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their present situation, nor daring to proceed farther.

This motion is found in the hearts and pulses of animals, and must necessarily reside in all bo dies that remain in a doubtful state, between convenience and inconvenience, so as that when stretched or drawn, they try to free themselves, at which time they again suffer a repulsion, and yet are constantly trying.

Let the nineteenth and last motion be that which, though it scarce answers to the name of a motion, is yet clearly of that kind, viz. the motion of indolence, or, as we may otherwise call it, the motion of dreading or resisting of motion.

By this motion it is that the earth stands firm in its own bulk, whilst the extremities thereof move themselves towards the middle, not to an imaginary centre, but to union. By this appetite, likewise, all bodies violently condensed have an aversion to motion, their sole appetite being not to move; and although they should be instigated and incited to motion infinite ways, yet they obstinately preserve their own nature as far as possibly they can. But if they are compelled to move, they still constantly endeavour. to regain rest, and recover their former state, so as, if possible, to move no more. And, in this case indeed, they become agile and swift; and,

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as if impatient of all delay, strive with velocity and rapidity to replace themselves. But we have only a partial image, or imperfect notion, of this appetite, because here with us no tangible bodies are condensed to the utmost, on account of the influence and agency of the celestial bodies upon them; and besides they also have some mixture of spirits.

And thus we have proposed the species, or sim-. ple elements of motions, appetites, and active virtues, which are most universal in nature, and under which much natural knowledge is contained. We deny not that other species may perhaps be added, that these divisions may be better adjusted to the true divisions or ramifications of things, and that they may be contracted in number. But we mean not this of any abstract divisions, as if any one should say, that bodies desired either the conservation, exaltation, propagation, or fruition of their own natures, or that the motion of things tends to the conservation and good, either of the universe, as the motions of resistance and connection, or of the larger universalities, as the motion of the greater congregation, rotation, and indolence, or of particular forms, as in all the rest; for though this were true, yet it would be speculative, and of little use, unless it terminated in matter and struc

ture, according to the true divisions or lines of

nature.

In the mean time they will suffice, and be of good service in examining the predominancies of virtue, and searching out the instances of reluctance, which is the present business. For of the motions here laid down, some are absolutely unconquerable, some are more prevailing than others, so as to bind, check, and dispose those others, some dart themselves further out than others, some again excel others in point of time and velocity, and lastly, some cherish, strengthen, enlarge, and accelerate others.

The motion of resistance is adamantine and invincible, but whether the motion of connection be invincible or no, is a question; for we determine neither for nor against a vacuum, whether interspersed or collective, only conceive it plain, that the reason why a vacuum was introduced, by Leucippus and Democritus, (viz. because without it the same bodies could not possess and fill a greater or lesser space) is ill founded, because matter may wrap and unwrap itself in space, within certain limits, without the interposition of vacuity. Nor has air two thousand times more vacuity than gold, as on that supposition it ought to have. And this appears sufficiently from the extremely powerful virtues of

pneumatical bodies, (which must otherwise float like fine dust in vacuo) and from many other proofs*.

But the other motions govern and obey each other, according to their proportions of strength, quantity, velocity, sphere of activity, and also according to the aids and impediments they meet with. For example, there are armed loadstones that will attract, and suspend, sixty times their own weight of iron, so much does the motion of the lesser congregation prevail over the motion of the larger; but this motion yields if the weight be greater. Leather extends to a certain degree, without breaking, and so far the motion of continuity over-rules the motion of tension; but if the tension be carried further, the leather breaks, and the motion of continuation gives way. Water runs out at a crack of a certain size, in which case, the motion of the greater congregation prevails over the motion of continuity; but if the crack be smaller, the motion of the greater congregation gives way, and that of continuity prevails. If a musquet be charged with sulphur, it will not throw out the ball, in which case, the motion of the greater congregation overcomes the motion of dilata

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

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tion; but when the musquet is charged with gunpowder, the motion of dilatation in the sulphur prevails, by the assistance of the motion of dilatation, and of the motion wherewith nitre flies from flame. And the like is to be understood of the other cases. For the instances of reluctance, which indicate the predominancy of virtues, and the proportions wherein they conquer and yield, are on all sides to be sought out with great diligence.

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So likewise the manner and proportions wherein motions give way, are to be carefully examined, as whether they yield entirely, or rather resist to a degree, but are subdued; for in the bodies among us there is no such thing as true and perfect rest, neither in the wholes, nor in the parts, but only to appearance. And this apparent rest either proceeds from an equilibrium, or an absolute predominancy of motions; by an equilibrium, as in the balance, which rests on both sides, when the weights are equal; by predominancy, as in siphons, or perforated wateringpots, where the water rests, and is kept from falling through, by the prevalency of the motion of connection.

But as we said above, it must be observed, how far these yielding motions resist; for if any person should be forcibly bound hand and foot, or otherwise detained, notwithstanding all the

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