observ’d before, in the Figures on _Urine_, that is, the branchings from each side of the stems were parallel to the next stem on that side, and if the stems were plated, the branches also were the same; if the stems were very long, the branches also were so, &c. Observing some of these figur’d flakes with a _Microscope_, I found them not to appear so curious and exactly figur’d as one would have imagin’d, but like Artificial Figures, the bigger they were magnify’d, the more irregularities appear’d in them; but this irregularity seem’d ascribable to the thawing and breaking of the flake by the fall, and not at all to the defect of the _plastick_ virtue of Nature, whose curiosity in the formation of most of these kind of regular Figures, such as those of _Salt_, _Minerals_, &c. appears by the help of the _Microscope_, to be very many degrees smaller then the most acute eye is able to perceive without it.

And though one of these six-branched Stars appear’d here below much of the shape described in the Third _Figure_ of the Eighth _Scheme_; yet I am very apt to think, that could we have a sight of one of them through a _Microscope_ as they are generated in the Clouds before their Figures are vitiated by external accidents, they would exhibit abundance of curiosity and neatness there also, though never so much magnify’d: For since I have observ’d the Figures of _Salts_ and _Minerals_ to be some of them so exceeding small, that I have scarcely been able to perceive them with the _Microscope_, and yet have they been regular, and since (as far as I have yet examin’d it) there seems to be but one and the same cause that produces both these effects, I think it not irrational to suppose that these pretty figur’d Stars of _Snow_, when at first generated might be also very regular and exact.

III.

_Several kinds of Figures in _Water_ frozen.

_ Putting fair Water into a large capacious Vessel of _Glass_, and exposing it to the cold, I observ’d after a little time, several broad, flat, and thin _laminæ_, or plates of _Ice_, crossing the bulk of the water and one another very irregularly, onely most of them seem’d to turn one of their edges towards that side of the Glass which was next it, and seem’d to grow, as ’twere from the inside of the Vessel inwards towards the middle, almost like so many blades of _Fern_.

Having taken several of these plates out of water on the blade of a Knife, I observ’d them figur’d much after the manner of _Herring bones_, or _Fern blades_, that is, there was one bigger stem in the middle like the back-bone, and out of it, on either side, were a multitude of small _stiriæ_, or _icicles_, like the smaller bones, or the smaller branches in _Fern_, each of these branches on the one side, were parallel to all the rest on the same side, and all of them seem’d to make an angle with the stem, towards the top, of sixty degrees, and towards the bottom or root of this stem, of 120. See the fourth _Figure_ of the 8. _Plate_.

I observ’d likewise several very pretty Varieties of Figures in Water, frozen on the top of a broad flat Marble-stone, expos’d to the cold with a little Water on it, some like feathers, some of other shapes, many of them were very much of the shape exprest in the fifth Figure of the 8. _Scheme_, which is extremely differing from any of the other Figures.

I observ’d likewise, that the shootings of _Ice_ on the top of Water, beginning to freeze, were in streight _prismatical_ bodies much like those of _roch-peter_, that they crost each other usually without any kind of order or rule, that they were always a little higher then the surface of the Water that lay between them; that by degrees those _interjacent_ spaces would be fill’d with _Ice_ also, which usually would be as high as the surface of the rest.

In flakes of _Ice_ that had been frozen on the top of Water to any considerable thickness, I observ’d that both the upper and the under sides of it were curiously quill’d, furrow’d, or grain’d, as it were, which when the Sun shone on the Plate, was exceeding easily to be perceiv’d to be much after the shape of the lines in the 6. _Figure_ of the 8. _Scheme_, that is, they consisted of several streight ends of parallel Plates, which were of divers lengths and angles to one another without any certain order.

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.

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