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consequence is immaterial. For I suppose that there are none so ignorant as to imagine that pneumatic and volatile vapours, which fly off from heavy bodies, lie hid in the pores of the same bodies, and are not of the same matter with the ponderous body, but are separated from the ponderous part, when the water is, as it were, entirely consumed, and evaporates into nothing. A live coal, if placed in the scale of a balance and left till it becomes a cinder, will be found to be much lighter. Metals themselves are changed in a wonderful degree in weight by the evolutions of their smoke. The same matter, therefore, is tangible and has weight, and is yet pneumatic, and can be divested of weight.

History.

But if the vapour is inflamed in the part verging a little obliquely from the mouth of the phial, the inflammation becomes pensile in the air, undulating or winding after the appearance of vapour, and would doubtless attend it longer if the vapour remained together and did not confound itself with the air. And the body itself of spirit of wine, if no remarkable vapour goes before, the fire being applied to it and kept to it a little while is changed into the flame, and it expands with so much the greater ease and swiftness, as the spirit is more widely diffused and occupies a less altitude. But if the spirit of wine is put in the hollow of the palm of the hand, and a lighted candle between the fingers is placed near the palm of the hand, (as boys are wont to play with powder of resin,) and the spirit is gently moved forward, and straight forward, not upward; the body itself burns in the air, and when burning sometimes descends in a right direction, sometimes unfolds a little cloud flying in the air, which nevertheless verges itself to descent; sometimes when set on fire it cleaves burning, to the roof or sides, or floor of the room, and gradually becomes extinct.

The mode of the process of oil is this. If oil be poured into a common glass phial and placed upon the fire, it will boil much more slowly, and will require a greater heat than water. And at first some drops and small grains appear scattered through the body of the oil, ascending with a creaking sound the bubbles in the mean time do not play on the surface, as is the case with water, Vinegar, verjuice, wine, milk, and other simple nor does the body rise whole, and in general no liquors (I speak of vegetable and animal substeam flies off, but a little afterward the whole stances, for of minerals I will treat by themselves) body is inflated and dilated in a remarkable pro- | have their modes of expansion, and some remarkportion, as if rising in a twofold degree. Then, able differences attending them, which it would indeed, a very copious and dense steam arises: be out of place here to enumerate: but they are if a fire be applied to the steam, even good way in those natures which we have remarked in the above the mouth of the phial, the steam forthwith processes of water, oil, and spirit of wine; namely, produces a flame, and descends immediately to in the degree of heat; and mode of expansion the mouth of the phial, and there fixes itself and which is threefold, either in the whole body or in continues burning. But if the oil is heated to a froth, or in rather large bubbles; for fat bodies, greater degree, the steam burning to the last, out of unripe juice, as generally ascend in greater of the phial, without any flame or ignited body bubbles, of dried sap, as vinegar, in less. A colbeing applied, completely inflames itself, and lection of spirit moreover differs in its site. For takes the expansion of the flame. in the boiling of wine, the bubbles begin to collect themselves about the middle, in vinegar about the sides and it is the same in ripe and strong wine, and again in vapid or stale, when they are infused. But all liquors, even oil itself, before they begin to boil, cast up a few and thin half bubbles about the sides of the vessel. And all liquors boil and are consumed quicker in a small than in a great quantity.

Caution.

See that the mouth of the phial is rather narrow, that the phial may confine the fumes, lest by their largely and immediately mixing with the air, they lose their inflammable nature.

History.

The method of process of spirit of wine is this: it is excited by much less heat, and brings itself to expand sooner and more than water. It boils up with great bubbles without froth, and even with the raising of its whole body, but the vapour, whilst it is collected, will on the application of fire produce fire, at a good distance from the mouth of the glass, not so bright (but at least as compact) as oil, but thin and scant of a blue colour, and almost transparent. But being inflamed, it is borne to the mouth of the glass, where is a supply of more copious fuel, as it is also with oil. VOL. II.-72

Caution.

