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pelling force, is many degrees swifter than the motion of gravity, which makes the resistance, so that the prevailing motion is performed before the opposite motion begins, whilst at first there was a kind of neutrality, or want of resistance. And hence, in all projectiles, it is not so much the strong as the sharp and quick stroke, or percussion, that carries the body farthest. Nor was it possible that a small quantity of spirit in animals, especially in those so bulky as the elephant, or the whale, should move and manage so great a mass of matter, but for the velocity of the motion of the spirit, and the inability of the corporeal mass to resist.

And this is one of the principal foundations of the magical instances, which we shall soon consider *, wherein a small quantity of matter overpowers and subdues a much greater; that is, where there may be a pre-occupation, or anticipation of motions, by the velocity of one, before another is ready t.

Lastly, this business of anticipation and subsequence should be observed in all natural actions. Thus in the infusion of rhubarb, the purgative virtue is drawn out first, and the astrin

*See below, Aph. 51.

+ This deserves to be carefully considered and remembered; for many extraordinary operations and cases of practice, depend upon it.

gent virtue afterwards. And something of the like kind we have found upon infusing violets in vinegart, where the sweet and delicate odour of the flowers is first received, and afterwards the more earthy part, which confounds the odour; therefore, if violets be infused for a whole day, their smell is obtained much fainter than if they were infused only for a quarter of an hour, and then taken out. And because violets contain but little odoriferous spirit, if fresh ones be infused in the same liquor, every quarter of an hour, for six times, the tincture, or infusion, will become so rich in the space of an hour and a half, as to continue, for a whole year, of an exceeding grateful odour, not inferior to the flowers themselves. But it must be observed, that the odour does not come to collect its full strength, till a month after the infusion is made. And the business of distillation affords numerous remarkable examples to the same purpose.

47. In the twenty-third place, among prero, gative instances, come instances of quantity, which we also call the doses of nature‡, borrowing the expression from medicine. These are such instances as measure virtues by the quantities of bodies, and indicate what the quantity of a body contributes to the quantity of virtue.

* See the Sylva Sylvarum, under the article Infusion. See the last cited. See above, Aph. 44.

And, first, there are certain virtues subsisting only in a cosmical quantity; that is, such a quantity as has a consent with the configuration and structure of the universe. Thus the whole body of the earth, unmoved suppose in its whole, does not fall downwards, though its parts do; the waters ebb and flow in the sea, but not in rivers, unless where they communicate with the sea; and almost all particular virtues operate in proportion, as the body is bigger or less. Large collections of water do not easily corrupt, as small ones do. New wines and drinks ripen quicker, or become sooner potable, when contained in small vessels, than when in large ones. If a plant be added to a large proportion of liquor, it makes an infusion rather than a tinc→ ture; but if to a less, it makes a tincture rather than an infusion. So, with regard to the human body, bathing is one thing, but sprinkling another. And thus the finest dews never fall in the air, but are dissipated and incorporated with it. And we see in breathing upon polished gems, that the small quantity of moisture thus left upon their surface, is presently licked up by the air, as a light cloud, or mist, is dissipated by the wind. Again, a piece of loadstone will not attract so much iron as the whole loadstone would do.

There are also virtues, wherein smallness of quantity has the greatest effect, as a sharp point penetrates easier than a blunt one, and as the angular point of a diamond cuts glass; with other examples of the like kind.

But we are not here to dwell upon indefinites, but should enquire into the proportions of the quantity of a body, with regard to the measure of its virtue, for one might easily imagine, that the proportions of quantity corresponded to the proportions of virtue, as that a leaden bullet of two ounces should fall twice as swift as another of one ounce, which is absolutely false. Nor do the same, but very different proportions obtain in all kinds of virtues; and, therefore, these measures must be derived from experiments, and things themselves, and not from probabilities or conjectures.

Lastly, in every natural enquiry, the quantity of the body required to produce any effect must be set down, as the dose, and the cautions, with regard to quantity, either in excess or defect, continually interspersed.

48. In the twenty-fourth place come instances of reluctance, which we also call by the name of prevailing instances; that is, such as shew the predominancy, or subjection of virtues to one another, or which of them is the stronger and

prevails, and which the weaker and submits; for the motions and struggles of bodies are no less compounded, recompounded, and complicate, than bodies themselves. We will, therefore, first lay down the principal species of motions, or active virtues, that their comparison, in point of strength, may be the clearer; and thence the instances of reluctance and prevalence be the better known and designed.

The first motion may be the motion of resistance in matter, or the motion that resides in all the parts thereof, and will not suffer it to be any way annihilated; so that no force of fire, no weight or depression, no violence, no length of time, or continuance of duration, can ever possibly reduce any the least particle of matter to nothing, but it will still continue something; possess a certain space, and, to whatever necessity it be reduced, free itself, either by changing its form or place, or, if it cannot do that, it will continue as it was, so that the time shall never come when it is nothing, or has no existence. And of this motion we need produce no examples, because it is universal, or exists in all bodies*.

Let the second motion be that we term motion of connection, whereby bodies suffer not

* See the Author's History of Condensation and Rarifaction.

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