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mocritus for the introduction of a vacuum, bound down, or otherwise confined, and yet strive (namely, that the same bodies could not other- with all his power to get up, the struggle is not wise comprehend and fill greater and less spaces,) the less, although ineffectual. The real state of is false. For there is clearly a folding of matter, the case (namely, whether the yielding motion by which it wraps and unwraps itself in space be, as it were, annihilated by the predominance, within certain limits, without the intervention of or there be rather a continued although an invisia vacuum. Nor is there two thousand times ble effort) will perhaps appear in the concurrence more of vacuum in air than in gold, as there of motions, although it escape our notice in their should be on this hypothesis; a fact demonstrated conflict. For instance, let an experiment be made by the very powerful energies of fluids, (which with muskets; whether a musket ball, at its ntwould otherwise float like fine dust in vacuo,) most range in a straight line, or, as it is commonly and many other proofs. The other motions direct called, point blank, strike with less force when and are directed by each other according to their projected upwards, where the motion of the blow strength, quantity, excitement, emission, or the is simple, than when projected downwards, where assistance or impediments they meet with. the motion of gravity concurs with the blow.

For instance, some armed magnets hold and The rules of such instances of predominance support iron of sixty times their own weight; so as occur, should be collected : such as the followfar does the motion of lesser congregation predo- ing; the more general the desired advantage is, ninate over that of the greater; but if the weight the stronger will be the motion; the motion of be increased, it yields. A lever of a certain connexion, for instance, which relates to the instrength will raise a given weight, and so far the tercourse of the parts of the universe, is more motion of liberty predominates over that of the powerful than that of gravity, which relates to greater congregation, but if the weight be greater, the intercourse of dense bodies only. Again, the the former motion yields. A piece of leather desire of a private good does not, in general, stretched to a certain point does not break, and prevail against that of a public one, except where so far the motion of continuity predominates over the quantities are small. Would that such were that of tension, but if the tension be greater, the case in civil matters ! the leather breaks, and the motion of continu- 49. In the twenty-fifth rank of prerogative in. ity yields. A certain quantity of water flows stances, we will place suggesting instances; such through a chink, and so far the motion of greater as suggest or point out that which is advanta congregation predominates over that of continuity, geous to mankind; for bare power and knowledge, but if the chink be smaller, it yields. If a musket in themselves, exalt, rather than enrich human be charged with ball and powdered sulphur alone, nature. We must, therefore, select from the and fire be applied, the ball is not discharged, in general store, such things as are most useful to which case the motion of greater congregation mankind. We shall have a better opportunity overcomes that of matter, but when gunpowder of discussing these when we treat of the appliis used, the motion of matter in the sulphur pre-cation to practice; besides, in the work of interclominates, being assisted by that motion and the pretation, we leave room, on every subject, for motion of avoidance in the nitre ; and so of the the human or optative chart; for it is a part of rest. For wrestling instances (which show the science to make judicious inquiries and wishes. predominance of powers, and in what manner 50. In the twenty-sixth rank of prerogative and proportion they predominate and yield) must instances, we will place the generally useful inbe searched for with active and industrious dili- stances. They are such as relate to various gence.

points, and frequently occur, sparing, by that The methods and nature of this yielding must means, considerable labour and new trials. The also be diligently examined; as, for instance, proper place for treating of instances and contriwhether the motions completely cease or exert vances, will be that in which we speak of the themselves, bu are constrained. For, in the application to practice, and the methods of expebodies with which we are acquainted, there is no riment. All that has hitherto been ascertained, real, but an apparent rest, either in the whole or and made use of, will be described in the particuin parts. This apparent rest is occasioned either lar history of each art. At present, we will subby equilibrium or the absolute predominance of join a few general examples of the instances in motions. By equilibrium, as in the scales of the question. balance, which rest if the weights be equal. By Man acts, then, upon natural bodies (besides predominance, as in perforated jars, in which the merely bringing them together or removing them) water rests, and is prevented from falling by the by seven principal methods : 1. By the exclusion predominance of the motion of connection. It of all that impedes and disturbs; 2. By compresis, however, to be observed (as we have said be- sion, extension, agitation, and the like; 3. By tore) how far the yielding motions exert them- heat and cold; 4. By detention in a suitable selves. For, if a man be held stretched out on place; 5. By checking or directing motion ; 6. the ground against his will, with arms and legs By peculiar harmonies ; 7. By a seasonable and proper alternation, series, and succession of all Any bodies, however, can easily be suspended these, or at least of some of them.