I consider that compounded liquors are not proper to the history of the expansion and union of matter through the medium of fire, because they disturb and confuse the ratios of simple expansion and coition by their separations and mixtures. I leave them, therefore, for the proper history of the separation and mixture of matter.

History

Spirit of wine, put in an experiment with that elastic cap, (which I described when speaking of water,) obtains this sort of expansion. I find

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tracted from heat and cold in those bodies of wind which physicians use for attraction. For, these warmed over the fire, and then applied immediately to the body, draw the skin, the air contracting itself and gradually recovering itself. And this it does of itself, although the hemp may not have been put on and heated, which is used to produce a more powerful attraction. Moreover, if a cold sponge be applied outside over the blister, the air contracts itself so much the more by virtue of the cold, and the attraction becomes more determined.

I have put a silver saltcellar of the usual belltower form, in a bath or goblet filled with water, bearing the air depressed with itself to the bottom of the vessel. I then put two or three live coals in the little hollow space in which the salt is placed when applied to its ordinary use, and raised a flame by blowing. Very soon after, the air, rarefied by the heat, and impatient of its former orbit, lifted up the bottom of the saltcellar on one side, and ascended in bubbles. Hero describes an altar so constructed as that, if you laid a holocaust upon it and set it on fire, suddenly water would fall to extinguish the fire. This might be accomplished by air being received under the altar in a hollow space closed up, and with no other way of exit, (when the air was extended by the fire,) but where it might force out the water prepared for this purpose in the channel. There were lately in this country some Hollanders who had invented a musical instrument, which, on being struck by the rays of the sun, gave out a certain harmony. This was very probably owing to the extension of the heated air, which could produce the motion of the instrument, since it is certain that air acted upon by the contact of the very slightest heat, immediately begets expansion.

that a weight of six pennyweights, consumed | clearly see that air itself is expanded and conand dissolved into vapour, filled and fully inflated a great bladder which could contain eight pints; which bladder was greater by sixteen times than that which I used in the case of water, which received only half a pint. But, in the experiment of the water, there was a consumption of the weight of only two pennyweights, which is only the third part of six pennyweights. The ratios being thus calculated, the expansion of the vapour of spirit of wine bears a fivefold ratio and more, to the expansion of the vapour of water. And that very great expansion did not keep the body, on the removal of the vessel from the fire, from hastening to recover itself, the bladder forthwith becoming red and remarkably contracted. And, from this experiment, I began to estimate the expansion of the body of flame on probable, though not indisputable conjecture. For, since the vapour of spirit of wine is so inflammable, and approaches so near the nature of fire, I considered that the ratios of spirit of wine, compared with fire, agreed with the ratios of the vapour of water compared with air. For, we may suppose that the ratios of perfect and fixed bodies (as of air and fire) are in harmony with those of the elements, or imperfect and moving bodies, (as of vapours.) And it will follow from this, that fire exceeds air by five degrees, in the rarity or expansion of matter. For such is the excess of their respective vapours, as was before said. For, the fire itself may bear the ratio of one and a half to the proper vapour, not the impure, but the highly prepared vapour; as I have laid it down, also that air can have the same ratio to the vapour of water highly prepared. And these experiments do not disagree materially with what we may frequently observe. For, if you blow out a lighted wax candle, and mark the dimension of the smoky thread which ascends, (in the lowest part before it is dispersed,) and place the candle near the fire, and again look at that portion of the fire which first reaches it, you will not imagine that it exceeds more than double the magnitude of the smoke. If you mark with accuracy the dimension of gunpowder, or, for greater certainty, measure it in a little box, and again take the dimension of its flame, after it has been lit, you will readily grant that the flame exceeds the body, as far as it can be told at first sight, a thousand degrees. And, from what has been before laid down, there should be a considerable proportion of fire according to the nitre. But this I will explain more perfectly in my observations upon this history. We very

But, in order to come at a more accurate knowledge of the expansion of the air let into that elastic bladder, I took an empty glass, (I mean, filled only with air,) and placed upon the bladder, the cap of which I before treated. But when the phial was placed over the fire, the air extended itself more quickly and with less heat than water or spirit of wine, but with not a very ample expansion. For it bore this proportion. If the bladder held less by six ounces than the phial itself, the air completely filled and inflated it; it did not ascend easily on greater expansion; and no visible body proceeded out of it, after making a little hole in the top of the bladder, until it was inflated. A. T. R.

