THE SECOND BOOK,

BEGINNING THE PARTICULAR PART.

OF POPULAR AND RECEIVED TENETS CONCERNING MINERAL AND VEGETABLE BODIES.

CHAPTER I.

That Crystal is nothing else but Ice strongly congealed.

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 fit gelu vehementius concreto the same is followed by Seneca, elegantly described by Claudian, not denied by Scaliger, some way affirmed by Albertus, Brassavolus, and directly by many others.2 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 Jerom upon occasion of that term expressed in the first of Ezekiel.

1 Crystallus fit gelu, &c.] This opinion is given by Pliny, Hist. Nat. lib. xxxvii. cap. 2.—Br.

2 by many others.] Thucydides clearly uses the word кρúσraλλos in the sense of ice; See Hist. iii. 23.-4to. vol. 1, p. 438.

All which notwithstanding, upon a strict enquiry, we find the matter controvertible, and with much more reason denied, than is as yet affirmed. For though many have. passed it over with easy affirmatives, yet there are 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 Salmasius 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. Matthiolus, in his comment upon Dioscorides, hath with confidence rejected it.3 The same hath been performed by Agricola, De natura fossilium, by Cardan, Boëtius de Boot, Casius Bernardus, Sennertus, and many more.

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Now, besides authority against it, there may be many reasons, deduced from their several differences, which seem to overthrow it. And first a difference is probable in their concretion. For, if crystal be a stone (as in the number thereof it is confessedly received), it is not immediately concreted by the efficacy of cold, but rather by a mineral spirit and lapidifical principles of its own; and, therefore, while it lay in solutis principiis, and remained in a fluid body, it was a subject very unapt for proper conglaciation; for mineral spirits do generally resist, and scarce submit thereto. So we observe that many waters and springs will never freeze,5 and many parts in rivers and lakes, where

3 with confidence rejected it.] "With confidence, and not without reason, rejected it."-Ed. 1646.

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as in the number thereof it is, &c.] i. e. in the number whereof it is, &c.

Ross, with his usual wrong-headedness, argues stoutly for the ancient opinion. "The cold of some waters," he observes, "metamorphose sticks, leaves, and trees, pieces of leather, nutshells, and such like stuff into stones; why then may not cold convert ice into a higher degree of hardness, and prepare it for reception of a new form, which gives it the essence and name of crystal ?"-Arcana, p. 189.

5 many waters and springs will never freeze.] Our author is mistaken in ascribing this phenomenon to the mineral contents of the water ex

there are mineral eruptions, will still persist without congelation as we also observe in aqua fortis, or any mineral solution, either of vitriol, alum, saltpetre, ammoniac, or tartar, which, although to some degree exhaled, and placed in cold conservatories, will crystallize and shoot into white and glacious bodies: yet is not this a congelation primarily effected by cold, but an intrinsical induration from themselves; and a retreat into their proper solidities, which were absorbed by the liquor, and lost in a full imbibition thereof before. And so, also, when wood and many other bodies do petrify, either by the sea, other waters, or earths abounding in such spirits, we do not usually ascribe their induration to cold, but rather unto salinous spirits, concretive juices, and causes circumjacent, which do assimilate all bodies not indisposed for their impressions.

But ice is only water congealed by the frigidity of the air, whereby it acquireth no new form, but rather a consistence or determination of its diffluency, and amitteth not its essence, but condition of fluidity. Neither doth there any thing properly conglaciate but water, or watery humidity; for the determination of quicksilver is properly fixation, that

hibiting it: no springs are so strongly impregnated with mineral substances as to have their freezing points affected by it in any considerable degree. The true cause of the phenomenon is, in the case of springs and lakes, their depth, and in that of rivers, their depth in conjunction with the rapidity with which they flow. For, owing to the mobility of the particles of water, and to the circumstance that, like all other bodies, it becomes heavier, in consequence of its contraction in bulk, in proportion as its temperature is reduced (with a particular exception, which it is unnecessary now to mention), when the surface or upper portion of the water gives out its heat to the atmosphere, on account of the temperature of that medium becoming inferior to its own, the portion of water so cooled down, becoming heavier than the subjacent portion, sinks towards the bottom, and an uncooled portion takes its place, which, in its turn, is cooled, and rendered heavier by the same process. Until, therefore, the whole of the water has been reduced to the freezing point by the continuance of this operation, no ice can form upon it; for, until then, the temperature of that portion which is in contact with the atmosphere will be above the freezing point. In the case of deep wells and lakes, this occupies so long a time, that, in temperate climates, the cold season has passed away, and the temperature of the atmosphere has ceased to be inferior to that the upper portion of the water, before the whole has been reduced to the freezing point.—Br.

of milk coagulation, and that of oil and unctious bodies only incrassation. And, therefore, Aristotle makes a trial of the fertility of human seed, from the experiment of congelation; for that, saith he, which is not watery and improlifical will not conglaciate which, perhaps, must not be taken strictly, but in the germ and spirited particles; for eggs, I observe, will freeze in the albugineous part thereof. And upon this ground Paracelsus, in his Archidoxis, extracteth the magistery of wine; after four months' digestion in horse-dung, exposing it unto the extremity of cold, whereby the aqueous parts will freeze, but the spirit retire, and be found uncongealed in the centre.