under some such vessel as we have mentioned, I. With regard to the first; common air, which which has occasioned our remarks upon the expeis always at hand, and forces its admission, as rirnent. also the rays of the heavenly bodies, create much Another advantage of the careful and hermetidisturbance. Whatever, therefore, tends to ex- cal closing of bodies is this; not only the admisclude them, may well be considered as generally sion of external air is prevented, (of which we useful. The substance and thickness of vessels have treated,) but the spirit of bodies also is prein which bodies are placed when prepared for vented from making its escape, which is an interoperations may be referred to this head. So, nal operation. For any one operating on natural also, may the accurate methods of closing vessels bodies must be certain as to their quantity, and by consolidation, or the latum sapientiæ, as the that nothing has evaporated or escaped; since chymists call it. The exclusion of air by means profound alterations take place in bodies, when of liquids at the extremity, is also very useful; art prevents the loss or escape of any portion, as, when they pour oil on wine, or the juices of whilst nature prevents their annihilation. With herbs, which, by spreading itself upon the top, regard to this circunstance, a false idea has prelike a cover, preserves them uninjured from the vailed, (which, if true, would make us despair of air. Powders, also, are serviceable, for, although preserving quantity without diminution, namely, they contain air mixed up in them, yet they ward that the spirit of bodies, and air when rarefied by a off the power of the mass of circumambient air, great degree of heat, cannot be so kept in by being which is seen in the preservation of grapes, and enclosed in any vessel, as not to escape by the other fruits, in sand and flour. Wax, honey, small pores. Men are led into this idea by compiteh, and other resinous bodies, are well used in mon experiments of a cup inverted over water, order to make the exclusion more perfect, and to with a candle or piece of lighted paper in it, by remove the air and celestial influence. We have which the water is drawn up, and of those cups sometimes made an experiment, by placing a res- which when heated draw up the flesh. For they sel or other bodies in quicksilver, the most dense think that in each experiment the rarefied air of all substances capable of being poured round escapes, and that its quantity is therefore dimi. others. Grottos and subterraneous caves are of nished, by which means the water or flesh rises great use in keeping off the effects of the sun, by the motion of connexion. This is, however, and the predatory action of air, and, in the north most incorrect. For the air is not diminished in of Germany, are used for granaries. The depo- quantity, but contracted in dimensions,* nor does siting of bodies at the bottom of water may be this motion of the rising of the water begin till also mentioned here, and I remember having heard the flame is extinguished, or the air cooled, so that of some bottles of wine being let down into a physicians place cold sponges, moistened with deep well in order to cool them, but left there by water, on the cups, in order to increase their chance, carelessness, and forgetfulness, for seve-attraction. There is, therefore, no reason why ral years, and then taken out; by which means, men should fear much from the ready escape of the wine not only escaped becoming flat or dead, air: for, although it be true that the most solid but was much more excellent in flavour; arising bodies have their pores, yet neither air nor spirit (as it appears) from a more complete mixture of readily suffers itself to be rarefied to such an its parts. But, if the case require that bodies extreme degree ; just as water will not escape by should be sunk to the bottom of water, as in a small chink. rivers, or the sea, and yet should not touch the II. With regard to the second of the seven water, nor be enclosed in sealed vessels, but sur-above mentioned methods, we must especially rounded only by air, it would be right to use that observe, that compression and similar violence vessel which has been sometimes employed under have a most powerful effect either in producing water, above ships that have sunk, in order to locomotion, and other motions of the same nature, enable the divers to remain below and breathe oc- as may be observed in engines and projectiles, or casionally by turns. It was of the following in destroying the organic body and those qualities nature. A hollow tub of metal was formed, and which consist entirely in motion, (for all life, sunk so as to have its bottom parallel with the and every description of flame and ignition are surface of the water; it thus carried down with destroyed by compression, which also injures it to the bottom of the sea all the air contained in and deranges every machine ;) or in destroying the tub. It stood upon three feet, (like a tripod,) those qualities which consist in position and a being of rather less height than a man, so that coarse difference of parts, as in colours; for the when the diver was in want of breath, he could put his head into the hollow of the tub, breathe, * Part of the air is expanded and escapes, and part is conand then continue his work. We hear that some sumed by the flame. When condensed, therefore, by the sort of boat or vessel has now been invented, ca- external atmosphere to prevent the liquid or flesh from being

cold application, it cannot offer sufficient resistance to the pable of carrying men some distance under water. forced into the glass.