DESCRIPTION

OF THE

INTELLECTUAL GLOBE.

CHAPTER I.

arbitrarily applied, so as to form a certain likeness of some individual, it is the work of imagination; which, restrained by no law or necessity Division general of Human Learning into Histo- of nature or of matter, can unite things which in ry, Poesy, Philosophy, according to the three nature are most discordant, and divide those Faculties of the Mind, Memory, Imagination, which never exist in separation, so as however Reason; showing that the same Division holds this is still confined to such original parts of the also in Matters Theological; since the Vessel, individuals. For there is no imagination, not namely, Human Intellect, is the same, though the even a dream, of objects which have not in some Matter contained, and the Mode of its Entrance, shape presented themselves to the senses. Again, be different.

We adopt that division of human learning which is correlative to the three faculties of the intellect. We therefore set down its parts as three, History, Poesy, Philosophy:-history has reference to memory, poesy to imagination, philosophy to reason. By poesy in this place, we mean nothing else but feigned history. History is, properly, the history of individual facts, the impressions of which are the earliest and most ancient guests of the human mind, and as it were the primitive matter of the sciences. To deal with these individuals and that matter forms the mind's habitual employment, and occasionally, its amusement. For all science is the labour and handicraft of the mind; poetry can only be considered its recreation. In philosophy the mind is enslaved to things, in poesy it is let loose from the bondage of things, and breaks forth illimitably, and creates at will. And any one may easily comprehend that this is so, who shall seek the source of things intellectual even on the simplest principles, and with the most crass apprehension. For the images of things individual are admitted into the sense and fixed in the memory. They pass into the memory, as it were, whole, in the same manner as they present themselves. These the mind recals and retraces; and, which is its proper business, puts together and decomposes their parts. Now, individuals severally have something in common one with another, and again something diverse and complex. Composition and division takes place either at the will of the mind itself, or agreeably to what is found in nature. If it is done at the mere volition of the mind, and such parts of things are

if the same sections of objects be joined or divided according to the real evidence of things, and as they actually present themselves in nature, or at least as they are observed to present themselves according to the general apprehension of mankind, this is the office of reason; and all such adjustment is ascribed to reason.

Whence it clearly appears that from these three sources there arise the three several streams of history, poesy, and philosophy, and that there cannot be other or more branches than these. For under the name of philosophy we comprehend all the arts and sciences, and whatever in short can, from the presentment of the several objects of nature, be by the mind collected and arranged into general notions. Nor do we think that there is occasion, in consideration of the extent of the subject, for any other division of learning than that which we have stated above. For though the responses of a divine oracle and of the senses are different, no doubt, both in the matter and the mode by which it finds access to the mind; yet the spirit of man which receives both is one and the same, just as different liquors passing through differents apertures are received into one and the same vessel. Wherefore we assert that history. itself either consists of sacred history, or of divine precepts and doctrines, which are, so to speak, an everyday philosophy. And that part which seems to fall without this division, prophecy, is itself a species of history, with the prerogative of deity stamped upon it of making all times one duration, so that the narrative may anticipate the fact; thus also the mode of promulgating vaticination by vision, or the heavenly doctrines by parables, partakes of the nature of poetry.

571

and constrained.

