Imágenes de páginas
[ocr errors]

but if there be not a sufficient quantity to follow, the water then falls in round drops, which is the figure that best supports it against discontinuation; and at the very instant when the thread of water ends, and the falling in drops begins, the water recoils upwards to avoid being discontinued. So in metals, which are fluid upon fusion, though a little tenacious, some of the mettled mass frequently springs up in drops, and sticks in that form to the sides of the crucible. There is a like instance in the lookingglasses, commonly made of spittle by children, in a loop of rush or whalebone, where we find a consistent pellicule of water. But this is observed to much better advantage in that other diversion of children, when they take strong soapy water, and blow in it with a pipe, so as to raise the water into a tower or castle of bubbles, whilst by the interposition of the air, the soapy water becomes consistent to that degree as to be thrown a considerable distance without breaking. This also appears to advantage in froth and snow, which put on such a con-✨ sistency, that they may be almost cut with a knife, though they are but bodies formed of air.. and water, both of them fluid. These several instances seem clearly to intimate that fluidity and consistency are no more than vulgar notions relative to the human sense, and that all bodies

have a real appetite to avoid discontinuation, though in homogeneous bodies, such as fluids are, it is but weak and feeble, whilst in those compounded of heterogeneous matters, it proves more strong and powerful, because the application of what is heterogeneous binds bodies up, but the entrance of what is homogeneous relaxes and dissolves them *.

As a farther example; if the nature sought were attraction, or the appetite of approach in bodies, a most remarkable glaring instance, as to the discovery of the form, is the loadstone. The contrary of an attractive nature is an unat tractive nature, though in a similar substance; as in iron, which does not attract iron; nor does lead attract lead, nor wood attract wood, nor water attract water. But the loadstone armed with iron, or rather the iron of an armed loadstone, is a clandestine instance; for here it happens, that an armed loadstone does not, at a certain distance, attract iron stronger than an unarmed loadstone; but if the iron be moved so near as to touch the iron of the armed loadstone, then the armed loadstone will support a much greater weight of iron, than the naked and unarmed loadstone, by reason of the

Consider the instances derivable from chemistry, and the doctrine of menstruums.

[ocr errors]

similitude of substance betwixt iron and iron, which operation was altogether clandestine and secret, or concealed in the iron before the loadstone was applied. Whence it is manifest, that the form of attraction is a thing that is vivid and strong in the loadstone, but weak and latent in iron.

After the same manner, it is observed, that headless arrows of wood, being fired out of a gun, will penetrate farther into wood, or the sides of a ship, than the same arrow headed or pointed with iron, by reason of the similitude of substance betwixt wood and wood*, though this before lay concealed in the wood.

Again; though air does not manifestly attract air, nor water manifestly attract water, in a state of entireness, yet one bubble approaching another makes it easier dissolve, than if the other bubble were away, by reason of the appetite of conjunction between water and water, and between air and air.

And this kind of clandestine instances, which, as we before observed, have a noble use, are most remarkable in the small and subtile parts of bodies, because the greater masses of things follow the more general and universal forms †.

*Is the fact certain? See the Sylva Sylvarum.

We have here a remarkable opening into the doctrine of attraction. See Sir Isaac Newton's Principia and Optics, passim.

26. In the fifth place, come constituent or collective instances; that is, such as constitute one species of a nature enquired after, in the way of a lesser form. For, as genuine forms, which are always convertible with the natures sought*, lie deep, and are not easily found; the design itself and the weakness of the understanding require that partial forms, which are collective of certain packets of instances (though by no means of all) into some common notion, should not be neglected, but carefully observed; for whatever collects and unites natures, though it be but imperfectly, paves the way to the discovery of forms. And therefore those instances which are useful to this purpose, have a considerable power and a prerogative nature.

But great caution must here be employed lest, the understanding, after having found many of these particular or partial forms, and hence made arrangements or divisions of the nature sought after, should wholly rest in them, and not apply itself to the legitimate discovery of the great form, but presuppose nature to be manifold and divided, as it were, in the root, and therefore disdain and reject all farther uniting of her, as a matter of needless subtility, and tending to mere abstract speculation.

For example, let the nature sought be

* See Part II. Aph. 4.

memory, or the means of exciting and helping the memory; the constituent instances will here be, first, order, or distribution, and places for artificial memory. Order, or distribution, manifestly assists the memory; and places for artificial memory, may either be places in a proper sense, as a door, a window, a corner, &c. or familiar and known persons; or any other things at pleasure; provided they be placed in a certain order; as animals, plants, words, letters, characters, historical personages, &c. though some of these are more, and some less fit for the purpose. But such kind of places greatly help the memory, and raise it far above its natural powers. Again; verse is easier learnt and remembered than prose.

And this collection, or packet, of the three abovementioned instances, viz. order, artificial place, and verse, constitute one species of help for the memory: and this species of help may be justly called the prevention of endless search. For when a person endeavours to recollect, or call a thing to mind; if he has no previous no-" tion or perception of what he is in quest of, he casts about, and tries every track, as it were without end: but if he has any previous notion, this infinity of search is presently cut short; and the memory is brought to hunt nearer home. But in the three instances abovementioned, there


« AnteriorContinuar »