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colour of a flower when whole differs from that master of violent motions than of any other it presents when bruised, and the same may be means. observed of whole and powdered amber; or in III. The third of our seven methods is referred taste, for the taste of a pear before it is ripe and to that great practical engine of nature as well as of the same pear when bruised and softened is of art, cold and heat. Here man's power limps, different, since it becomes perceptibly more sweet. as it were, with one leg. For we possess the heat But such violence is of little avail in the more of fire, which is infinitely more powerful and innoble transformations and changes of homoge- tense than that of the sun (as it reaches us) and that neous bodies, for they do not, by such means, of animals. But we want cold,* except such as acquire any constantly and permanently new we can obtain in winter, in caverns, or by surstate, but one that is transitory, and always rounding objects with snow and ice, which, perstruggling to return to its former habit and free- haps, may be compared in degree with the noondom. It would not, however, be useless to make tide heat of the sun in tropical countries, increased some more diligent experiments with regard to by the reflection of mountains and walls. For this; whether, for instance, the condensation of this degree of heat and cold can be borne for a a perfectly homogeneous body (such as air, water, short period only by animals, yet it is nothing oil, and the like) or their rarefaction, when effected compared with the heat of a burning furnace, or by violence, can become permanent, fixed, and, the corresponding degree of cold.t Every thing as it were, so changed as to become a nature. with us has a tendency to become rarefied, dry, This might at first be tried by simple perse- and wasted, and nothing to become condensed or verance, and then by means of helps and harmo- soft, except by mixtures, and, as it were, spurious nies. It might readily have been attempted, (if methods. Instances of cold, therefore, should be we had but thought of it) when we condensed searched for most diligently, such as may be found water (as was mentioned above) by hammering by exposing bodies upon buildings in a hard frost, and coinpression until it burst out. For we in subterraneous caverns, by surrounding bodies ought to have left the flattened globe untouched with snow and ice in deep places excavated for for some days, and then to have drawn off the that purpose, by letting bodies down into wells, water in order to try whether it would have im- by burying bodies in quicksilver and metals, by mediately occupied the same dimensions as it did immersing them in streams which petrify wood, before the condensation. If it had not done so, by burying them in the earth, (which the Chinese either immediately or soon afterwards, the con- are reported to do with their china, masses of densation would have appeared to have been which, made for that purpose, are said to remain rendered constant; if not, it would have appeared in the ground for forty or fifty years, and to be that a restitution took place, and that the con- transmitted to their heirs as a sort of artificial densation had been transitory. Something of the mine,) and the like. The condensations which same kind might have been tried with the glass take place in nature by means of cold should also eggs; the egg should have been sealed up sud- be investigated, that by learning their causes they denly and firmly, after a complete exhaustion of may be introduced into the arts; such as are obthe air, and should have been allowed to remain served in the exudation of marble and stones, in so for some days, and it might then have been the dew upon the panes of glass in a room towards tried whether, on opening the aperture, the air morning after a frosty night, in the formation and would be drawn in with a hissing noise, or the gathering of vapours under the earth into whether as much water would be drawn into it water, whence spring fountains, and the like. when immersed, as would have been drawn into Besides the substances which are cold to the it at first, if it had not continued sealed. For touch, there are others which have also the effect it is probable (or at least worth making the ex- of cold, and condense; they appear, however, to periment) that this might have happened, or might act only upon the bodies of animals, and scarcely happen, because perseverance has a similar effect any further. Of these we have many instances, upon bodies which are a little less homogeneous. in medicines and plasters. Some condense the A stick bent together for some time does not flesh and tangible parts, such as astringent and rebound, which is not owing to any loss of quan- inspissating medicines, others the spirits, such as tity in the wood during the time, for the same soporifics. There are two modes of condensing would occur (after a larger time) in a plate of steel, which does not evaporate. If the experi

* lent can now be abstracted by a very simple process, till ment of simple perseverance should fail, the

the degree of cold be of almost any required intersity.

# It is impossible to compare a degree of heat with a degree matter should not be given up, but other means of cold, without the assumption of some arbitrary test, to should be employed. For it would be no small which the degrees are to be referred. In the nest sentence

appears to have taken the power of animal life to supadvantage, if bodies could be en lued with fixed port heat or cold as the test, and then the comparison can only iind constant natures by violence. Air could be between the degree of heat or of cold that will preduce then be converted into water by condensation, with other similar effects; for man is more the degree of heat from a certain degree of cold.