CHAPTER II.

new face of things, or second universe. Wherefore natural history of either the liberty of nature or its errors into bonds. Now, if it be unpleasing

A partition of History into Natural and Civil, Ec- to any one that the arts should be called the clesiastical, Literary, and Particular, included bonds of nature, since they are rather to be conin Civil History. A division of Natural Histo-sidered its deliverers and champions, since they ry into the History of Generations, Præter-gene- make nature, in some instances, mistress of her rations, and Arts; according to the three states object, by reducing obstacles into her order. We of Nature, namely, Nature in course, varying, regard little such delicacies and elegancies of language. We only mean to signify this, that nature, by means of arts, is placed by compulsion under a necessity of doing that which without arts would not have been done, whether that be denominated force and bonds, or assistance, and consummating skill. We shall therefore divide natural history into the history of generations, the history of preter-generations, and the history of arts, which we are accustomed to call mechanical and experimental history. And we willingly place the history of arts among the species of natural history, because there has obtained a now inveterate mode of speaking and notion, as if art were something different from nature, so that things artificial ought to be discriminated from things natural, as if wholly and generically different; whence arises this evil, that most writers of natural history think they have accomplished their task if they have achieved a history of animals, plants, or minerals, omitting the experiments of mechanics, which are of by far the greatest consequence to philosophy; and there has insinuated itself into mens' minds a still subtler error, namely, this, that art is conceived to be a sort of addition to nature, the proper effect of which is to perfect what nature has begun, or to correct her where she has deviated; but by no means to work radical changes in her, and shake her at the roots, which has been a source of great despondency in the attempts of men. Whereas, on the contrary, that ought to be sunk deep that things artificial do not differ from natural in form or essence but in efficients only; that in reality man has no power over nature, except that of motion, namely, to apply or to remove natural bodies; but nature performs all the rest within herself. Wherefore, when there is granted a proper application or removal of natural bodies, men and art can do all; when not granted, nothing. Again, provided that due admission and removal takes place in order to some effect, it matters not whether it be done by man or by art, or by nature without man. Nor is the one more potent than the other; so, if any one by sprinkling water create the apparition of a rainbow upon a wall, he does not find nature less obedient than when the same takes place in the air on humid clouds. Again, when gold is found pure in veins, where nature has performed exactly the same office to herself, as if pure gold was extracted by means of the smelting pot and ministry of man. Sometimes, too, a ministry of this kind

HISTORY is either natural or civil. In natural history we recount the events and doings of nature; in civil, of men. Things divine no doubt have a conspicuous share in both, but chiefly in human, so as to constitute a branch of their own in history, which we are accustomed to call sacred or ecclesiastical. We shall therefore assign that branch to the province of civil history: and we shall first speak of natural history. There is extant no natural history of things individual. Not that we would lay down the false position that history ought to be engrossed with describing individuals, which are limited in time and place. For in that view it is proper there should be none; since, however, there is a general resemblance of natural objects, so that if you know one you know all, it were superfluous and interminable to speak of individuals. Thus, if in any case that indistinguishable general resemblance be wanting, natural history admits individuals those, that is, of which there is not a number or family. For a history of the sun, the moon, the earth, and the like, which are unique in their species, is most properly written, and no less of those which conspicuously vary from their species and are monstrous; since the description and the knowledge of the species neither sufficiently nor competently supplies the want of it. Wherefore natural history does not exclude these two classes of individuals, but is in by far the largest part of it, as we have already stated, employed about species. But we attempt a partition of natural history, derived from the tendency and condition of nature herself, which is found placed in three several states, and subject as it were, to three modes of government. For nature is either free, spontaneously diffusing and developing itself in its wonted course, that is, when nature depends upon itself, in no way obstructed and subdued, as in the heavens, animals, plants, and all the natural productions; or, again, it is evidently torn down and precipitated from its proper state by the pravity and erratic tendency of obdurate and resisting matter, or by violence of obstacles, as is the case in the care of monsters and unnatural productions; or, finally, it is coerced by the art and industry of man, fashioned, altered, and as it were made anew, as in things artificial. For in things artificial nature seems, as it were, new made, and there is seen a

is, by the laws of the universe, committed to other animals. For honey is not the less an artificial production, which is produced through the medium of the industry of the bee, than sugar which is produced by that of man; and in manna, which is a similar composition, nature is content with her own chymistry. Since, then, nature is one and the same thing, and its power åll-pervading and never at war with itself, these three things ought to be understood as equally subordinate only to nature; the course of nature, the eccentricity of nature, and art or man added to the universe, and therefore it is fitting that all these things should be interwoven in one continuous series of narrations, which Caius Pliny in a great manner attempted, who embraced natural history with a comprehensiveness of plan suitable to its dignity, but having embraced it, treated it most meagerly. Let this, then, be the first division of natural history.