But whether this congelation be simply made by cold, or also by co-operation of any nitrous coagulum, or spirit of salt, the principle of concretion, whereby we observe that ice may be made with salt and snow by the fire-side, as is also observable from ice made by saltpetre and water, duly mixed and strongly agitated, at any time of the year, were a very considerable enquiry. For thereby we might clear the generation of snow, hail, and hoary frosts, the piercing quali

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eggs, I observe, &c.] That point in the Chalaza, the spark of vivification, I wish it might freeze: it would rid my trees from caterpillars, which can continue their noxious species, by their hybernating eggs.Robinson's Endoxa.

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or also by co-operation of any nitrous coagulum.] The doubt here expressed, whether the congelation of water is simply owing to cold, or whether the operation of cold may not be aided by saltpetre, or some analogous principle, is a remnant of the notions entertained of that salt by the alchemists, and the older operators in true chemistry who immediately succeeded them, of both whose ideas on such subjects our author retained a few, though (considering the state of science in his time) but very few indeed, and those of minor importance only. The arguments which he adduces in favour of this doubt are as fallacious as the supposition itself, which it involves, "That ice may be made with salt and snow by the fire-side,” arises, not from any peculiar congealing virtue in the salt, but merely from the circumstance that the affinity it has for water produces a rapid liquefaction of the snow, which, robbing the surrounding bodies of their heat, in order itself to assume the liquid form (their sensible heat thus becoming latent in the resulting water) produces the cold. The case is similar with respect to the "ice made by saltpetre and water;" for here, the water subjected to experiment is reduced to the solid form by the abstraction of its sensible heat, consequent upon the liquefaction of the salt, in the solution of which it becomes latent.-Br.

ties of some winds, the coldness of caverns, and some cells. We might more sensibly conceive how saltpetre fixeth the flying spirits of minerals in chemical preparations, and how by this congealing quality it becomes an useful medicine in fevers.8

Again, the difference of their concretion is collectible from their dissolution, which being many ways performable in ice, is few ways effected in crystal. Now the causes of liquation are contrary to those of concretion; and, as the atoms and indivisible parcels are united, so are they in an opposite way disjoined. That which is concreted by exsiccation or expression of humidity,1 will be resolved by humectation, as earth, dirt, and clay; that which is coagulated by a fiery siccity, will suffer colliquation from an aqueous humidity, as salt and sugar, which are easily dissoluble in water, but not without difficulty in oil and well rectified spirits of wine. That which is concreted by cold, will dissolve by a moist heat, if it consist of watery parts, as gums arabic, tragacanth, ammoniac, and others, in an airy heat or oil, as all resinous bodies, turpentine, pitch, and frankincense; in both, as gummy resinous bodies, mastic, camphor, and storax; in neither, as neutrals, and bodies anomalous hereto, as bdellium, myrrh, and others. Some by a violent dry heat, as metals; which although corrodible by waters, yet will they not suffer a liquation2 from the powerfullest heat communicable unto that element. Some will dissolve by this heat,

8 But whether, &c.] This paragraph was added in Second Edition. 9 is few ways effected.] "Is not in the same manner effected.”—Ed. 1646.

1 that which is concreted by exsiccation, &c.] The statements here made by our author respecting the causes of liquation and concretion, &c., are evidently derived from Aristotle, Met. lib. iv. cap. 6. See also the notes to Pseudodoxia, book i. chap. vi. p. 42.-Br.

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yet will they not suffer a liquation.] Modern chemistry shows our author to be in error in his opinion, that heat of a peculiar nature is required for the fusion of metals. The only reason why the generality of metals connot be melted by hot water is, that they require a higher temperature for their liquefaction than can be given to that fluid under ordinary circumstances. But there is an alloy of bismuth, lead, and tin, which melts at a temperature inferior to that of boiling water, (commonly called on that account fusible metal), and which accordingly melts when immersed in that fluid. Under pressure, as when heated in Papin's digester for instance, water can be raised to a much higher