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the spirits, by soporifics or provocatives to sleep; for from their investigation, unless the discovery the one by calming the motion, the other by of forms and conformation be attained. With expelling the spirit. The violet, dried roses, let-regard to animal bodies, it is not to be questioned tuces, and other benign or mild remedies, by their that there are many internal and external medifriendly and gently cooling vapours, invite the cines which condense by harmony, as we have spirits to unite, and restrain their violent and per- before observed, but this action is rare in inaniturbed motion. Rose-water, for instance, applied mate bodies. Written accounts, as well as reto the nostrils in fainting fits, causes the resolved port, have certainly spoken of a tree in one of the and relaxed spirits to recover themselves, and, as Tercera or Canary Islands (for I do not exactly it were, cherishes them. But opiates, and the recollect which) that drips perpetually, so as to like, banish the spirits by their malignant and supply the inhabitants, in some degree, with hostile quality. If they be applied, therefore, exter- water; and Paracelsus says, that the herb called nally, the spirits immediately quit the part, and no ros solis is filled with dew at noon, whilst the sun longer readily flow into it; but if they be taken gives out its greatest heat, and all other herbs internally, their vapour, mounting to the head, around it are dry. We treat both these accounts expels, in all directions, the spirits contained in as fables; they would, however, if true, be of the ventricles of the brain, and since these spirits the most important service, and most worthy of retreat, but cannot escape, they consequently examination. As to the honey-dew, resembling meet and are condensed, and are sometimes com- manna, which is found in May on the leaves of pletely extinguished and suffocated; although the the oak, we are of opinion that it is not condensed same opiates, when taken in moderation, by a by any harmony or peculiarity of the oak leaf, but secondary accident, (the condensation which suc- that whilst it falls equally upon other leaves, it ceeds their union,) strengthen the spirits, render is retained and continues on those of the oak, bethem more robust, and check their useless and cause their texture is closer, and not so porous as inflammatory motion, by which means they con- that of most of the other leaves. * tribute not a little to the cure of

and the With regard to heat, man possesses abundant prolongation of life.

means and power, but his observation and inquiry The preparations of bodies, also, for the recep- are defective in some respects, and those of the tion of cold, should not be omitted, such as that greatest importance, notwithstanding the boasting water a little warmed is more easily frozen than of quacks. For the effects of intense heat are that which is quite cold, and the like.

examined and observed, whilst those of a more Moreover, since nature supplies cold so sparing- gentle degree of heat, being of the most frequent ly, we must act like the apothecaries, who, when occurrence in the paths of nature, are, on that very they cannot obtain any simple ingredient, take account, least known. We see, therefore, the a succedaneum, or quid pro quo, as they term it, furnaces, which are most esteemed, employed in such as aloes for xylobalsamum, cassia for cinna- increasing the spirits of bodies to a great extent,

In the same manner we should look dili- as in the strong acids, and some chymical oils ; gently about us, to ascertain whether there may whilst the tangible parts are hardened, and, when be any substitutes for cold, that is to say, in what the volatile part has escaped, become sometimes other manner condensation can be effected, which fixed; the homogeneous parts are separated, and is the peculiar operation of cold. Such conden- the heterogeneous incorporated and agglomerated sations appear hitherto to be of four kinds only. in a coarse lump; and (what is chiefly worthy of 1. By simple compression, which is of little avail remark) the junction of compound bodies, and towards permanent condensation, on account of the more delicate conformations are destroyed and the elasticity of substances, but may still how- confounded. But the operation of a less violent ever be of some assistance. 2. By the contrac- heat should be tried and investigated, by which tion of the coarser, after the escape or departure more delicate mixtures and regular conformations of the finer parts of a given body; as is exempli- may be produced and elicited, according to the fied in induration by fire, and the repeated heating example of nature, and in imitation of the effect and extinguishing of metals, and the like. 3. By of the sun, which we have alluded to in the he cohesion of the most solid homogeneous parts aphorism on the instances of alliance. For the of a given body, which were previously separated, works of nature are carried on in inuch smaller and mixed with others less solid, as in the return ' portions, and in more delicate and varied positions of sublimated mercury to its simple state, in than those of fire, as we now employ it. But which it occupies much less space than it did in man will then appear to have really augmented powder, and the same may be observed of the his power, when the works of nature can be cleansing of all metals from their dross. 4. By imitated in specie, perfected in power, and varied harmony or the application of substances which in quantity ; to which should be added the accecondense by some latent power. These harmo- leration in point of time. Rust, for instance, is nies are as yet but rarely observed, at which we

* It may often be observed on the leaves of the lime and cannot be surprised, since there is little to hope other trees.