either the great names of the ancients, or the great tomes of the moderns, startle the mental vision of any one; and let him not think that our complaint is the less just. We are well aware that there is extant a natural history, voluminous in its bulk, entertaining from its variety, often interesting, elaborate even to scrupulosity. But if one shall extract from it accounts derived from fable and antiquity, the quotations and testimonies of authors, the empty questions and controversies, and, finally, that part of it which is mere words and rhetorical ornament, (which is better adapted to disquisition and the talk of literary nights than to establish philosophy,) this great appearance of substance subsides to nothing. Thus there seems to have been desiderated and collected by some men, in this instance, rather a Thesaurus for the allusions of eloquence, than a solid and authentic narrative of facts. Besides, it seems to no great purpose to recount or know the wonderful varieties of flowers of the iris or the tulip, of shells, or dogs, or hawks. For these are nothing but the sport or wantonness of nature, and approach nearly the nature of individuals. By which means men acquire exquisite minuteness of knowledge in the objects, but meager and even useless information as respects the purposes, of science. Yet, these are the things of which the common natural history makes such an ostentatious display. Now, though natural history has, on the BUT Natural History, threefold in its subject, one hand, degenerated into foreign, and, on the (as we have stated,) is twofold in its use. For other, indulged in superfluous inquiries, yet asit is employed either for the purpose of furnishing suredly great and valuable parts of it have either. knowledge of those facts which are recorded by been entirely passed over, or carelessly and lightly the history, or as the primitive matter of philoso- handled. And in the whole scope of its investiphy. But, if the noblest end of natural history gations and its accumulations, it is not by any is this, that it is, so to speak, the stuff and Hyle of means found adapted and qualified to attain the just and legitimate induction, and draws enough end of which we speak, namely, to found philosofrom the sense to instruct the intellect. For that phy. This will appear best in its particular other sort of history, which either delights by the branches, and by a comparison of that history, charm of the narration, or pleases by its sub-whose descriptions we shall presently submit to serviency to immediate experiments, and which the eyes of man, with that which now obtains.

CHAPTER III.

A Partition of Natural History according to its Use
and End, showing that by far the noblest End of
Natural History is its Ministration in the first
Instance to found Philosophy; and that such a
History-a History modelled in Order to such
End, is wanted.

is in request either in respect of such pleasure or such profit, is of a cast inferior, and in its nature meaner, in comparison with that of which it is the nature and the quality to serve as an appropriate preparation to found philosophy. For that is the true natural history which is established as an immovable and eternal foundation for true and practical philosophy; which affords the first genial kindling to the pure light of nature, wherein all phantasms vanish; and of which the genius, neglected and unappeased by fit offerings, has, in an evil hour, sent among us those legions of spectres and worlds of shadows, which we see hovering over all the expanse of the philosophies, along with great and lamentable dearth of useful works. Now, we assert and explicitly testify, that a natural history, such as it ought to be in order to this end, is not possessed, but ought to be placed among histories wanting. And let not

CHAPTER IV.

The Treatise begins by stating what the History wanted ought to be; namely, a Natural History, as a Foundation for Philosophy. To unfold this more clearly, there is first exhibited a Scheme of the History of Generations. Of this the Parts are set down as five: The first, the History of the Heavenly Bodies; the second, of Meteors; the third, of Earth and Sea; the fourth, of the greater Colleges of Things, that is, of Elements or Masses; the fifth, of the smaller Colleges or Species. The History of primitive Virtues is reserved, till the exposition of the first Division, namely, of Generations, Preter-generations, and Arts, is completed. As we think it concerns our honour not to leave others the execution of the history which we

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