the result of a long process, but crocus Martis is / wasted by the lapse of ages. The incorporations obtained immediately; and the same may be ob- and nixtures, which are hurried by fire, are very served of natural verdigris and ceruse. Crystal | inferior to those obtained by continuance; and is formed slowly, whilst glass is blown immedi- the various conformations assumed by bodies left ately: stones increase slowly, whilst bricks are to themselves, such as mouldiness, &c., are put a baked immediately, &c. In the mean time (with stop to by fire or a strong heat. It is not, in the regard to our present subject) every different spe- mean time, unimportant to remark, that there is a cies of heat should, with its peculiar effects, be certain degree of violence in the motion of bodies diligently collected and inquired into; that of entirely confined. For the confinement impedes the heavenly bodies, whether their rays be di- the proper motion of the body. Continuance in rect, reflected, or refracted, or condensed by a an open vessel, therefore, is useful for separations, burning-glass; that of lightning, flame, and ignit- and in one hermetically sealed for mixtures, that ed charcoal ; that of fire of different materials, in a vessel partly closed, but admitting the air for either open or confined, straitened or overflowing, putrefaction. But instances of the operation and qualified by the different forms of the furnaces, effect of continuance must be collected diligently excited by the bellows, or quiescent, removed from every quarter. to a greater or less distance, or passing through V. The direction of motion (which is the fifth different media; moist heats, such as the bal- method of action) is of no small use. We adop! neum Mariæ, and the dunghill; the external and this term when speaking of a body, which, meetinternal heat of animals; dry heats, such as the ing with another, either arrests, repels, allows, or heat of ashes, lime, warm sand; in short, the directs its original motion. This is the case nature of every kind of heat, and its degrees. principally in the figure and position of vessels.

We should, however, particularly attend to the An upright cone, for instance, promotes the coninvestigation and discovery of the effects and densation of vapour in alembics, but, when operations of heat, when made to approach and reversed, as in inverted vessels, it assists the reretire by degrees, regularly, periodically, and by fining of sugar. Sometimes a curved form or proper intervals of space and time. For this one alternately contracted and dilated is required. systematical inequality is in truth the daughter Strainers may be ranged under this head, where of heaven and mother of generation, nor can any the opposed body opens a way for one portion of great result be expected from a vehement, preci- another substance and impedes the rest. Nor is pitate, or desultory heat. For this is not only this process, or any other direction of motion, inost evident in vegetables, but in the wombs of carried on externally only, but sometimes by one animals, also, there arises a great inequality of body within another. Thus, pebbles are thrown heat, from the motion, sleep, food, and passions into water to collect the muddy particles, and of the female. The same inequality prevails in syrups are refined by the white of an egg, which those subterraneous beds where metals and fossils glues the grosser particles together so as to faciliare perpetually forming, which renders yet more tate their removal. Telesius, indeed, rashly and remarkable the ignorance of some of the reformed ignorantly enough attributes the formation of anialchymists, who imagined they could attain mals to this cause, by means of the channels and their object by the equable heat of lamps, or the folds of the womb. He ought to have observed like, burning uniformly. Let this susfice con- a similar formation of the young in eggs, which cerning the operation and effects of heat; nor is have no wrinkles or inequalities. One may obit time for us to investigate them thoroughly be- serve a real result of this direction of motion in fore the forms and conformations of bodies have casting and modelling. been further examined and brought to light. VI. The effects produced by harmony and When we liave determined upon our models, aversion (which is the sixth method) are frewe may seek, apply, and arrange onr instru- quently buried in obscurity. For these occult ments.

and specific properties, (as they are termed,) the IV. The fourth mode of action is by continu- sympathies and antipathies are for the most part ance, the very steward and almoner, as it were, but a corruption of philosophy. . Nor can we of nature. We apply the term continuance to form any great expectation of the discovery of the abandonment of a body to itself for an ob- the harmony which exists between natural objects, servable time, guarded and protected in the before that of their forms and simple conformamean while from all external force. For the tions, for it is nothing more than the symmetry internal motion then commences to betray and between these forms and conformations. exert itself when the external and adventitious is The greater and more universal species of har

The effects of time, however, are far mony are not, however, so wholly obscure, and more delicate than those of fire. Wine, for with them, therefore, we must commence. The Instance, cannot be clarified by fire as it is by first and principal distinction between them is continuance. Nor are the ashes produced by this; that some bodies differ considerably in the combustion so fine as the particles dissolved or abundance and rarity of their substance, but cor


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